;LEAI
WATER POLLUTION CONTROL RESEARCH SERIES • 11050FKE 12/69
     A STUDY OF FLOW REDUCTION
   AND TREATMENT OF WASTE WATER
          FROM  HOUSEHOLDS

DEPARTMENT OP THE INTERIOR • FEDERAL WATER QUALITY ADMINISTRATION

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             WATER POLLUTION CONTROL RESEARCH SERIES


The Water Pollution Control Research Reports  describe  the results
and progress  in the control and abatement of  pollution of our
Nation's waters.   They provide a central source of  information on
the research,  development,  and demonstration  activities of the
Federal Water  Quality Administration, Department of the Interior,
through in-house  research and grants and contracts  with Federal,
State, and  local  agencies,  research institutions, and  industrial
organizations.

Water Pollution Control Research Reports will be distributed to
requesters  as  supplies permit.   Requests should be  sent to the
Planning and Resources Office,  Office of Research and  Development,
Federal Water  Quality Administration, Department of the Interior,
Washington, D.  C.   20242.

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   A STUDY OF FLOW REDUCTION AND TREATMENT
         OF WASTE WATER FROM HOUSEHOLDS
                      by
               James R. Bailey
               Richard J. Benoit
               John L. Dodson
               James M. Robb
               Harold Wallman
  General Dynamics, Electric  Boat Division
           Groton, Connecticut 06340
                    for the

    FEDERAL WATER QUALITY ADMINISTRATION

         DEPARTMENT OF THE  INTERIOR
              Program #11050 FKE
              Contract #14-12-428
     FWQA Project Officer, C. L.  Swanson
Advanced Waste Treatment Research Laboratory
               Cincinnati, Ohio
                December, 1969
  For sale by the Superintendent of Documents, U.S. Government Printing Office
             Washington, D.C. 20402 - Price $1.25

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              FWQA Review Notice


This report has been reviewed by the Federal
Water Quality Administration and approved
for publication.  Approval does not signify
that the contents necessarily reflect the
views and policies of the Federal Water
Quality Administration, nor does mention of
trade names or commercial products constitute
endorsement or recommendation for use.

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                                   ABSTRACT
This study was conducted to find practical means of waste flow reduction or waste
treatment for the ordinary household.  First, the present water quality and quantity
requirements were reviewed to determine the areas where better water and waste
management would be most beneficial.  Much helpful material was gathered from a
review of previous studies on the problems of individual household waste treatment.
More recent information was obtained from manufacturers of plumbing devices and
waste  treatment equipment who were surveyed for available water-saving plumbing
devices and individual waste treatment units. Also, the literature on advanced
water  and waste treatment was reviewed for processes that might be applicable for
individual home usage.

The information collected was then analyzed to determine the most practical methods
for decreasing the waste volume flow from individual households. Homeowners,
plumbers,  architect-engineers,  and equipment manufacturers were  surveyed to
obtain representative opinions from the people who would control the use of any flow
reduction or treatment schemes.  The results of the study and the consumer survey
show that the water used in household functions such as bathing and toilet flushing
can be substantially reduced by the use of more efficient appliances  and plumbing
devices.  The use of most advanced waste treatment techniques and  the reuse of
waste waters is not considered practical except for cases of unusual problems and
extremely high water or waste disposal costs.

This report was submitted in  fulfillment of Program #11050 FKE, Contract
#14-12-428,  between the  Federal Water Quality Administration and General
Dynamics,  Electric Boat  Division.
                                         ii

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                            TABLE OF CONTENTS

Section                          Title                                    gage

  I             INTRODUCTION                                          l

                    Background                                          •*•
                    Present Study                                        2

 H             PRESENT WATER SYSTEM REQUIREMENTS               4

                    Water Quantity Requirements                          4

                    Water Quality Requirements                           8

                        Quality Standards for Household Uses
                            Bathing Water Standards                      11
                            General Washing and Cleaning                 14
                            Lawn and Garden Irrigation                    17
                            Toilet Flushing                              18

                        Effluent Quality Requirements for Disposal          20
                            Effluent Quality for Release to Ground          22
                              Water
                            Effluent Quality Criteria for Release           24
                              to Surface Waters and Storm Sewers

 HI             THE WASTE DISPOSAL PROBLEM OF HOMES NOT         29
                CONNECTED TO CENTRAL SEWERAGE SYSTEMS

                    Background of the Septic Tank Problem                 29

                    Review of Previous Studies                            31
                        Septic Tank Soil Absorption System Research        31
                        Other Individual Systems                          36

                    Equipment Currently Marketed for Treatment of         40
                    Waste from Individual Homes
                        Anaerobic Systems Now Marketed                  40
                            Conventional Septic Tank
                            A Variation of the Anaerobic System           42
                            Discussion of Anaerobic Systems               43

                        Survey of Aerobic Systems                         44
                            Pretreatment                                46
                            Aeration Chamber                            46
                            Solids Separation                             46
                            Final Treatments                             46
                            Economics of Aerobic Treatment Systems       47
                            Discussion of the Aerobic Treatment Systems   48

                                       iii

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                         TABLE OF CONTENTS (Cont'd)

Section                               Title

                    Discussion of the Future Demand for Individual
                    Waste Disposal Systems
                         Present Status of Individual Home Systems         49
                         Future  Projections for Individual Home Systems     49

 IV             HOUSEHOLD PLUMBING FIXTURES TO REDUCE WATER   52
                USAGE REQUIREMENTS
                    Review of Previous  Studies                           52

                    Survey of Plumbing  Manufacturers                    54
                         Faucet  Flow Reduction Devices                   54
                        Water Closets                                  55
                         Urinals                                        57
                        Automatic Clothes Washers                      57
                        Automatic Dishwashers                          59
                         Garbage Disposals                              59
                    Cost Estimates                                     59

                    Water Savings                                      61

                    Cost Evaluation of Plumbing Devices                  61

 V              POSSIBLE TECHNIQUES FOR IMPROVEMENT OF          66
                HOUSEHOLD WASTE TREATMENT

                    Change of Phase Processes                           67
                         Liquid to Vapor Phase Changes                   67
                         Liquid to Solid Phase Changes                    69
                        Solid to Vapor Phase Changes                     70

                    Membrane Processes                               70
                        Reverse Osmosis                               71
                        Electrodialysis                                  71

                    Electrolytic Processes                              72

                    Miscellaneous Processes                            73
                        Oxidation                                       73
                        Chemical-Mechanical Removal of Contaminants     75
                        Collection and Storage                           76
                        Solvent  Extraction                               76
                        Solid Hydrate Formation                         76
                        Maceration-Disinfection                          77
                                        iv

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                        TABLE OF CONTENTS (Cont'd)
Section
  VI
 vn
vni
APPENDIX
Table A-I
Table A-H
Table A-m
Table A-IV
                     Title
ENGINEERING STUDY AND EVALUATION OF PROCESSES
FOR WATER CONSERVATION AND WASTE TREATMENT
    Preliminary Economic Analysis
78
                                                                      84
                   Additional Analysis of Proposed Systems               87
                       Criteria for a Semi-Quantitative System Evaluation  87
                       Evaluation Examples                             90
SURVEY RESULTS
    Water Saving Faucets and Showerheads
    Direct Flush Toilet Valves
    Toilets with Separate Flush Cycles for Urine
    and Feces
    Home Urinals
    Recycle Toilets
    Reuse of Waste Wash Waters
    Individual Treatment Systems
CONCLUSIONS AND RECOMMENDATIONS
    Conclusions
    Discussion and General Recommendations
    REFERENCES
    ADDITIONAL REFERENCES

Waste Treatment Manufacturers
Plumbing Equipment Manufacturers
Cost Data for Liljendahl Vacuum System
Preliminary Cost Comparisons of Alternative Water
and Waste Management Systems
108
108
110
110

110
111
111
111
112
112
115
118
127

131
132
133
135
Table A-V
Questionnaire Distribution
143

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Section

Table A-VI

Table A-VH

Table A-VIH

Table A-IX
         TABLE OF CONTENTS (Cont'd)

                   Title

Results of the Survey of Homeowners

Results of the Survey of Plumbers

Results of the Survey of Architects and Engineers

Results of the Survey of Plumbing Equipment Manu-
facturers
144

146

149

152
                                      vi

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                                  SUMMARY
PRESENT WATER SYSTEM REQUIREMENTS
The literature on household water quantity requirements was reviewed and an average
household water use pattern postulated.  The amount of water used in the various
household functions (bathing, cleaning, toilet flushing, etc.) is estimated.  The water
quantity estimates and the costs associated with using these water quantities are
used as the basis for comparison in the evaluation of all the water-saving or waste
treatment devices.

The various household water uses are then discussed  in relation to the quality of the
water required in each use.  The quality required is considered from three main points
of view:  health, aesthetics,  and engineering suitability. Water quality standards are
suggested for bathing, for general laundering and cleaning,  toilet flushing, and for
disposal  to underground drainage and to surface waters. All uses,  except toilet
flushing, require a relatively high level of quality to satisfy the health, aesthetic,
and engineering criteria.  The  generally high quality  requirements tend to discourage
systems  with multiple water quality levels.   Also, increasing water demands and
water reuse will eventually necessitate very strict disposal requirements.

THE WASTE DISPOSAL PROBLEM OF HOMES NOT CONNECTED TO CENTRAL
SEWERAGE  SYSTEMS
The history of the septic tank problem in the United States is briefly outlined and a
review of previous studies on rural and suburban waste disposal problems is
presented.   Currently available individual waste disposal systems are surveyed
and evaluated with regard to the information obtained from the review of previous
studies.  For most individual waste treatment applications, the anaerobic digestion,
soil absorption type system seems most practical. Waste disposal systems that
discharge effluent to surface drainage  are not considered advisable unless fool-
proof safeguards are  provided to ensure the effluent quality. Statistics show that
individual waste disposal systems are  being installed at a decreasing rate.  The
knowledge gained in the many studies on rural and suburban waste disposal systems
and the development of alternative community waste systems have decreased the
tendency to rely solely on individual waste disposal.  Also, there appears to be a
trend away from individual housing and toward apartment-type living units.  However,
the actual number of individual waste disposal  systems being installed and the
number of these systems already in use are very large. These large numbers,
and the rising water quality standards  demand better  individual waste treatment;
continued study of individual waste treatment systems is essential.
                                       vii

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HOUSEHOLD PLUMBING FIXTURES TO REDUCE WATER USAGE REQUIREMENTS
Previous studies concerning the use of water in plumbing devices and home appliances
were reviewed, and plumbing equipment manufacturers were surveyed to determine
availability of water saving plumbing equipment. Manufacturers, both in this country
and abroad,  have developed water saving faucets, showers, and toilets.   Because of
water shortages and higher water costs, some foreign countries have placed great
emphasis on conserving water.  For example,  a vacuum flush toilet has been developed
in Sweden, and in the United Kingdom toilets with two flushing cycles and water-
saving spray faucets are being used.  The feasibility of using the various water-
saving devices in the household is evaluated on the basis of cost and water savings.

POSSIBLE TECHNIQUES FOR IMPROVEMENT OF HOUSEHOLD WASTE TREATMENT
The demands for high quality water and the increasing costs of securing and treating
water supplies have stimulated the search for better methods of water and waste
treatment.  The literature on advanced treatment methods  was surveyed and the
various methods are discussed as to their applicability for household use.  Most
of the methods considered do not at this time appear suitable for use in individual
households.  However, changes in economic factors and technical improvements
could make some methods attractive for future use.

ENGINEERING STUDY AND EVALUATION OF PROCESSES FOR WATER CONSERVA-
TION AND WASTE  TREATMENT
The practicality of  using the various schemes of waste treatment or flow reduction
in the household are evaluated.  An order-of-magnitude cost analysis of the various
systems led to the following conclusions:
    1.  Reduction  of water usage appears to be the most economically feasible means
        of reducing waste flow from the home.
    2.  Flow control faucets are of marginal value when replacing workable faucets,
        but are definitely warranted for new homes and for necessary replacements.

    3.  Flow control showers are an inexpensive means of economically saving
        considerable quantities of water.
    4.  The use of pressure flush valves  to reduce water flow does not appear as
        advantageous as the redesign of the toilet bowl to allow adequate flushing
        with less water. The pressure flush valve could be advantageously used
        with the redesigned toilet bowl. Siphons,  as used in the English water
        closets, would also provide better volume control than the system presently
        used in the United States.
    5.  The vacuum flush toilet for the individual home is too expensive because
        of the high cost of the accompanying equipment.
                                      viii

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    6.   The major economic disadvantage of the recycle toilets is the high cost of
        the chemical used for disinfecting the recycled flush water.  Development
        of a suitable, lower cost disinfectant could make their use much more
        practical.  There could be a problem with acceptance of reused flush water
        in the home, but this objection does not appear insurmountable.
    7.   Incinerator toilets are excessively costly to operate and maintain  for
        family use.  For certain applications,  such as weekend cabins which are
        used sporadically, the incinerator may be the most economical system,
        but for normal continuous use, the incinerator toilet cannot economically
        compete with conventional systems.
    8.   The analysis of the system to reuse wash waters for toilet flushing reveals
        several very significant facts.  The treatment and the quality standards
        required for flushing water are minimal and the costs are thus relatively low
        in comparison to those for any other reuse.  Yet this treatment and reuse
        is economical in only fair and poor soil areas.
    9.   The additional treatment of the non-sanitary waste waters by distillation,
        reverse osmosis, or a multifilter system for use as laundry and bathing
        water as well as toilet flushing does  not appear economically feasible.
   10.   The treatment of all waste waters by distillation, and  reuse for all purposes
        except drinking is also economically unattractive.

   11.   Aerobic treatment is competitive with  anaerobic systems in poor  soil areas.
        In such poor soil areas some reuse may also be warranted.
   12.   Electrolytic treatment for disposal is not economical for most areas because
        of the low conductivity of the water.
Based on these observations,  the systems that warrant further consideration are
the various means of restricting water usage, reuse  of wash waters for toilet flushing,
and the use of aerobic treatment systems in poor soil areas with the possibility of
treating and reusing portions of the aerobic effluent.

Criteria suitable for a more detailed evaluation were chosen and discussed.  Examples,
using these evaluation criteria with several of the water saving and waste treatment
systems, are also presented.

SURVEY RESULTS
A postal survey of homeowners,  architect-engineers, plumbers, and plumbing
equipment manufacturers was conducted to obtain representative reactions from the
people who would control the actual use of any schemes for reducing water usage or
improving waste treatment and to ensure that the opinions formed from the literature
survey were not contrary to popular practice  or beliefs.
                                        ix

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The response to the survey was relatively good as 387 homeowners, 40 plumbers,
29 architect-engineers, and 8 plumbing equipment manufacturers, representing 50%
of the equipment manufacturers contacted,  52% of the homeowners, 21% of the
architect-engineers, and 18% of the plumbers, filled out and returned the question-
naires.

The survey indicated that water-saving faucets or shower heads and direct-flush
toilet valves are the most acceptable water-saving devices.

Septic tank,  soil absorption systems are by far the most common household waste
treatment system.  Although 67% of the maintenance schedules reported by the home-
owners were inadequate according to the recommendations of the Public Health
Service "Manual of Septic Tank Practice",  most homeowners were pleased with the
performance of their treatment systems.

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                                INTRODUCTION
BACKGROUND

The practice of water reuse is not new or even recent.  The water supply on the
earth is constant and water reuse dates to the beginning of recorded history.  Dis-
tillation, membrane processes,  and freezing techniques which have occurred naturally
for millions of years are being developed into artificial systems capable of producing
pure, drinkable water from waste waters.  Devices are already available to treat
the waste water on space vehicles so that water can be reused.   In some water-short
areas, water from the ocean is being economically reclaimed through distillation,
and work is rapidly progressing in the development of freezing  techniques and in
membrane  technology.

Unfortunately, these processes are only now approaching practical, usable status
for everyday application, whereas water shortages have plagued cities and industries
for centuries. In areas where water has not been plentiful or not easily obtained
various techniques have been developed to permit reuse of water or to relieve
shortages simply by using less water.  Some Asian peoples combated water shortages
by an almost complete,  though primitive and hygienically dangerous,  reuse of their
meager water supply.  The rainfall occurring in the wet season was collected in
open ponds from which water was carried by hand for household use.  To conserve
the supply,  all cleaning and washing were done in the pond and household wastes
were dumped back into it.

In Chanute,  Kansas, during a critical drought in 1956 and 1957,  effluent from a
biofiltration plant was diluted with available river water and treated for municipal
use.  Sewage provided a considerable portion of the water supply for several months,
but there were no reports of physiological ill effects on the population (17).* Many-
industries which have located in water-short areas, for example, Kaiser Steel at
Fontana, California, have found  that processing techniques could be designed to
reduce the  use of water.  Other companies,  such as Bethlehem Steel near Baltimore,
Maryland,  have solved their own water problems and helped to  alleviate pollution
problems by the treatment and reuse of sewage plant effluent.   Tourist facilities at
the Grand Canyon have reused effluent from their waste treatment plant for toilet
flushing and for lawn irrigation since 1925.  In several coastal  areas  such as Long
Island, New York, and Southern California,  treated waste water is injected into the
groundwater reservoirs to prevent intrusion of salt water as the fresh water table is
lowered by pumping.  At Santee, California,  and in the Golden Gate Park, San
Francisco,  California, extensively treated waste water is being used to irrigate
parks and to supply recreational lakes. In many parts of the world, various schemes

*Numbers in parentheses refer to  the  list of references,  pp.  118-126.

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 for reusing treated waste water industrially are already in use; in South Africa
 and Israel, revise for the domestic water supply is also planned.

 Implementation of advanced treatment processes and water reuse depend on the
 development of better systems for collection of wastes and distribution of the treated
 water.  Cities will have to be more comprehensively planned so that urban sprawl,
 with its disproportionate amount of piping,  pumps, and accessories for proper service,
 will be controlled.  The increasing world population and the fixed supply of water
 and fuel make such planning essential for future growth.  Water conservation and
 the reuse of partially treated water is destined to become increasingly important in.
 the task of supplying adequate water to the growing world population,

 PRESENT STUDY
 This study examines the feasibility of applying the principles of water conservation
 and reuse of partially treated water to the household,  not only to stretch the limited
 water supply, but also to provide a transition into the approaching era of complete
 water reuse with the corresponding high level of water conservation necessitated by
 higher costs of water treatment.

 The various uses of water in the typical home are studied in an attempt to find
 methods of reusing partially treated water and changing present home practices
 which use water needlessly or wastefully.  The amount of water that can be poten-
 tially saved in a single household may be relatively small, but even small decreases
 in the daily per capita water use and waste discharge can result in large cumulative
 decreases in costs at the municipal water and sewage treatment plants.  Besides
 savings in operating costs for water and sewage treatment, the decreased usage
 would, delay the need for the construction of new waste treatment facilities, for con-
 struction of larger sewer lines and water mains, and for the development of new
 water supply sources which are becoming increasingly scarce and costly.

 This study also examines the special problems of households not connected to
 central sewerage systems which must depend on individual treatment  units for the
 disposal of their wastes.  Owners of individual treatment units are faced with the
 need for better treatment of wastes to prevent pollution of recreational waters, and
 to protect their own or their neighbor's individual water supply. Economical re-
 duction of waste discharges would facilitate treatment, decrease pollution, and ease
 the demands on an often limited water supply for home owners in areas without
 municipal water or sewerage.

 This study is divided into six major tasks designed to analyze the need for water
 conservation and reuse  schemes and to survey and evaluate available  techniques of
meeting these needs. These six tasks are  listed below:
    1.  Conduct a study and engineering evaluation of possible changes in household
        plumbing fixtures  to reduce water usage requirements, and hence reduce
        the flow of waste water from households.  (Section IV)

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2.   Conduct a study of the magnitude of the waste disposal problem from homes
    not connected to central sewage systems.  (Section III)

3.   Study and evaluate effluent quality criteria (standards) for individual home
    treatment systems.  (Section n)
4.   Survey and evaluate equipment currently ma rketed for individual home
    treatment systems.  (Section ID}
5.   Conduct a comprehensive study and evaluation of treatment processes that
    indicate promise for individual home applications. (Sections V,  VI)

6.   Select the most promising treatment systems for  individual home applica-
    tion.  (Section VIE)

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                                       n

                   PRESENT WATER SYSTEM REQUIREMENTS


Water's most essential function is sustaining life, but this country fortunately has
such bountiful water supplies that the greatest water use in our modern households
is for removing wastes.  We rinse away food wastes from our dishes, the soil from
our homes,  our cars, our clothes, and our bodies.  We use additional gallons of
water to flush away sanitary wastes.

As the population increases and our water supplies become more critical, it may be
prudent to decrease the amount of water used in essential tasks.  This probable need
for changes necessitates an examination of the different household water  uses  and the
problems associated with changing any of the common practices or the appliances
associated with the present water uses. This section discusses household water
requirements with regard to both quantity and quality.

WATER QUANTITY REQUIREMENTS

Because of the importance of water quantities in the planning of water and waste
treatment facilities, the literature contains many design estimates for the daily
per capita water use.  These estimates are usually presented as the quantities needed
for treatment plant design and include leakage into and out of pipes as well as  miscell-
aneous non-household uses.   Relatively few reports have been published on actual
water usage in individual households and the distribution of the water among the
various uses. One report (reference 65A) from the National Swedish Institute for
Building Research arrived too late to be fully evaluated and  included in this study,
but excerpts from several of the tables are included for general information.  This
report appears to contain a wealth of information on the quality and quantity of house-
hold waste waters, however the differences between United States and Swedish water
use must be determined before the data can be used directly.  Available  reports show
that per capita water use varies  widely with the standard of living, the climate,
personal habits,  and the number of persons per dwelling unit.  The actual amount of
water (not including lawn sprinkling) varies from less than 20 to more than 100 gallons
per capita per day (gpcd).  The figures most widely reported are between 40 and  80
gpcd.   In a study of 18 homes (97) the average daily water use per person varied  from
20 to 70 gallons and averaged 44 gallons.   Public  Health Service studies  to develop
design criteria for soil absorption systems, revealed that the average daily water use
was 56 gallons per person.  The  Public Health Service study also cited the results
of an extensive water use study in Bethlehem, Pennsylvania which showed the average
use to be 48 gpcd (86). A study at Johns Hopkins University also indicated an average
per person use of 56 gpd (49). Both the study at Johns Hopkins and the study by the
Public Health Service indicated that gpcd water use was inversely proportional to the

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number of persons per dwelling unit.  The Public Health Service found that the
statistical average water use (not including lawn sprinkling) fit the formula Q =
88 + 26 P, where Q is the daily gallons of water used per household and P is the
number of persons per household.
The water delivered to the households is divided among the various uses in a
different manner in every household.  A few of the published estimates of water use
quantities are listed below.
Household Water Uses (39)
Type of Use
Toilet flush
Bathing
Kitchen
Drinking
Laundry
Cleaning
Sprinkling
Auto washing
Miscellaneous
Estimated Potable Water Use (39)
Type of Use

Drinking,  Cooking
Dishwashing
Garbage disposal unit
Laundering, cleaning
Bathing
                      Total
Percentage
  45
  30
   6
   5
   4
   3
   3
   1
   3
Quantity Used (gpcd)

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 Estimated Distribution of Sewage (90)
Waste
Tot. flow,  (gal.)
Kitchen wastes
Toilet wastes
Showers, wash basins, etc.
Laundry wastes
Toilet Flushing (Family of Four) (14)

Day of Week
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
       Volume of Waste,  gpcd
       30  40  50  75  100
        0   7  10  10   15
       15  15  20  25   30
       15  18  20  25   35
        0   0   0  15   20
       Water used for toilet flushing
       % of total daily intake	
               44.7
               66.9
               47.0
               61.5
               61.9
               68.5
               74.4
G. W.  Reid (73) published the following estimate for the use of water in the home
of an average family of the future consisting of four members  in a house with two
bathrooms, a garbage disposal, a dishwasher and an automatic washer:
         Kem
Drinking and Kitchen
Dishwasher
Toilet
Bathing
Laundering
Autowashing
Lawn watering
Garbage disposal unit
                    Total
All uses except toilet and lawn
watering
Daily Family Use,  gal.
         8
        15
        96
        80
        34
        10
        100
         3
        346
        150
         6
Daily per Capita Use, gal.
        2.0
        3.75
       24.0
       20.0
        8.5
        2.5
       25.0
        0.75
       86.5
       37.5

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Waste Water Flows

    Source                            gpcd

Kitchen                               13.5

Showers and lavatory                   16.4

Laundry                                2.3

Toilets                                 7.     (vacuum toilet 5 flushes)

For the purposes of a standard basis throughout this report, the above data and judg-
ment factors were used to fabricate a "model" home with an "average" family which
uses and disposes of water in the "average" way.  The home and the values used for
water consumption are believed to be typical of a normal family; however, even if
the values used are not exceedingly close to reality, they will serve as a standard
of comparison to which all schemes for waste treatment or reduction of waste flow
can be compared.

The "average" home used as a standard is a three bedroom structure with 1-1/2
bathrooms,  having a shower and tub or a shower-tub combination, and a basement
or storage room where additional equipment could be installed if necessary.  The
home has an automatic washing machine and probably a dishwasher and garbage
disposal unit. The "average" family occupying this "average" house will consist
of two adults and two children who will use water in the "average" way.

The use patterns in this "average"  home were assumed to be in accordance with
the studies by the Public Health Service and Johns Hopkins University which in-
dicated certain household water using functions are relatively independent of the
number of household occupants.  Examples of such functions are laundering,  dish-
washing,  and cleaning.  The amount of water used for cleaning walls, floors, and
fixtures depends primarily on the size of the surface cleaned. Whether done  by hand
or by automatic  dishwasher, the amount of water used for dishwashing is more
directly related to the number of times dishes are washed than to the amount  of dishes
washed.  A similar situation occurs with the laundry.  White goods, colored goods,
and special materials all have to be laundered separately. For small families  this
often means doing a load of washing for a few articles in the amount of water  that
would normally be used for a larger load.

In the "model" home,  the water for these household uses has been set at 55 gallons
per day:  15 gpd for dishwashing, 35 gpd for laundry, and 5 gpd for miscellaneous
cleaning.  The water required for personal uses is set at 50 gallons per day per
person:  3 for drinking and cooking, 20 for bathing, 2 for oral hygiene,  and 25 for
toilet flushing.   Most of the household water and probably at least 75% of the bathing
water will be heated.

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 For the purposes of comparison the following assumptions were made:  (1) $0.42
 per thousand gallons, (2) an additional cost of $0.67 per thousand gallons of water
 heated, and (3) a waste water disposal cost of $0.44 per thousand gallons (municipal
 sewerage).  The schematic diagram of the "model" home with the corresponding
 "average" water uses is shown in Figure 1.

 WATER QUALITY REQUIREMENTS
 Introduction
 This section discusses water criteria and standards: (1) for various household
 applications and (2) for disposal to underground drainage or to surface waters.

 To significantly reduce total household wastewater flow without relinquishing the
 conveniences of modern plumbing and appliances, wastewater treatment and reuse
 systems must be considered.  However,  before treatment requirements for reuse
 can be determined, standards of water quality needed for the various household uses
 must be established.  Although optimum limits of water quality could be established
 for each use in a household, simplicity in plumbing and treatment equipment together
 with the fact that water from any supply point in a household is used for many things,
 dictates that the number of classes of water qualify and the corresponding separate
 piping systems involved be kept to a minimum.

 A new household wastewater system could result in the discharge of a smaller
 volume, but a much more concentrated final effluent.  For that reason, standards
 of effluents for final disposal are also discussed.

 Water quality must be considered from three main points of view:  health,  aesthetics,
 and engineering suitability.  Table I lists some general aspects to consider in each
 category.  In household water systems health is of prime importance.  However,
 health hazards may be eliminated in many cases merely by disinfection.

 It has been said that public policy should never compromise on public health issues,
 and that the proper philosophy for public water supply planning should not be to
 take any available water source and by treatment make it safe for human use, but
 rather to take the best supply available and by treatment make it better.  Un-
 fortunately, the demands of modern life in an industrialized nation seldom permit
 so simple and categorical an approach.   For example, it is economically and
 technically impractical to achieve sterility in public water supplies and human
 foodstuffs, but experience has shown that the arbitrary standards of sanitation now
employed reduce public health risks to a minimal level.

Actual health risks are not the only factor,  however.  Personal habits and current
 social customs may affect water conservation and reuse schemes at least as much
as the technical limits required for health considerations and engineering feasibility.
 For example,  water must have an acceptable appearance and odor even for such low-
 level tasks as washing floors.

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255
Potable
 Water
        Kitchen
        27 gpd
Utility
 Sink
 5 gpd
Laundry

35 gpd
Bathing
80 gpd
Lavatory
  8 gpd
Toilet
100 gpd
      F
   255 gpd
   to Waste Disposal
           dishwashing         15  gpd
           .drinking,  cooking  12  gpd
        Figure 1.  Average Household Water Requirements for a Family
                  of 2 Adults and 2 Children

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                        Table L  Aspects of Water Quality
1.  Health
2.  Aesthetic
3.  Engineering
Chemical quality
Microbiological quality
Taste
Odor
Appearance (color and turbidity)
Temperature
Chemical Qualities (staining)
Corrosiveness
Hardness
Salinity - Metallic Deposits

Abrasiveness
Settleable Solids
Colloid content
Temperature Requirements
Volume Requirements
                                                                 Chemical
                                                                  Content
                                                                 Turbidity
                                        10

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Specific quality requirements for various uses are discussed on suosequent pages.
The following figures and tables show the spectrum of household water uses that
helped dictate the quality requirements specified.  Figure 2 shows a schematic of a
typical plumbing system and  table II shows the water uses at the various supply points.

Quality Standards for Household Uses

The U. S. Public Health Service has developed water quality standards designed to
insure a product satisfactory for all the uses that commonly occur in the household,
including drinking,  cooking,  cleaning,  home gardening, and use in heating systems
(71).  This report uses these water quality standards as the basis of the quality
standards for particular household uses.  For all purposes related to drinking and
cooking,  these standards must be rigidly maintained; in this study it is assumed that
all drinking and cooking needs will be provided from an acceptable drinking water
supply. For most other purposes, certain of these contaminant limits can be relaxed
without increasing health hazards or decreasing the  suitability of the water for the
particular purpose.  In all cases, however, the bacterial limits will be maintained
to guard against disease and  infection; therefore, only chemical and physical standards
will be discussed in the following sections.

Bathing Water Standards
Substances injurious to the skin should not be allowed to accumulate in water reused
for bathing.  For this reason, a pH range is  specified for bathing waters.  The
range of 6.5 to 8.3 was recommended by the National Technical Advisory Committee
(NTAC) Report (95) for bathing water standards  in order to  prevent eye irritations.
The physical limits on color  and  odor should be  maintained for aesthetic suitability.
Turbidity limits may be relaxed slightly.   Limits on the organic contaminants
detected by the carbon chloroform extract should be adhered to in order to prevent
odor and possible health problems.  The chemical limits on cyanide and the heavy
metals listed in section 5.22 of the drinking water standards should be maintained
because of body contact and the possibility of ingestion, especially by small children.
Limits recommended for total dissolved solids in bathing water of 1500 mg/1 are
three times the drinking water standards, but well within the range of useful,
naturally occurring waters.  Hardness limits of 100 mg/1, twice the drinking water
standard,  are considered reasonable for this use.

Limits on some of the other chemicals can also be somewhat relaxed. The ABS
concentration for drinking water is limited to 0.5 mg/1 to prevent frothing problems,
but frothing is less  objectionable in bathing water than in the drinking supply.
Frothing is still very light in concentrations up to 1 mg/1 and this limit is recom-
mended.  For drinking, chlorides and  sulfates are each limited to 250 mg/1.  The
chlorides are limited to prevent a salty taste and the sulfates to prevent a cathartic
reaction in consumers.   Since the water is not to be consumed, the limit of either can
be set higher for actual bathing purposes.  The requirements of the hot water heating
                                        11

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 Potable Water Supply
  Kitchen
  Laundry
                         Sink*
                     Garbage grinder

                     Dishwasher ——
                     Washing Machine*

                     Set Tub*   	
Bathroom
                         Sink*

                         Tub*
                         Shower*.
                         Toilet bowl
                         House heating system

                         Outdoor faucets
                         Floor and other drains
A

*
                          sewer  system  or  septic  tank,,
                          absorption  field  system

Separate Dry Well  ("orbidden by many local codes)

Part of water via  hot water heater.
           Figure 2. Home Water and Waste Flow Pattern
                             12

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              Table n. Home Water Uses At Various Supply Points

Kitchen
    Sink
        Drinking
        Cooking
        Washing - food and equipment
        Bathing
        Household cleaning
        Garbage grinding
        Dishwashing ~ automatic or hand
Laundry
    Automatic, Semi-Auto, or Hand
Bathroom (s)
    Sink
        Drinking
        Bathing, toothbrushing
        Household cleaning
    Toilet - sanitary transport
    Shower - Bathing
    Bathtub - Bathing
        Household cleaning
        Occasional Drinking
Heating System^
    Hot Water Supply
    House Heating System (Steam or Hot Water)
Outside Faucet(s)
    Lawn and Garden Watering
    Car Washing
    Pet Washing
    Sprinkling Children
    Supply to Wading and  Swimming Pools
    Miscellaneous Cleaning
    Occasional Drinking
                                       13

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 and piping system,  however, limit the combined level to 1500 mg/1.  Fluoride
 levels could be increased to 3 times the values established for drinking.  Copper
 and zinc limits can be doubled with no problem other than a bitter taste which would
 probably serve a useful purpose by discouraging drinking.  Iron levels can also be
 raised above the 0.3 mg/1 level recommended to prevent taste.  It has been re-
 commended that a combined iron and manganese level of 1.0  mg/1 would be sufficient
 to prevent staining  in laundry applications (54).  Maintaining  a 0.05 mg/1 limit for
 manganese avoids stains and bacterial growth. Nitrate levels as high as 90 mg/1
 should be permissible.  The limit of 45 mg/1  (as NO ) was set to prevent meth-
 emoglobinemia in infants fed on formula made with high nitrate waters, but surely
 no infant young enough to be affected by the high nitrate levels would be given the
 opportunity to drink even a small amount of bath water, let alone the large quantities
 required for toxic effects.  Significant concentrations of phenols are unlikely to
 appear in household drainage systems, but concentrations in  the bathing water of
 several times the drinking water limits would cause no problems.  The suggested
 standards for bathing purposes are shown in table in.

 General Washing and Cleaning - For general household cleaning and laundering,
 standards can be further relaxed.  The physical standards should still be maintained to
 make the water aesthetically acceptable to the housewife. Limits on the  solids
 concentrations also must be maintained because of the requirements for heating the
 water and the fact that water with high dissolved solids will leave deposits on evapora-
 tion.  The chemical concentration of the other substances can be substantially in-
 creased for household cleaning and laundry without increasing the concentrations
 above the levels normally found in the water to which cleaning and laundering
 solutions have been added.

 Some of the substances will of course linger,  on cleaned clothes,  for example; but
 any increase in concentration level will be unnoticeable and non-toxic to children
 who occasionally chew on their clothes.  Chromium levels of 1.5 mg/1 are re-
 commended as permissible for washing and cleaning.  Little  physiological danger
 exists even from quite high chromium levels  (54).  The taste and odor threshold
 level of chromium are 1.4 mg/1, and the possibility of minor coloration  or taste
 is not deemed unacceptable for this use.  Phenol  levels of 0.01 mg/1 are 10 times
 the USPHS (71) drinking water standards.  High taste levels make ingestion of
 dangerous quantities of phenols unlikely.  Odor thresholds of phenol in chlorinated
 water have been reported to range from 0. 00001 mg/1 to 0.20 mg/1.  The level of
 0.01 mg/1 phenol is a reasonable compromise between chance of unpleasant odor and
treatment requirements.  Although a pH of 6.0-6.8 is recommended for laundry pur-
poses, (54), attempting to achieve such an ideal is unrealistic for home use; the
wider range of 6. 0 to 8.3 will be acceptable for home laundries.  The suggested
quality criteria are listed in table IV.
                                        14

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                 Table HI.  Suggested Bathing Water Standards
Physical Characteristics
    Turbidity
    Color
    Odor
Chemical Characteristics
10 units
15 units
 3 units
    Alkyl Benzene Sulfonate (ABS)
    Arsenic (As)
    Barium (Ba)
    Cadmium (Cd)
    Chloride (Cl)
    Chromium (Cr)
    Copper (Cu
    Carbon Chloroform Extract (CCE)
    Cyanide (CM)
    Fluoride (F)
    Iron (Fe)
    Lead (Pb)
    Manganese  (Mn)
    Iron and Manganese
    Nitrate (NOg)
    Phenols
    Selenium (Se)
    Silver (Ag)
    Sulfates (SO )
    Total Dissolved Solids (TDS)
    Zinc (Zn)
    pH
    Hardness
                    Concentration mg/1
                            1.0
                            0.05
                            1.0
                            0.01
                          500.0
                            0.05-
                            2.0
                            0.2
                            0.2
                            6.0
                            1.0
                            0.05
                             .05
                            1.0
                           90.0
                            0.005
                            0.01
                            0.05
                          500.0
                         1500. 0
                           10.0
                            6.5-8.3
                          100.0
                                      15

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        Table IV. Suggested Standards For General Washing and Cleaning
Physical Characteristics                       Concentration mg/1
    Turbidity          10 units
    Color             15 units
    Odor               3 units
Chemical Characteristics
    Alkyl Benzene Sulfonate (ABS)                       2.0
    Arsenic (As)                                       0.05
    Barium (Ba)                                       1.0
    Cadmium (Cd)                                     0.01
    Chloride (Cl)                                     500. 0
    Chromium (Cr)                                    1.5
    Copper (Cu)                                       2.0
    Carbon Chloroform Extract (CCE)                   0.4
    Cyanide (CM)                                       0.2
    Fluoride (F)                                       6.0
    Iron (Fe)                                          1.0
    Lead (Pb)                                          0.05
    Manganese (Mn)                                     . 05
    Iron and Manganese                                1.0
    Nitrate (NO_)                                    180.0
               O
    Phenols                                           0.01
    Selenium (Se)                                      0.01
    Silver (Ag)                                         0. 05
    Sulfates (SO )                                   500.0
    Total Dissolved Solids (TDS)                      500.0
    Zinc (Zn)                                         10.0
    pH                                                6. 0-8.3
    Hardness                                        100.0
    Alkalinity                                         60.0
                                       16

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Lawn and Garden Irrigation - Standards for irrigation are less exacting than for
household uses.   Untreated sewage has successfully been used for crop irrigation,
and there have been no reports of plant damage by the materials in domestic sewage.
However, the use of untreated sewage on land where human food crops are grown is
not recommended.

There have been reports of typhoid and ascaris worm infection caused by sewage
treated crops, and harmful organisms have been found in vegetables from sewage
irrigated soil.  Since all water should be made biologically safe for accidental
ingestion, this should be no problem.  The tourist facilities at the Grand  Canyon have
used waste water from an activated sludge plant, followed by polishing with anthra-
cite coal filters and chlorination for toilet flushing and lawn watering for  more than
thirty years (36).

The use of an individual household effluent for irrigation purposes, however,  would
require closer supervision to prevent possible plant damage,  since the dilution of
harmful contaminants by the sewage from other homes would not be possible.  Boron,
for example, can cause plant damage in very low concentrations. Tolerance  ranges run
from 0.5 to 1.0 mg/1 for slight to moderate damage for sensitive crops,  1.0 to
2.0 mg/1 for semi-tolerant, and 2.0 to 4.0 mg/1 for tolerant crops.  As borates
are frequently a constituent in household cleaners, it is conceivable that these con-
centrations could be occasionally exceeded in wastewaters.

The effects of various concentrations of surface  active agents in irrigation waters
has not been extensively studied, but, in general, surfactants are not considered
beneficial.  Foams may be produced at low concentrations (0.7 mg/1) and may prove
offensive in a sprinkler system.  Non-biodegradable  detergents could also pollute
ground water if applied to a lawn and garden in sufficient quantities.  Limits are
therefore recommended for surfactant substances for lawn irrigation.

Sulfates in high concentrations are reportedly injurious to plants; 200 mg/1 is
recommended as  a standard for irrigation waters by  McKee and Wolf (54).  They
quote a 576 mg/1 limit as permissible,  and recommend a 500 mg/1 limit for
domestic water supplies.  It is therefore recommended that 500 mg/1 be  allowed as
a limit for lawn irrigation and outside faucet uses.

The limit for copper at the 1.0 mg/1 level of the USPHS standards is retained.
McKee and Wolf recommended 0.1 mg/1 for irrigation, but this is a  secondary use
for water in a household system  and it is not necessary to improve on the basic
water supply for this purpose.

For irrigation a level of 0.5 mg/1 manganese is  permissible.

Chloride must also be limited to a level of 500 mg/1 for lawn irrigation.  A lower
limit would be better, but this level is not infrequent in some areas.   Phenol  levels
of up to 50 mg/1 have been found to be acceptable for irrigation (54).  However,
                                        17

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 at these levels strong odors exist.  Considering the multiple uses of domestic lawn
 irrigation water, a phenol limit of 0.05 mg/1 is recommended.  This level will
 create taste in a chlorinated water,  but the limit is below the danger level, and taste
 will help discourage accidental ingestion.  Other compounds, such as nitrates which
 have fertilizer properties, could be further increased, but the stipulation of water
 not harmful for accidental ingestion suggests limits for these compounds similar to
 the values used for wash waters.  The suggested standards for irrigation are shown
 in table V.

 Toilet Flushing - For toilet flushing, the main requirement of the water  is to carry
 away the wastes.  Water is usually the most convenient and economical liquid to use,
 but under extreme conditions other fluids have served the purpose; for example,
 fuel oil was used to convey wastes in an arctic installation and then burned along
 with the waste for fuel.  Recently,  several attempts have been made to reuse waste
 waters for flushing toilets.  Stored wastewater from laundry and shower has been
 used successfully for toilet flushing with no treatment other than filtration (55).
 Detergents caused no foaming problem and the slight gray color was not found
 objectionable.  As mentioned in the previous section,  treated wastewater is used for
 toilet flushing at the Grand Canyon.  The use of aerobic treatment effluent for toilet
 flushing in individual homes was studied at the Ontario Research Foundation in
 Canada (15).

 Commercial jet aircraft use a recycle system in which recycled waste water (filtered.
 colored, and disinfected) is used for flushing.  The use of a dye colored water for
 this purpose is apparently accepted by the  public.

 Reasonable  criteria for toilet flushing are  minimum odor, minimum staining
 properties and prevention of serious health hazards.  Acceptance of color and
 turbidity is  dependent on public  education.  It is probable that housewives in a
 community with normal city water would be offended by a reuse system.  The reuse
 system reported by McLaughlin (55) was used in the home of the writer,  and there-
 fore the quality of the water was not questioned as it might have been by  an uninvolved
 housewife, nor was the system taxed by introduction of unusual substances through
 the laundry  and shower as it occasionally might be   during normal usage.

 Levels of 1.0  mg/1 ABS have been reported to cause foaming under favorable
 circumstances but concentrations of synthetic detergents were probably higher than
 this in McLaughlin's system and were reported to be no problem.  Of course,
 excessive foaming should be avoided.

 Manganese,  iron, and copper limits may be imposed to prevent staining.  In the
 studies at the  Ontario Research Foundation, this problem was avoided by using a
black toilet bowl which didn't show the stains (12).  However, this  solution may not
be accepted  by the public because of failure to blend with bathroom decor.  The
                                        18

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                 Table V.  Suggested Irrigation Water Standards

Physical Characteristics
    Turbidity          10 units
    Color             15 units
    Odor              3 units
Chemical Characteristics                      Contamination in mg/1
    Alkyl Benzene Sulfonate (ABS)                       1. 0
    Arsenic (As)                                       0.05
    Barium (Ba)                                       1.0
    Cadmium (Cd)                                     0.01
    Chloride (Cl)                                    500.
    Chromium  (Cr)                                    0.05
    Copper (Cu)                                       1.0
    Carbon Chloroform Extract (CCE)                   0.4
    Cyanide (CN)                                      0.2
    Fluoride (F)                                       6.0
    Iron (Fe)                                          1.0
    Lead (Pb)                                          0.05
    Manganese (Mn)                                    0.5
    Iron and Manganese                                1.0
    Nitrate (NO0)                                    180.0
               O
    Phenols                                            . 05
    Selenium (Se)                                      0.01
    Silver  (Ag)                                         0.05
    Sulfates (SO4)                                    500.
    Total Dissolved Solids (TDS)                     1000.
    Zinc (Zn)                                         10.0
    Boron  (Bo)                                         1»°
                                       19

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 necessity of treating flushing water to limit staining may impose economic and
 physical constraints that would limit the scope of any reuse system.  The extent of
 this problem would depend on the degree of reuse, the number of use cycles before
 disposal, and the concentrations of staining agents.

 The desirability of adding disinfectants to the flushing water will depend on the system.
 Disinfection was not considered necessary for McLaughlin's wash water reuse system,
 but the effectiveness of the detergents and bleaches in reducing bacterial populations
 should be investigated.  Bacterial counts for the system reusing aerobic treatment
 effluent were high, but the addition of disinfectants would disrupt the treatment system.
 Therefore in this type of system bacterial kill without a residual effect (heat,  radiation,
 or ozone for example) will be required.

 The sug^sted standards for toilet flush water are given in table VI.

 Effluent  Quality Requirements for Disposal

 Criteria promulgated by the USPHS (90) specify that human and domestic wastes be
 disposed in such a way that:
     1.   They will not contaminate any drinking water supply.
     2.   They will not give rise to a public health hazard by being accessible to
         insects,  rodents,  or other possible carriers which may come into contact
         with food or drinking water.

     3.   They will not give rise to a public health hazard by being accessible to
         children.
     4.   They will not violate laws or regulations governing water pollution or
         sewage disposal.

     5.   They will not pollute or contaminate the waters of any bathing beach,
         shellfish breeding ground, or stream used for public or domestic water
         supply purposes, or for recreational purposes.

     6.   They will not give rise to a nuisance due to odor or unsightly appearance.

There are,  however,  no quantitative standards which household  effluents, as such,
must meet. Normal, generally acceptable disposal methods now include public
sewerage systems and individual under ground disposal systems.  This section
discusses criteria and standards applicable to household effluents for discharge to
ground waters, surface waters, and storm sewers.

Estimates of water used in various household appliances and released to drains
vary widely. Total wastewater volume from three homes studied (97) ranged from
less than 20 to 195 gpd per person.  Since wastewater volume varies so widely, the
concentration of specific pollutants will also vary widely. A list of normally
                                        20

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              Table VI.  Suggested Toilet Flushing Water Standards
A.  Physical Characteristics
    Turbidity                  20 units
    Color                      30 units
    Odor                       6 units

B.  Tentative Limits of Staining Agents
    Mn                        0.5  mg/1
    Cu                        1.0
    Fe                        1.0
    Fe+Mn                   1.0

C.  Disinfection may be Desirable
                                         21

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 occurring potential pollutants found in household drains is given in table VII.  Although
 typical concentrations of these substances are quite low, actual concentration may
 intermittently reach dangerous levels relative to potential reuse with minimal treat-
 ment.  A system ensuring that all wastewater is subject to a minimum dilution must
 be used even when reuse is only for lawn irrigation.

 Effluent Quality for Release to Ground Water - The prime basis for the design of
 individual underground disposal systems is that they should have a long life without
 failure. In practice, failure can be defined simply as refusal of the system to accept
 waste,  resulting in blocking of plumbing facilities  or appearance at the ground surface
 of objectionable fluids.  Although much work has been done on the design, installa-
 tion,  and maintenance of septic tank and seepage bed systems to ensure long life
 without failure,  studies of the state of effluent fluids leaving the immediate seepage
 area are sparse, and their results are inconclusive.  However,  certain standards
 of effluent quality are implicit in the codes for underground disposal systems.

 Primarily,  in the household septic tank system, anaerobic digestion takes place
 in the septic tank, and a clarified fluid effluent is released to aerobic percolative
 filtration through at least four feet* of the soil absorption system.  Accordingly,
 after the anaerobic septic tank environment,  and the aerobic soil percolation coupled
 with mechanical filtration effects, water reaching  the ground water table from a
 household septic tank and absorption field operating as designed  should be pathogen
 free,  and should contain only minimum amounts of organic substances, ammonia,
 etc.   Thus,  the construction requirements for soil absorption systems (particularly
 requirements regarding location with respect to rock ledges and the water table) are
 necessary to protect the ground water supply, as well as to insure good operation.

 Nitrates,  however,- which are the normal end products of aerobically digested
nitrogenous organic matter, are not removed from deep ground waters by plant
 life.  Thus, water percolating from cesspools and  leaching fields can cause dangerous
concentrations of nitrates in individual water supplies.  Nitrates (the cause of meth-
emoglobinemia)  are toxic to infants at concentrations which are harmless to older
children and adults.   Nitrate concentrations up to 40 mg/1 have been found at a
distance of 20 feet from a septic tank disposal field (70). Water containing a combined
nitrate plus nitrite level of 45 mg/1 is considered  unsafe for the preparation of baby
formulas or other bottle feeds.  The septic tank code specifications for distance
between disposal field and water supplies are intended not only to insure adequate
filtration but also to allow for some dilution of wastes not removed.
*This figure (4 feet) is derived from the geometry of absorption fields as
 recommended by the Manual for Septic Tank Practice
                                        22

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                    Table VH.  Potential Household Pollutants
KITCHEN
    Sink
        Dishwashing Debris - detergents, soaps, greases,  food and beverage
        leftovers, any substance deposited on dishes.
        Drain Cleansers
        Oven Cleaners
        Household Chemicals - Bleaches, ammonia, polishes, floor and
        furniture waxes, solvents, ink, insect sprays.
        Body Soil and Wastes - Sputum, vomitus, etc.
        Any liquid or semi-liquid substances found in household.
    Dishwasher - Dishwashing debris.
LAUNDRY
    Detergents, bleaches, soaps.
    Soil from clothing (may include small amounts of any household substance).
BATHROOM
    Sink - All substances listed under kitchen sink except dishwashing debris
        Toothpaste, saliva, naso-pharyngeal mucus
        Body soil - (anything washed from body)
    Tub and Shower - All substances listed under kitchen sink except dishwashing
    debris, body soil, urine, occasionally - vomitus, feces
    Toilet - Sanitary Waste
        Any liquid found in household and solids small enough to be flushed.
                                       23

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 ABS and similar refractory synthetic detergents are extremely persistent in ground
 water.  Their use, however, is decreasing, and biodegradeable substances  are
 taking their place,  reducing the magnitude of this problem.

 In summary, explicit standards for wastewaters released to ground waters by
 individual underground disposal systems cannot be specified; requirements will differ
 in each area.  Even the best septic tank soil absorption systems will allow significant
 concentrations of nitrates to develop in ground water.  However,  well designed
 systems of sufficient capacity in relation to loading will prevent pathogenic bacteria
 and most other contaminants from reaching the ground water table.

 Extensive treatment is usually required to enable the water to enter the ground water
 reservoir.  Deep wells for the injection of renovated municipal waste water are
 planned along the south shore of Long Island.   These will reduce ground water draw-
 down and provide a hydraulic barrier against sea water encroachment.  In that area,
 27 mgpd of treated wastewater will replace the fresh water now lost in outflow toward
 the sea (83, 84). The injected waters will conform to the USPHS drinking water
 standards and to other standards to ensure injectability.  Degassing and removal of
 other constituents which might prevent  continued injection will be practiced.

 For disposal of wastes to the underground,  standards similar to a Pennsylvania
 regulation are recommended.  This regulation prohibits underground disposal except
 in such cases where it can be demonstrated that no conditions prejudicial to the
 public interest will result (54).  This inherently requires that water reaching ground
 water reservoirs must at least meet drinking water standards.

 Effluent Quality Criteria for Release to Surface Waters and Storm Sewers - Water
 pollution in the past few years has engendered public demand for stricter surface
 water standards.  Recommendations of various groups, and legislation resulting from
these recommendations,  are trending toward controls that preserve and enhance the
quality of water resources.   Although there is  some argument for the use of surface
waters for waste transport and treatment,  this aspect of stream employment is
 receiving less favor.

 The Suggested State Water Pollution Control Act, Revised (1965), of the Federal
Water Pollution  Control Administration, has the provision as a statement of policy
 "that no waters be discharged into the waters of the state without first receiving the
necessary treatment or other corrective action ... to provide for the prevention,
abatement and control of new or existing water pollution".

 In some states,  the standards refer to the  effluents before discharge into the
 receiving stream.  In others, the standards refer to the streams after having
received effluents.  In general,  at least secondary treatment of wastes (viz.,
chemical, physical or biological treatment in addition to gravity separation of
solids) is required  in accordance with federal policy.
                                        24

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Storm sewers,  when they discharge into streams, are regulated similarly to other
sources of pollution.  Most legal restrictions are directed toward "sanitary sewage and
industrial wastes".  An International Joint Commission on Boundary Waters Control,
considering U.  S.  Canadian boundary waters, included storm waters in their re-
commendations that effluent waters be treated so as to achieve stated conditions in
the open waters.  When any sewage waters,  even when treated, are discharged into a
storm sewer system, by one line of reasoning the storm sewer becomes a sanitary
sewer, essentially an extension of a sewage treatment plant outfall.  Because of
possible health problems associated with sanitary wastes, such discharges of treated
or untreated sanitary sewage to surface waters or storm drains are usually prohibited
by state or local health authorities, except where constant surveilance is provided
by qualified personnel.

Although storm water run-off from urban, suburban,  and exurban areas can be as
high in BOD as sewage, these waters are not usually as rich in plant nutrients
(phosphate and nitrogenous  species).  Eutrophication of receiving waters,  especially
impoundments, has become a serious problem, and tertiary treatment for nutrient
removal is often required.  Disposal of individual household effluents to surface waters
and storm drainage systems could accelerate the eutrophication of receiving waters.

Non-degradeable polluting substances such as chlorides,  metallic and other dissolved
salts, and many toxic, corrosive,  colored and taste-producing materials are depen-
dent on dilution for maintenance below  acceptable levels.  In some streams, these
substances and others such as pharmaceutical and agricultural chemicals,  pesticides,
and synthetic detergents are likely to increase in concentration downstream as the
water is  reused (33). Broader legislative controls are being recommended in trade
literature and by advisory groups.

The demands for high quality surface waters will significantly affect the disposal of
effluent from individual household  treatment systems. In many states, effluents
discharged to surface drainage are the responsibility of state agencies and individual
systems may be forced to meet the same effluent standards as municipal treatment
plants.  The demand for assurance of high effluent quality and the possibility of
future demands for removal of nutrients from the effluent could make  the surface
disposal of individual treatment system effluents impractical.

An inclusive set of water quality limits for public water supplies was recommended
in the NT AC Report (95).  It is not necessarily suggested that  the effluents should
meet these standards; however,  it is pointed out that multiple  stream water reuse
causes almost any effluent now released to surface water to be eventually a constituent
of a public water supply, and these standards may be eventually  recommended for
waste-water treatment goals.

Anything short of secondary treatment of effluent for discharge to surface waters
will have to be considered marginal, open to probable criticism, and dependent on
special local conditions, if indeed  it will be  permitted at all.  Planning and engineering
must consider the  trend toward tighter control and policies of  water resource  enhance-
ment.
                                        25

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 Conclusions
 A summary of the recommended water quality standards is presented in table VHI.

 Several final remarks seem pertinent to this discussion.  While the concentration
 levels of some contaminants may increase several times as standards are
 successively relaxed for various purposes, the allowable concentrations of some
 substances in each case are still relatively low and continued surveillance is
 required to see that the limits are not exceeded.   The only reuse for which this is
 not extremely important is toilet flushing.  Ultimately engineering considerations
 will determine if these varying levels of water quality can be practically supplied
 to the various supply points,  or whether only two or possibly only one level of water
 quality is feasible for a household.

 For effluent disposal the standards are being raised.  The  areas where discharges
 of less than secondary treatment quality are permitted are decreasing rapidly.  la
 fact, under the influence of the increasing population the trend is toward demands
that only water of drinking quality can be disposed to ground or surface water
 supplies.  It is this trend that will eventually make water reuse  economically
 imperative.
                                        26

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Table VDI.  Summary of Recommended Water Quality Standards
                     (Limits in mg/1)
Turbidity
Color
Odor
ABS
Ag
As
Ba
Bo
Cd
Cl
+ 6
Cr
Cu
CCE
ON
F
Fe
Pb
Mn
Fe + Mn
N03
Phenols
Se
so4
USPHS
Drinking
Water
Standards
(mandatory
limit)
5
15
3
0.5
(0. 05)*
0.01 (0.05)
(1.0)

(0. 01)
250
(0. 05)
1
0.2
0.01 (0.2)
(Appendix IA)
0.3
(0. 05)
0.5

45
0.001
(0. 01)
250
Bathing
Water
10
15
3
1.0
0.05
0.01( .05)
(1.0)

0.01
500
0.05
2.0
0.2
0.2
6.0
1.0
0.05
0.05
1
90
0.005
0.01
500
General
Washing
and
Cleaning
10
15
3
2.0
0.05
0.05
1.0

0.01
500
1.5
2.0
0.4
0.2
6.0
1.0
0.05
0.05
1
180
0.01
0.01
500
Irr.
Waters
10
15
3
1.0
0.05
0.05
1.0
1.0
0.01
500
0.05
1.0
0.4
0.2
6.0
1.0
0.05
0.5
1
180
0.05
0.01
500
Toilet
Flushing
Waters
20
30
6







1.0



1.0

0.5
1.0



                            27

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                             Table VIE.  (Cont'd)




TDS
Zn
Ph
Hardness
Alkalinity
USPHS
Drinking
Water
Standards
(mandatory
limit)
500
5





Bathing
Water
500
10
6.5-8.3
100
60
General
Washing
and
Cleaning
500
10
6. 0-8. 3
100
60


Irr.
Waters
1000
10
6.5-8.3



Toilet
Flushing
Waters





*Numbers in parenthesis are considered the maximum allowable limits
                                      28

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                                     m
               THE WASTE DISPOSAL PROBLEM OF HOMES NOT
               CONNECTED TO CENTRAL SEWERAGE SYSTEMS
INTRODUCTION

This section discusses (1) the background of the septic tank problem (2) a review
of previous studies on waste disposal for homes not connected to central sewerage
systems, (3) a survey of the individual waste disposal systems presently available
and (4) the magnitude of the individual waste disposal problem, including an
estimation of the present  number of homes served by individual waste treatment
systems and a discussion of future trends.

BACKGROUND OF THE SEPTIC TANK PROBLEM
Homes that rely on individual household waste treatment units for waste disposal face
different and more immediate problems than homes connected to a central sewerage
system, since wastes are treated on the homeowner's own lot in  his own system.
Malfunctions of the waste disposal system become a problem in his own home, not
somewhere across town at the sewage plant.  It is the homeowner1 s own yard that has
unpleasant odors, his own plumbing fixtures that won't function,  and his own back-
yard that may be torn up.  The many and varied household waste products are not
diluted and combined with the wastes of hundreds  or thousands of other homes, but go
directly to the homeowner's own disposal unit and directly affect the treatment
efficiency and the useful life of the treatment system. When the  treatment device is
malfunctioning or must be replaced, the homeowner must face the maintenance or
replacement costs himself;  it is not a shared community expense.  In spite of these
problems, it should be pointed out,  that the individual waste disposal system is not
always a source of trouble;  in many cases it is the most practical and economical
solution to the waste disposal  problem.

The problem of waste disposal from homes not connected to sewerage systems has
largely developed since the  late 1930's.  The clear differentiation between urban
and rural society had begun to fade as new technology, new demands, and new jobs
began to take effect.  Until the development of rural electrification,  most rural
homes had lacked not only electrical appliances but also modern  plumbing due to
the absence of a pressurized water supply (100).  Thus,  the rural electrification
program initiated the development of modern rural plumbing and greatly increased
the demand for the septic  tank soil absorption system which had first been patented
by John Louis Mouras and Abbe Moigno in 1881 (102).
                                       29

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 These septic tank systems consisted of a tank in which the raw sewage was allowed
 to anaerobically decompose before being applied to a subsurface soil bed and were
 usually constructed according to local "rules of thumb" or according to construction
 guides supplied by the state or federal health departments.  In the relatively sparsely
 populated rural areas these systems apparently worked satisfactorily as health
 officials  received very few complaints.  However,  the paucity of complaints probably
 resulted  from the relative separation of the systems from populated areas and the
 tendency of the owners to personally repair or replace their own sewage systems with-
 out reporting the trouble to health officials (100).

 Following World War n, the economic and social changes that had begun slowly were
 rapidly accelerated. The years of war had left many  domestic supplies and appliances
 in short supply. This backlog of consumer demand helped to  open jobs for the nearly
 ten million returning servicemen, who further spurred the consumer demand with
 their suddenly increased buying power.   Most of these new jobs were in the cities,
 and the migration from farms to cities that had begun in the 1800's swelled rapidly,
 creating  new housing demands in the central cities.  Because of the higher wages and
the availability of easy credit through the Federal Housing Administration, much of
 this housing demand was for individually financed homes.  The percentage of owner
 occupied homes rose from about 44% in  1940 to more  than 60% in 1960.

 Since most of the building sites within the area served by city sewerage systems
were either occupied or priced out of the speculative home building markets, most of
this housing growth occurred on the  outskirts of the large cities (24).  Also, the enticing
claims that the suburban developments combined all the best features of both city and
country living were partly true.  These  suburbs were close enough for the convenience
 of working,  shopping, and enjoying entertainment centers, and far enough to escape
the smoke, dirt, and noise of the industries.  This trend to locate in the suburbs
 surrounding the central cities was further accelerated by the  superhighway systems
which made commuting from the suburbs to the cities much easier. The super-
 highway construction itself destroyed city housing and created new demands in the
 suburbs (21).  Industries and businesses followed this outward expansion and opened
numerous branch offices and local facilities in the developing areas surrounding the
central cities in an effort to escape the  rising taxes and growing traffic problems.

Water supply for these developing fringe areas was achieved relatively simply through
private wells or extensions of the municipal water system (100).   Sewage disposal
was not as easily supplied,  however. Many of these suburbs  were well beyond the
economic limits of the central sewage disposal system.   Providing city sewerage
service from the central city would have required expensive sewer extensions
with the additional problems of infiltration (7)  and probably would have required
the construction of pumping stations  since many suburbs were located on marginal
lands topographically unsuited for gravity drainage of sewage. Besides,  in most
cities the sewage treatment plants were not prepared to treat the increased volume
of sewage from the subdivisions even if  a collection system were provided (87).
Some state laws also favored  individual  waste  disposal systems.  In Connecticut, for
                                        30

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example, the law forbids private institutions to operate sewage treatment plants as
a public utility.  Thus, systems that may have been more practical for both builder
and buyer were never considered.

There was no immediate public concern,  however, because the septic tank  soil
absorption system seemed to offer an adequate  solution to the problem.   It  could
be easily installed by the builder, expenses could be accurately charged to  the
home buyer, and it seemed to offer city-type waste disposal at a relatively low cost,
and with little or no maintenance.  The soil absorption system was counted on by the
central cities to give adequate treatment to the  septic tank effluent right on the home-
owners lot.  Health officials, though dubious of this wide-spread adoption of a relatively
untested sewage disposal system, had no real basis on which to forbid septic tank use
(100).

REVIEW OF PREVIOUS STUDIES
Unfortunately, the phenomenal increase in the use of septic tank systems after World
War n did not occur  as uneventfully as had been hoped.  As large numbers  of in-
dividual septic tank systems were put in operation near the cities and relatively
close to neighboring homes, failures were readily noticeable.   Due to inadequate
or improperly constructed systems, many of the septic tank soil absorption systems
failed.  In some U.S. communities, up to a third of the septic tank systems in the
subdivisions failed within three to four years after installation, thus creating an un-
expected financial burden for the homeowners and bringing the problem to the atten-
tion of the Federal Housing Administration,  the principal insurer of  housing loans,
and to the attention of the Public Health Service,  the principal agency in  charge of
sanitary and health problems (53).  These organizations  initiated a series of exten-
sive studies to explore the mechanisms of waste water disposal in the soil  and the
reasons for the eventual failure of the septic tank soil absorption systems.  Later
research was designed to investigate other waste treatment systems that might be
better suited for the  fringe areas of the large cities.  The review of these studies has
been divided into two major groups for the convenience of discussion.  These major
headings are:  studies on septic tank and soil absorption  systems and studies on
other individual  treatment systems and alternatives to individual systems.

Septic Tank Soil Absorption System Research
The common concept of a septic tank soil absorption system is a tank in  which
to collect and digest  sewage solids  and a soil absorption  system from which the
effluent percolates into the ground (see figure 3).  The knowledge of the complex
biological,  chemical, and physical  processes that occurred in this type sewage
disposal was  very limited and there was no good basis for the design of septic tank,
soil absorption systems.  The purpose of the initial studies was therefore to
determine the controlling parameters of septic tank,  soil absorption systems for
sewage  disposal.
                                       31

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                             inspection
                                ports
   w
        I//// / A
                        I  /  /  /  /1
inlet
^
             •:-%;.' *
floating scum
                         liquid
                                     LV
                                        -^
                           sludge."..  "" V>:    /s-.^v
                Figure 3. Topical Septic Tank Design
                               32

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The treatment efficiency of the most commonly used septic tank designs was found
not to vary significantly as long as the volumes were comparable.  Volume was
found to be the single most important factor of the design of the septic tank.  The
volume is very important in allowing adequate settling time, providing capacity for
surge flows as from the bath and laundry, and in providing dilution for possible
chemicals that could upset digestion, Compartmentation further improved perform-
ance by forcing greater utilization of the tank volume (9).  More sophisticated designs
could probably be used to improve settling efficiency, but the need for simple
construction and ease of cleaning has kept designs simple.

Later studies investigated the  addition of chemicals to the septic tank (through the
water closet) in an attempt to achieve more  complete solids removal in the septic
tank (101). Organic and inorganic flocculants were found to achieve significant
solids reductions,  but the actual benefit of the addition is questionable.  In these,
tests run at the University of California, Sanitary Engineering Research Laboratory,
no overall beneficial effects on the soil absorption system were observed  (101).

A major problem connected  with the septic tank is maintenance.  Not all the material
which settles out of the influent sewage is decomposed.  Some of the organic  material
and most of the inorganic materials  are essentially unaffected by the biological activity
in the septic tank.  Therefore, the amount of solid material in the septic tank slowly
increases, and contrary to the popular belief in many areas, no chemical or  biological
additives have proven effective in lessening septic tank maintenance (9,40).  At some
time, the accumulated solids will attain sufficient bulk to prevent the attainment of
the relatively quiescent conditions which are required for the gravity separation of
suspended solids.  Thus, as the volume of accumulated sludge reaches a certain level,
the efficiency of the solids removal decreases markedly and the amount of solids
discharged to the soil absorption system increases.  If this solids discharge  is
allowed to continue,  the system will soon fail.  To safeguard the system, the level
of accumulated sludge and scum (floating solids) must be checked often enough to
allow for the timely removal of the accumulated solids.  Unfortunately, checking
the level of the solids in the septic tank is not easily accomplished.  The earth over
the septic tank must be removed, the top opened,  and some type of measuring device
used to physically measure the sludge and scum levels (90).  It is time consuming,
odorous, and messy hard work which is understandably postponed even by home-
owners who realize that the  septic tank system does require maintenance. Until
trouble erupts, the tendency is to assume that the system is working efficiently.

Probably the most important and expensive, but oddly enough, the most neglected
part of the septic tank,  soil  absorption system is the soil system. It is in the soil
that the remaining nutrients in the septic tank effluent must be oxidized and the
remaining particles and microorganisms filtered out before the used water reaches
the ground water reservoir.  The soil absorption system is the final safeguard of
ground water quality.  B is also the  quantity limiting factor of the system since
water cannot be discharged through the septic tank faster than it can be absorbed
into the soil absorption system.  If the soil  cannot absorb the septic tank effluent

                                        33

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 as fast as it is applied, the excess sewage must either back up into the house waste
 system or erupt to the surface of the ground.  Either case is a serious problem.
 Sewage stopped drains and sanitary fixtures are not only inconvenient and odorous
 but present a possible health hazard (75).  K the sewage breaks through to the ground
 surface,  there is danger of disease germs being spread with surface drainage,
 possibly into drinking water supplies, and collecting in puddles with the likely contact
 of children and animals.  However, unlike the septic tank which is a physical item
 that must be specifically purchased, the soil absorption system appears to simply
 convey the liquid waste to the soil through a gravel filled hole.  Thus,  while builders
 have generally accepted the need for larger capacity septic tanks as water usage
 has increased, they have been reluctant to increase the size of the soil absorption
 field (20).

 The studies sponsored by the  Public Health Service  and the Federal Housing
 Administration have attempted to clarify the mechanisms of treatment in the soil
 absorption system and the mechanisms by which the soil absorption system becomes
 clogged.  The ultimate aim of the studies was to obtain sufficient information to allow
 recommendations for changes in the design, construction,  and operation of soil
 absorption systems so that more efficient,  safer, and longer lasting service would
 be promoted.

 The magnitude of the task undertaken is awesome.  The soil itself varies from gravel,
 through sand and silt,  to clay in size,  and from pure sand to humus in organic content,
 with all manner of variations and combinations between these extremes. The con-
 centration, volume,  chemical nature,  and rate of sewage applied varies with the
 geographical location and from household to household. The weather is a very
 important factor because it influences ground water  level,  rate of evaporation, and
 to some extent the rates of water usage.  To complicate matters,  the amount of
 sewage applied to the soil is two to ten times as great as normal rainfall and
 accepted irrigation rates at which water normally seeps into the soil in nature (9).
 As might be expected under these circumstances, the first attempts to systematically
 design soil absorption systems were successful only in a limited area.  In the 1920's
 Henry Byon had established an empirical formula to correlate the percolation rate of
 pure water to the percolation rate of sewage for some troublesome areas of his
 jurisdiction.   In an attempt to lend some rationality  to the design of their own soil
 absorption systems, other public health officials used Byon's formula or a slightly
 modified version of it for design in their own areas.  The success of these attempts
 was understandably limited.

 Other more general design systems were also suggested.  These attempted to find
 the rate of percolation of water through the soil at equilibrium rather than at initial
 conditions (51).  However, tests run at the  University of California indicate that the
 long-term sewage infiltration  rate is not significantly related to the initial infiltra-
tion rate for fresh water which is measured by any of the standard percolation tests
 (100).
                                       34

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Researchers soon realized the futility of attempting to analyze the disposal param-
eters prevalent in all the different sections of the country and instead attempted to
first define and explain the fundamental mechanisms of disposal in the soil absorption
system.  Studies to determine how  soil clogging began and how  it progressed revealed
many unexpected facts. Between the very porous coarse sands and gravels, which
almost never clogged, and the almost impervious clay soils, which passed no water
at all,  the type of soil seemed to have no great effect on the clogging by septic tank
effluents.

The studies revealed that the  percolation of even pure (but not sterilized) water
through this middle range of soils resulted in the reduction of the infiltration rate
to a relatively low percentage of the initial rate.  It also became clear that the
infiltration rate,  rather than the percolation rate,  is the limiting factor.  Obviously,
the rate at which water can pass through the lower soil is insignificant if it can't get
through the surface layers (101).  The soil surface,  or more accurately, the inter-
face between the waste distribution system and the soil,  is the  key to clogging
problems.  Soil grains are consolidated at the surfaces by the passage of even pure
water, and particles in the septic tank effluents are filtered out and collect at this
interface further reducing infiltration rates.  At times of high flow the reduced  in-
filtration rates cause ponding of the effluent over the soil and promote the anaerobic
conditions which lead to the accumulation of a ferrous sulfide precipitate.  The
colloidal ferrous sulfide particles can pass through the surface mat and  the insoluble
ferrous sulfide collects in the anaerobic conditions deeper in the soil.  This gela-
tinous, black precipitate can  soon form an impervious layer completely blocking
further infiltration.

However, even this  accumulation would not necessarily ruin the system. Further
research showed that the ferrous sulfide soil blockage was reversible.  Under
aerobic conditions,  the ferrous sulfide is oxidized to a soluble ferric salt and flushed
through the soil, thus allowing infiltration to continue (100).  The aerobic conditions
also relieve the surface clogging as the organic  solids are oxidized more rapidly.
Aerobic unsaturated soil  is also essential to the removal and oxidation of detergents
and other resistant organic compounds (74).  The problem is to obtain and maintain
these aerobic conditions.  The most effective technique for achieving these aerobic
conditions was to merely rest the system and apply no more effluents.   Unfortunately,
the resting period required to restore infiltration effectiveness is much longer  than
now practical,  often several months (68).

Other  investigations showed that many misconceptions and errors had persisted in
the installation and design of  soil absorption systems.  Studies showed that the  distri-
bution boxes, designed to give equal distribution of septic tank effluent to all  parts
of the  soil absorption system, were not only unnecessary and theoretically unsound,
but unworkable in practice. Serial distribution was found to be more efficient and also
much less expensive (22).  In addition, the researchers found that construction prac-
tices often partially destroyed the  infiltration capacity of the soil absorption system
                                         35

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 before it was even put into service.  The use of modern excavating equipment has
 increased the possibility of smearing and sealing the soil surface so that extra care
 must be taken in construction,  and in the scheduling of the construction,  so that wet
 earth conditions conducive to smearing may be avoided (20, 8).

 The summation of the experience and knowledge gained through these studies has
 been embodied  in the 1967 revision of the Public Health Service  Publication No. 526,
 "Manual of Septic Tank Practice".  This manual is well written  and serves as an
 excellent text and reference for health officials and septic tank installers.   It provides
 essential information to guide the choice of the system and the design, construction,
 and maintenance of the system chosen.   It only begins to fulfill the basic need for
 educating the users of septic tank systems, however.  It is too long and too detailed
 to serve the needs of the average homeowner.  More brochures  such as Public Health
 Service Publication No. 73, "Septic  Tank Care" (91), are needed and wider distribu-
 tion,  possibly through septic tank dealers or installers, Health departments, agri-
 cultural extension services, etc. is  needed.  The septic tank installers themselves
 have expressed a need for more information on the proper installation and care of
 septic tank, soil absorption systems (47).

 Another item worth investigating would be the design of septic tanks with unobtrusive
 clean-out and inspection ports on the surface.  This would eliminate most of the work
 in checking the level of floating and settled solids in the tank and promote better
 maintenance.  Septic tank cleaners have reported that in over half the cases in which
 they are called, the owner has acted too late and the soil absorption field has already
 been clogged (9).

 Other Individual Systems
 Even with the best design,  construction, and maintenance, septic tank, soil absorp-
 tion systems cannot be universally employed. In many areas, the soil is not suitable
 for soil absorption type waste disposal.  It has been estimated that less than half
 the land in the United States is suitable for disposal of waste water and much of the
 suitable soil  is  in the valleys desirable for farming rather than on the high ground
 which is desirable for housing  (21).  In other areas where the soil itself is  suitable,
 soil absorption  systems are undesirable because of high ground  water levels such
that adequate filtration cannot be achieved before the effluent enters the ground
water reservoir.  This  is particularly important since the areas that use individual
waste disposal  systems also commonly have individual water supplies and ground
water pollution is a major concern.

 In some areas where septic tank systems are widely used, the disposal of the sludge
which must be periodically removed from the tank is a major problem.  The open
dumping of these sludges is understandably prohibited near any  population centers,
and many municipal treatment plants are unwilling or unable to  treat an additional
organic load.  Cases such as these emphatically point out the need for extensive,
comprehensive  planning before the decisions to  permit new housing developments
can be made.
                                        36

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Just as the streets and power lines in a new area must be carefully planned to
provide the most efficient and most economical service, the method of sewage dis-
posal  must be carefully considered.  In areas that are sparsely populated and not
likely to grow appreciably,  central water distribution and sewage collection systems
may be more costly than the value of the service they could supply.  In these areas the
population can be served best by individual systems.  In other areas the cost of
individual systems may be greater than the cost of equal or superior service supplied
on a community basis. Before the sewage disposal system can be specified, pre-
liminary projections of future expansion and development of the community is very
important,  for the  specification of either individual or community systems of waste
disposal could mean a great difference in the cost of  sewage disposal service.  There
are numerous cases where  individual systems  have been installed,  only to require
replacement with a community system at several times the cost if such a system had
been originally installed,  rather than after sidewalks, lawns,  and streets have already
been established.   Also homeowners who have  recently installed or repaired individual
systems usually oppose any movement to establish community service (21).  Similarly,
the per household cost of operating and maintaining an improperly designed or
unnecessary community waste disposal system can be prohibitive.  Also, in areas
with municipal water supplies where space is available and the soil suitable, individual
systems may not only be more economical but  help prevent stream pollution.  Pro-
perly  designed and maintained individual waste disposal systems in these areas would
probably not burden surface water quality nearly as much as the effluent from a
community waste system providing secondary treatment.  The importance of planning
for the overall requirements of a sewage disposal system in the total community
cannot be over emphasized  (18).

The choice of waste treatment systems now available is relatively limited.  Basically,
the choice is  limited to aerobic and anaerobic biological systems.  Septic tank, soil
absorption systems are by far the most inexpensive and dependable individual system.
However,  they are not suitable in some areas of the country arid other methods must
be used.  One modified version of the septic tank system,  involving waste separation
and a  redesigned soil absorption system, is now being marketed (108).

Individual aerobic treatment systems have been proposed; but while they produce
a higher quality effluent than septic tanks, aerobic treatment presents some of the
same  disposal problems and additionally requires maintenance and power not needed
in the septic tank system.   The purified liquid  effluent from these aerobic treatment
plants still contains organic matter, suspended solids, and possibly pathogenic
bacteria.  In  most  localities, the effluent from these systems must be discharged
to soil absorption systems to provide safe disposal.  Even if some means of dis-
infecting the effluent were provided, disposal to surface drainage would be unaccep-
table to many health officials, because malfunctions could occur without notice,
and it would be very expensive for the regulatory agencies to provide the equipment
and personnel needed for even minimum checking of effluent quality. Also many
homes are not located adjacent to streams or water courses into which the treated
                                         37

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 effluent could be discharged.  Future developments and new,  more reliable systems
 of control including service contracts for maintenance and performance checks,
 may make these devices more readily acceptable to health officials, but at present,
 if they are to enjoy wide usage, they must enable the effluent to be disposed to the
 soil more economically than from a septic tank.

 The University of California Sanitary Engineering Research Laboratory,  conducted
 a comparative study of a septic tank system and an aerobic treatment system (100).
 The effluents of the two units were very similar with regard to suspended solids and
 chemical oxygen demand.   The septic tank gave a much more stable performance
 and was  less subject to upsets.  The aerobic unit, on the other hand, gave an
 effluent which clogged the soil less severely.  Although these tests gave no clear
 advantage to either system, it is  important to note that the effluent from the septic
 tank flowed  up through a rock filter which, according to the report, was considered
 only to reduce the volume of the second chamber of the septic tank. This filter
 probably improved the septic tank effluent measurably.

 Studies conducted at the Ohio State University (64) and the Massachusetts Health
 Research Institute (19) found that the effluent from aerobic units was superior to
 septic tank effluent in suspended solids and BOD. Thomas  (87) suggested that with
 aerobic treatment units the soil absorption area could be reduced to 1/3 the area
 required with septic tanks.  In some states the permitted rate for applying aerobic
 effluent to soil absorption systems is substantially higher than for septic effluent.

 Much recent work has been done to provide sewage disposal systems compatible
 with growth  areas where continued development is expected,  and to develop other
 systems  suitable for isolated population centers  where no further development is
 anticipated.   In areas where housing development is expected to continue, it is
 desirable to install the sewerage system  as the homes are built, to avoid the double
 cost of temporary individual units and the higher installation  costs which prevail
 after development has occurred.  Such a  system must have very low operating costs,
 must be expandable,  and must fit into the overall plan for sewerage in the area.  One
 solution would thus be an expandable mobile unit or series of units, in which initial
 collection lines would not be too long, and which could be moved and expanded as
 population grew.  Oxidation or stabilization ponds have begun to receive wider usage
 in these situations.  One plan of development is to build the stabilization pond in a
 convenient location to serve the first homes constructed. When the builder is ready
to construct more homes he simply builds a new pond  down stream.  The old pond
 can be drained and reclaimed for building sites at a relatively low cost (23).  In spite
 of the attractive low cost features of the  stabilization pond, this method is not
 completely satisfactory because of the difficulty in controlling and removing algae
 growths and the detrimental effect on the effluent.  Also, there are advocates of
temporary schemes with higher unit costs which reduce popular resistance to
 establishment of a permanent system.  Stabilization ponds have been used extensively
 in warm  regions, but they have also been acceptable in the colder climates (50).
Whatever the type of treatment chosen for the developing areas, the most important
factor is to make sure the initial  sewerage scheme is compatible with the overall
long range plan.
                                       38

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The problem in isolated population centers is somewhat different.  The need is for
a permanent treatment system designed to give reliable, low cost treatment.   Several
types of treatment have been considered, including package aerobic treatment units,
small anaerobic units,  and oxidation ponds.  Package aerobic treatment units are
widely used in some areas.  Some are merely scaled down versions of a conventional
activated sludge plant,  but useful variations of the activated  sludge process such as
extended aeration and contact stabilization have also been developed.  There are
many reputable manufacturers of package treatment plants,  each offering some
special treatment feature for aeration, solids separation, etc.,  and careful study is
required to choose the  type that best meets the requirements of a specific situation.
A problem with many of these systems is the relatively uncontrolled discharge of
aeration tank solids during periods of treatment upset.  Stabilization ponds have also
given excellent sewage treatment for permanent installations when they have been
properly designed and are adequately maintained.

Anaerobic treatment systems have been used for sewage treatment for many years.
The Imhoff tank was used for many years before activated sludge and trickling filters
became popular.  Recently, the Public Health Service has investigated the use of an
anaerobic contact process in which the incoming sewage is filtered upward through a
bed of anaerobic sludge (104).  Private studies of anaerobic  sludge treatment units
are also being conducted (28).  The choice of community treatment plants  is again
dependent on the circumstances.  The number of people served, the money available,
the quality of effluent required, and the maintenance force available will govern the
final selection.
                                       39

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EQUIPMENT CURRENTLY MARKETED FOR TREATMENT OF WASTE FROM
INDIVIDUAL HOMES

In this section, the devices currently marketed for individual home waste treatment
are evaluated and compared as to first cost (equipment cost and installation expenses),
operating cost, and effluent quality.  The evaluation was conducted solely from in-
formation in the literature and from data supplied by the manufacturers; no actual
testing was performed on any of the devices.  For convenience in comparing the various
systems, we assumed the treatment devices to be installed at  "average" homes
with three bedrooms, four "average" family members, and located on soil with
poor,  average, or good (classification according to Thomas (87))permeability.  The
discussion of anaerobic devices and aerobic devices is separate.

ANAEROBIC SYSTEMS NOW MARKETED

Conventional Septic Tank
The septic tank is the most commonly used individual waste disposal system.  B
consists  simply of a container in which wastes are accumulated and digested under
anaerobic conditions.  Capacity and hydraulic design are the most important factors
influencing septic tank performance.  The capacity  is important to allow quiescent
conditions and sufficient time for sedimentation.  The capacity must also be sufficient
to dilute chemicals harmful to the digestion process and absorb surge flows from
laundry and bathing without discharging digesting solids.  Additional capacity is
required  for storage of the digesting solids.  The hydraulic design determines storage
efficiency and the extent of short circuiting and thus determines the percentage of
the capacity  that is effectively used.  Figure 3 showed the principal septic tank
features and figure 4 shows some of the common septic tank designs. The sewage
itself  contains the bacteria which catalyze the anaerobic decomposition of the solids
which settle  out.  The septic tank system has no moving parts and the only main-
tenance required is the removal of  solids which resist anaerobic  decomposition
and slowly accumulate in the tank.  The solids must be removed before  the effective
liquid capacity of the tank becomes too small to allow solid particles to  effectively
settle out.  Empirical formulas have  been suggested for the volume of solids in
the tank,  but the rate of solids accumulation depends on too many factors  (number
of people, type of wastes, design, size of tank, etc.) for such formulations to be
generally applicable.  Thus, the  time between required cleanings must be determined
by periodic examinations of the solids accumulated. The  average period between
cleanings is  usually two to four years.

The septic tank is usually constructed of precast concrete or steel, but brick, tile
and other materials are also used. The steel tanks are the least expensive, but
usually have a shorter life expectancy (seven to ten years). Many concrete, tile
and brick tanks, on the other hand, are still operating after more than twenty years
service.
                                        40

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Figure 4.  Common Septic Tank Shape (from Manual of Septic Tank Practice)
                                    41

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Treatment Costs - An adequately sized concrete tank can be obtained for less than
$120; installation of the tank may cost over $250.  The effluent from the septic  tank
must be discharged to a subsurface soil absorption field for final treatment because
the septic tank effluent is still not fit for surface disposal. The cost of the soil ab-
sorption system cannot be accurately estimated unless the absorption system design,
soil conditions, type of home and labor costs, are known.  For purposes of this
discussion we will assume, as mentioned in the introduction, a three-bedroom  home
with a four member family and we will theoretically design for a 20-year soil
absorption system life (23) and will use some average cost figures.  In a soil with
poor permeability, approximately 1600 square feet of soil interface costing approx-
imately $1600 to $2400 would be required.  For a fair soil, only 500 square feet at
$500 to $750 would be needed. In good soils,  170 square feet at $200 to $300 may be
sufficient.  Then, with a $14 per year maintenance charge (cleaning every  2  to 4 years),
the yearly cost for waste disposal would be $112 to $152 in poor soils, $57 to $70
in fair soils,  and $42 to $47  in good soils.  (Basic data from references 87 and 90).
These costs can also be approximately reported as a cost of $1.42 per 1000 gal.
in poor soils, $0.68 per 1000 gal. in fair soils, and $0.47 per 1000 gal.  in good
soils.

Effluent Quality - The following table lists a few treatment parameters for the
experimental septic tank used in studies at the Sanitary Engineering Center at the
University of California.  Effluent values are compared to the influent sewage values
in terms of mg/1.  (Recall that this system had a rock filter which probably  in-
creased removal percentages).  Aesthetically, the anaerobic effluent may be more
offensive than the raw sewage that enters the  tank,  because the products of
anaerobic oxidation are commonly odorous compounds.  Also, the bacterial  content
is often higher than that of the influent sewage.
                                      Septic Tank
Parameter         Raw Sewage          Effluent        % Removal

BOD                   150                75              50

COD                   310               160              48.4

Suspended Solids        185                50              73

Volatile solids          265               160              39.6
                                                    C
The coliform count of the effluent may be higher than 10  per milliliter, a number
which is 10,000 times the permissible level of 10^ organisms per milliliter  in the
recommended standards for surface water used for bathing (95).

A Variation of the Anaerobic System
A fiberglass septic tank system now being marketed boasts two significant changes
purported to make it advantageous over the common system.  The proper operation
of the system requires that wash waters be separated from sanitary and kitchen
                                         42

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wastes.  The sanitary and kitchen wastes can thus be held in the upper compartment
for a longer period of anaerobic digestion.  Under this arrangement, the sanitary
wastes receive more concentrated treatment and the bactericidal effects of some
detergents and household cleaning agents are avoided.  The waste wash waters are
conducted to a lower chamber where they are mixed with the effluent from the upper
compartment and undergo a somewhat shorter period of treatment.

This system is sold as a package unit including the soil absorption system which is
designed to be independent of the natural soil characteristics.   It is claimed that
sufficient sand and gravel fill is placed around the tank to allow all the effluent to
evaporate to the atmosphere if necessary.  Tests reported by the Sanitary Engineering
Research Company (108) indicated that the system can work even in impervious soil.
This system, like normal septic tanks,  has no moving parts, and the only main-
tenance required is periodic solids  removal.  Another feature available with this unit
is a 20-inch inspection and cleaning port which is extendable to the ground surface
and gives access to both compartments.

Treatment Costs  - The unit itself  costs $445.41 plus  shipping costs which will vary
with location.  The cost of the piping, installation labor, and the material for the
soil dispersion system would raise  the total system cost to approximately $1100.
These systems have been in operation for only a few years and no actual data is
available for estimating maintenance and life expectancy. However, based on the
manufacturer's claims, a soil system and tank life of 20 years with cleaning
required every four years  is believed to be reasonable.  Thus, an approximate yearly
cost of the system is $65.00.  These systems reportedly require the same seepage
area no matter what the soil conditions, so there is no recommended differentiation
for soil conditions. It seems certain,  however, that the life of the rock filter
system would  increase in good soil  locations.

Effluent Quality - This system is designed to produce no effluent to surface waters,
and it is  claimed to be operable with no liquid discharge from the rock filter at all.
The testing data in the reports from the Sanitary Engineering Research Company
list only  the suspended solids; reported removal of the suspended solids varied
roughly from 50% to 90%,  a range not significantly different from the values reported
for the experimental septic tank used by the Sanitary Engineering Research Center
of the University of California,  but  probably considerably better than the normal
septic tank.

Conclusions -  The major advantages of the anaerobic systems are their simplicity
and the resultant low maintenance costs. Of the anaerobic systems considered, the
data indicate that the conventional system is more economical in good to fair soils,
while the new system becomes competitive in fair soils and  definitely more
economical in  poor soils.   Thus the choice depends on the soil conditions.  Either
method should be reliable for use.  The reliability of the conventional septic tank,
soil absorption system, when well designed and properly maintained, is reflected
by its wide acceptance and  use.  Such a record is not available for the new system,
but the fact that  it has recently been approved by the Federal Housing Administration
testifies to its performance.
                                       43

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 SURVEY OF AEROBIC SYSTEMS

 Several types of treatment plants using aerobic,  rather than anaerobic, stabilizing
 processes to reduce solids and improve effluent quality are now being marketed for
 individual home use.   The aerobic oxidation system consists essentially of a com-
 partmented tank containing an aeration section and a settling section.   Most units
 are designed for continuous flow, but a few operate on a batch basis to avoid flow
 surges in the aeration compartment.  In the aeration compartment, the raw sewage
 is mixed with the oxygen in the air for relatively long periods of time.  Under the
 aerobic  conditions, the bacteria  in the sewage utilize the organic materials for
 growth and produce a flocculent bacterial sludge which rapidly absorbs nutrients
 from influent sewage.   In the settling chamber the bacterial matter is settled leaving
 a clarified effluent from which both dissolved and particulate organics have been
 removed.  Figure 5 shows a typical aerobic treatment unit.  Many of the marketed
 units include extra treatment processes before and after the basic aeration and
 settling  sections.

 Aerobic treatment systems do not remove unoxidizable and inert waste  constituents,
 unless provision is made to periodically remove  solids from the aeration section or
 subsequent treatment step.  However, unoxidized and inert solids are not necessarily
 discharged from the settling section on an even basis.  There is a tendency for solids
 to build up to an unstable level, followed by periodic discharge from the system.

 The effluent of the aerobic system is generally better than that from an anaerobic
 system.   Most units claim treatment comparable to municipal secondary treatment
 (approximately 90% BOD reduction and 80% reduction of suspended solids).  A major
 advantage of the aerobic effluent  compared to the septic tank effluent is its lesser
 clogging effect in soil absorption systems  (87).  Disadvantages of the system are
 higher operating costs, greater susceptibility to shock loadings of concentrated
 wastes and to harmful  chemicals, and the variations in effluent quality due to such
 treatment upsets (100).

 In the survey of individual treatment units  as many manufacturers as possible were
 contacted (the manufacturers supplying information on individual home treatment units
 are listed in the appendix (table 1A)).  According to one manufacturer, the individual
 home treatment market has been in  a constant state of flux.  He reported that there
 had been twenty-five entries into the home waste  treatment field since 1955 and that
 of these only fourteen were still in business.  Eight of these fourteen had entered
the market in the last three years.   These figures indicate that there is a great
 interest in and a need for an individual treatment system to serve certain areas,
but also that many of the treatment systems marketed have been unacceptable and
probably have created a poor public opinion of the industry.

 Most manufacturers were reluctant to release sales figures, but from the data
obtained  we estimated that approximately 20 to 30 thousand of the aerobic units
have been installed, primarily by a few of  the more reliable manufacturers. The
correspondence and catalogues  received from the various manufacturers have been

                                         44

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Inlet
                 aeration chamber
overflow
 weir
I
                                                            .outlet
 settling
 zone
                                             sludge return
             Figure 5.  Basic Design of Aerobic Treatment Units
                                 45

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studied in detail,  and the salient design, construction,  and treatment features are
discussed below.

Pretreatment
Pretreatment of the sewage is not essential for aerobic treatment, but several of the
manufacturers do provide a pretreatment before aeration.  One manufacturer uses a
grinder to reduce the waste material to small particles which are more rapidly
oxidized in the aeration chamber.  Another manufacturer uses an anaerobic chamber
in which solids are settled and organics are partially digested before the aeration
chamber is reached.

Aeration Chamber
All the units attempt to mix air with the sewage, but the means of mixing vary
considerably.  The greatest number of units installed utilizes mechanical mixers
which physically mix the air with the wastes and at the same time provide continuous
mixing of the liquid.  Many of the remaining units blow a fine stream of compressed
air bubbles into the sewage to provide oxygen, and one system uses a  vacuum aspirator
system to draw air into the waste fluid which is mixed by the same pump that creates
the vacuum,  A Swedish unit (not yet marketed) utilizes a helix in a half cylinder
trough for aeration and agitation.  The rough surfaces of the helix pick up a thin
film of waste which is exposed to the air and oxygenated during half of each evolution.
The bacterial scum produced on the surfaces is similar to activated sludge solids.

Solids Separation
There are also many variations  in the method of separating the bacterial solids from
the effluent.  The most common system is a continuous flow-through tank in which
there is no agitation and the solids  settle to the bottom while the clarified liquid flows
out.  There is usually a baffle to prevent floating solids from entering the effluent.
The settled solids are usually returned to the aeration chamber by gravity or by a
pump.  One system which has been developed and patented but is not currently marketed
provides for completely quiescent settling.  Another patented system  (not currently
used in individual units though apparently  adaptable) uses  a slanted tube system in
the settling chamber (27) to provide better settling.  Two manufacturers enclose the
aeration section in a bag filter which allows only solids smaller than the filter mesh
to escape from the aeration system. Another unit has a submerged, fixed biological
filter which effluent flows up through following  the settling chamber.

ginal Treatments^
Many of the treatment units come equipped with or have available a variety of post
treatment systems designed to make the effluent more amenable to disposal. The
most common post treatments are disinfection  of the effluent and removal of suspended
solids by filtration.  Chlorine, ozone,  and other chemicals as well as pasteurization
have been suggested for disinfecting the final effluent.  One unit relies heavily on
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super chlorination to make its effluent acceptable for disposal. In another system,
the effluent is filtered through a particulate and carbon adsorption filter and then re-
used as a toilet flushing liquid.

Economics of Aerobic Treatment Systems

Obviously,  the many different aerobic treatment designs vary as to purchase price
installation and operation.  However, the systems have  sufficient characteristics
in common to allow an approximate table of purchasing and operating costs to be
established.  All the systems are designed to provide aerobic oxidation of house-
hold wastes,  a process that is time-dependent.  Therefore,  each system must provide
an aeration chamber in which the sewage is detained long enough for the oxidation
to occur.  In  most cases,  this requirement is  simply met by a tank large enough to
provide the required detention.  The National Academy of Sciences  Report on
"Individual Household Aerobic Sewage Treatment Systems" (60) recommended a
Volume in the aeration compartment of 67 gal. per person (no garbage  grinder) or
100 gal. per person with a garbage grinder.   Since most systems are planned for
at least a six-member family, the volume of the aeration chamber is usually 4 to 6
hundred gallons.

Oxygen requirements can also be treated in general terms.  For design purposes,
the raw sewage is generally considered to have some average oxygen consuming value
which requires a certain amount of oxygen.  Although the efficiencies of supplying
this oxygen necessarily differ, the variance  is probably small in a well-maintained
system.  Therefore, it is  assumed that, in general,  the installation and operating
costs as derived from several of the reliable systems are approximately comparable
for the basic  aeration, solids-separation system.  The approximate costs of aerobic
systems are listed below.   Values are also included for some of the common means of
final treatment.

                              TREATMENT COSTS

Purchase and Installation Cost                           $800 to $1600

Operating Costs (per year)

    Electricity                                         $ 25 to $ 100
    Service and Maintenance                             $ 30 to $  50

Filtration
    Initial Cost                                         $150 to $ 200
    Yearly Operating Cost                              $ 10

Disinfection

    Initial Cost                                         $150 to $ 600
    Yearly Operating Cost                              $ 20 to $  50.
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Using the lower estimated costs without including post treatment costs, the basic
cost of treatment is $95 per year  or abour $1. 02 per 1000 gal.; inclusion of filtration
and disinfection would increase this rate to $1.34 per 1000 gal.   Thus except in poor
soil areas aerobic treatment is more costly than anaerobic waste treatment without
even considering disposal of the aerobic effluent.

Discussion of the Aerobic Treatment Systems
A comprehensive review of aerobic treatment systems,  including a general review
of treatment unit objectives, general construction and operating criteria, and a
discussion  of the conditions wherein aerobic systems should be used,  is presented
in the National Academy of Sciences report "Individual Household Aerobic Sewage
Treatment  Systems" (60).

High costs  are a major problem with the aerobic treatment systems and discharging
the effluent to surface drainage rather than to a subsurface soil absorption  system
has been suggested as a means of cost reduction.  Some of the treatment units do
consistently produce an effluent suitable for surface drainage. However, other
units obviously have not met acceptable standards and in many areas surface disposal
of aerobic effluent is not legally permitted.  The reluctance  of public officials  to
permit surface disposal is easily understood. Even for treatment units consistently
producing a good effluent it takes  only one malfunction to release contaminated water
which could endanger the health of the community.  Health officials do not have specific
criteria at  this time to evaluate the many different types of treatment units, their
expected performance, or the  maintenance problems that might be encountered; and
rather than permit the development of a possible health hazard, a common  reaction
has been to prohibit all surface discharges from individual treatment units. Also,
health officials realize that they could not adequately police the number of surface
discharges that could occur.  The quality of effluents discharged to storm drains,  the
most convenient disposal method, would be even more difficult to monitor.

Sludge disposal is also a problem with aerobic systems. When the extended aeration
system was first proposed it was believed by many that all organic material would be
eventually oxidized to gaseous products and water.   However, just as in the septic
tank some organic materials resist digestion, as do nearly all the inorganic solids,
so that there is a gradual build up of solids which must be removed to prevent the
periodic  discharge of slugs of sludge particles in the effluent. As with anaerobic
systems  the rate of accumulation depends on the system design and operation.  Thus
regular inspection is a necessity.

The further growth of the market for individual home aerobic systems thus seems
dependent on the inclusion of adequate safeguards against unattended malfunctions
through better instrumentation, better service contracts, and greater cooperation
among the homeowners, the equipment manufacturers,  and the public officials.
The information supplied by the manufacturers indicates that they are attempting to
achieve this goal.  No completely satisfactory system has yet been proposed,  but
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many advancements have been made and surface discharge is gaining acceptance in
more areas as system improvements and safeguards are supplied.

Each treatment system has features which make it more suitable for certain applica-
tions and each situation will demand a careful examination of specific requirements
before a particular treatment unit can be chosen.

DISCUSSION OF THE FUTURE DEMAND FOR INDIVIDUAL WASTE DISPOSAL SYSTEMS

PRESENT STATUS OF INDIVIDUAL HOME SYSTEMS
The wide-spread growth in the use of the septic tank soil absorption system continued
until today more than twenty-five percent of the 60 million individual housing units
in the country depend on septic tank,  soil absorption type sewage disposal.  Of the
approximately two hundred million people living in the United States, roughly one
hundred twenty-six million are connected to central sewerage systems, while about
seventy-four million use individual disposal systems (92).  Using the national average
of three persons per household,  (89) these seventy-four million persons can be
roughly equated to approximately twenty to twenty-five  million individual disposal
systems.

The first nationwide data on the numbers and types of household water and waste
disposal systems was collected by the Housing Census of 1960 for, communities of
twenty-five thousand or  less.  These data showed a  total of nearly fourteen million
septic tank or cesspool systems. Including the approximately 1.4 million new homes
equipped with septic tanks that have been constructed since 1960 (reports from the
Federal Housing Administration), and allowing  for a small percentage of septic tank
installations that are still operating in cities of more than twenty-five thousand people,
the number of septic tank or cesspool installations now in use can be roughly fixed
between fifteen and seventeen million.

A relatively small number of individual aerobic type treatment devices are now in
operation.  The total number of these installations is considerably less than fifty
thousand. The five to ten million remaining households use primitive waste disposal
methods or  discharge the untreated wastes directly into adjacent water courses.
The number of households reportedly having no plumbing at all, and specifically no
flush toilets, roughly coincides with this  number of  five to ten million remaining
households.   This indicates that most of these homes use a primitive waste disposal
method such as the pit privy.

Future Projections for Individual Home Systems
The population of the United States has increased at a uniformly high rate since the
sudden growth surge following World War n and the demand for housing has increased
correspondingly.  However, the actual demand  for new homes is primarily a function
of new family formation (21) and the preference of the new family for an apartment
or an individual home.   The children born in the high birth rate period of the late
forties are now coming to marriageable age and the rate of new family formation is


                                        49

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rising.  At the same time, the percentage of multifamily dwellings is increasing.
Of course,  many of the newly formed families have chosen apartment dwelling from
financial necessity, but the number of families who actually prefer apartment living
seems to be increasing.  This is partly a result of the growing mobility of our society.
Many families move frequently as jobs change or better opportunities become available
in other cities and other states.  The task of repeatedly buying, selling, and main-
taining property becomes very burdensome.  Apartments also provide other advantages,
such as recreational facilities which are not available to most homes.  Also, modern
apartments are providing the privacy and work space severely lacking in older
apartments.  This trend toward permanent apartment living is reflected in the in-
creasing construction of apartments with two or more bedrooms as more families
continue to choose apartment living as their families grow larger. The percentage
of apartments constructed with two or more bedrooms rose from 47% in 1964 to 58%
in 1967  (Economic News Notes, Sept. 1968).

If these trends continue, the demand for individual housing will probably not increase
as rapidly as the population.  However, recent trends indicate that most of the
individual homes that are constructed will probably be built beyond the reach of
existing central sewerage systems.  Nearly all the recent population gains have taken
place in metropolitan areas as rural population has actually decreased. However,
most of the metropolitan growth has been on the fringes of the cities.  From 1950 to
1960,76% of the metropolitan growth was outside the central cities.  From 1960 to
1966 this figure increased to 87% (88).

However, the percentage of those new individual homes that will use individual
treatment systems will be difficult to estimate. The knowledge gained in the many
studies on septic tanks and soil absorption systems and the development of alternative
methods of community waste treatment have helped to decrease the rate at which new
septic tank soil absorption systems are being installed.  Records of the Federal
Housing Administration show that the percentage of new homes built with septic tank,
soil absorption systems has  steadily decreased.  In 1960, the percentage of new
individual homes with septic tank, soil absorption type systems was  approximately
18 percent.  By 1967 the percentage had dropped to approximately 10 percent.
Housing developers and public health officials now recognize that septic tank soil
absorption systems are not suitable for all areas.  Also developers are recognizing
the economic advantages of comprehensive planning. It is important to emphasize,
however, that the actual number of septic tank soil absorption systems and other
individual systems being installed is still very large, and will continue to be for some
time in the future.  The need for more research on treatment systems for isolated
households and the distribution of the information on individual systems to the
homeowners will increase rather than decrease in the future.

Individual aerobic  systems will probably gain a larger share of the home waste
treatment market in the near future as their overall economic superiority over septic
tank systems for certain soil conditions (87) becomes more widely known.  Any
                                       50

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large gains, however, will depend on the devebpment of reliable automatic controls,
fool-proof systems for effluent disinfection, the development of low cost service
contracts, and above all, the confidence of health authorities.

Although the rate of increase of individual systems should decline, the number is
already very high and as water quality requirements become more exacting the prob-
lems of individual treatment will be much greater.  Thus, future research cannot be
concentrated only on the types  of sewage treatment now  commonly used.  Other scien-
tific disciplines should be  surveyed for possible processes and technology to help
meet the requirements of the future (59).  Some of the advanced waste treatment
techniques that are now being tested are reviewed in a later section (section V),
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                                      IV
               HOUSEHOLD PLUMBING FIXTURES TO REDUCE
                       WATER USAGE REQUIREMENTS
INTRODUCTION
This section presents a study and engineering evaluation of possible changes in
household plumbing fixtures to reduce water usage requirements,  and hence reduce
the flow of waste water from households (Task I).  Specifically, the following program
was undertaken: (a) a review of previous studies,  (b) a survey of plumbing fixtures
that have the potential of saving water, and (c) evaluation of the feasibility of using
these fixtures  in the household on the basis of quantity of water saved and cost (fixture
cost plus installation labor).

REVIEW OF PREVIOUS STUDIES
The Cornell University study "Bathroom - Criteria for Design" was reviewed (45).
While this report was very interesting,  it was slanted more toward physiological,
psychological, and aesthetic improvements in design (i. e., human engineering)
rather than towards a reduction in water usage. For example,  the report encourages
the use of the urinal for reasons of convenience and aesthetics, but does not mention
its potential for water savings.  Many of the  design concepts presented would use
more water rather than less.

Very little information was found in the open literature on water savings to be
realized by the installation of special valves  or fittings. In most cases, these
fixtures are designed primarily to conserve hot water and reduce fuel costs. Reduced
hot water use  is particularly helpful where the  hot water supply is heated instan-
taneously from a house heater.

The British have been very interested in economizing on the use of hot water in
lavatory basins since fuel costs are high in the United Kingdom.  In one series of
tests run in large office buildings,  wash basins were fitted with thermostatically-
controlled, single  outlet spray taps (26,  78).  Test results showed one-half to two-
thirds  reduction in water consumption for washing as compared to standard basins
fitted with 2 faucets and a drain plug.

The  British have developed a dual cycle water  closet, one flush cycle for urine, the
other for solid wastes (26, 70). The water closets operate on a syphon system with
a very shallow trap seal.  The flush for solid waste is 2.5 gal. (2 Imperial gal.) as
compared with 5 to 6 gal. in the standard American fixture.  The  urine cycle uses
only 1-1/4 gal.  These cycles are actuated by a short sharp stroke or  pull for the
smaller amount of water, or a longer sustained pull for solid's flushing (see fig. 6).

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  —  - one gallon* - —
     , one gallon*
   potential  saving
A-handle,   B-air intake,   C-siphon,   D-piston
When the piston  (D)  is  held  open,  the air intake (B)
is closed and  the  whole contents of the tank are
siphoned.

When the piston  is opened, then released, the air
intake is open and the  siphon breaks when half the
tank is empty.


* Imperial gal.

             Figure 6. Dual Flush Toilet Tank
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 The test results using this dual flush cycle in low income flats showed a mean
 saving of 27% of the normal water used.  (R should be noted that "normal" for water
 closets in England is only 2 Imperial gal.  per flush).

 These studies have been going on in the United Kingdom since 1956,  and the reports
 noted above are quite detailed.  However, as  noted, the tests have been directed
 towards large office buildings or multiple family apartments rather than individual
 homes.

 The reason for this greater concern for water economy in Europe is the higher
 water costs and the greater public  awareness of these costs.  Most services in the
 United Kingdom are metered.  In the United States, however, public water supplies
 in big cities (especially in the older sections) are not metered, and water is wasted
 because so much of it seems available at no direct cost to the user.

 SURVEY OF PLUMBING FIXTURE MANUFACTURERS
A survey of manufacturers of plumbing fixtures and household appliances was made
 to determine the availability (commercial or  under development)  of hardware devices
 that have the potential of reducing water consumption.  The companies  responding
 are listed in Appendix HA.  The information furnished leads us to believe that the
 manufacturers of plumbing fixtures and equipment are cognizant of the  problems
 requiring reduction of water consumption and waste water flow reduction in house-
 holds.  The results of this survey are summarized below.

 Faucet Flow Reduction Devices
 Several manufacturers currently market limiting flow valves and mixing valves that
 restrict the maximum flow rate (29,  67,  46).  These valves provide maximum water
 savings with showers although they can also be used in kitchen sinks and bathroom
 lavatories.  One company offers an inexpensive flow reduction device which is pres-
 sure compensating, fits in the supply lines to faucets or showers and reduces the
flow from conventional fittings.

 For shower heads, the flow rate with a limiting flow valve is usually restricted to
 about 3 gpm. A water savings (for showers)  of 50 to 70% is claimed, but independent
test data are not available.  Obviously, the quantity of water saved will be dependent on
 many factors, including the water pressure available  and the habits of the user.

 For lavatory and kitchen sink fittings,  the flow is usually restricted to 2.5 gpm for
 each valve.  Water savings are claimed to be "up to 50%", but again test data for
households is not available.
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An important advantage of the flow reduction devices for showers and sinks is the
savings in fuel for hot water heating.  A reduction in total hot water consumption of
25 to 40% is claimed; this can provide a reduction in fuel cost that is the same order
of magnitude as the total  savings in water cost.

A very simple water-saving device already in wide use is the aerator used on faucets.
Although intended principally as an anti-splash device, it does provide some water
savings.  It is estimated  that the faucet aerator reduces water consumption at kitchen
and lavatory sinks by approximately 25%.

Another plumbing device  which  promotes some water savings is the thermostatic
mixing valve, a device which permits mixing of hot and  cold water to attain a desired
temperature level.  Once adjusted,  the proportion of hot and  cold water is varied
automatically by a bi-metallic coil as the temperature or pressure of the  incoming
water is varied.  Thus, the bather is not in danger of being suddenly scalded or
doused with cold water as others in the household stop using or begin using water
at other fixtures.  This diminishes the danger of falls as bathers try to avoid the
sudden changes in water temperature while standing on slippery tub or shower
floors. Besides advantages in  safely and convenience, the thermostatic mixing
valve  offers the opportunity for moderate savings in water  consumption. This device
enables the bather to turn the shower off while soaping and to be able to have the
same  temperature when the water is turned on for rinsing.  This saves the water
that would be wasted as the water temperature is readjusted before rinsing or the
water that would be wasted if the shower were left on in order to  avoid the problem
of adjusting the temperature again.

Water Closets
A standard U.  S. water closet with a 4 gal. tank will, in most cases, deliver about 5
to 6 gal.  of water from the time the handle is tripped to the time the tank refills.
This is considerably more water than is really necessary. U.  S. manufacturers now
market shallow-trap toilets that use about one-third less water, i. e.,  about 3.5
gal./flush (99).  One such unit is shown in figure 7.

As noted earlier, the British have pioneered in the use of dual flushing cisterns
(2-1/2 gal. or 1-1/4 gal./flush).  This is now a mandatory requirement  in certain
parts of the United Kingdom and has been included in the revision to British Standard
1125 (41).  This same reference states:
    "With regard to U. K. type closets, you will note that these' are designed
    to clear the pans with one 2-gallon flush.  There would be no difficulty in
    designing a syphon closet,  suitable for the American bottom outlet require-
    ments, which will also work efficiently with a 2-gallon (Imperial) flush.
    We would also mention that in England cisterns are operated by syphons
    which prevent the water running away to waste into the W. C. pan."
                                       55

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Figure 7.  Shallow Trap Water Closet
                   56

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This dual cycle water closet would provide a 70 to 75% reduction in water usage
(as compared to the common U.S. toilet).  However, it should be noted that this
design may not meet the requirements of the plumbing codes in some U. S. localities.

Batch-type flush valves (instead of a tank) are widely used in commercial buildings
and apartments, and these could also be used in homes.  They can be set to deliver
from 0.5 gal.  to 4 gal./cycle (66).  However, they would require a larger diameter
water line than is  now used to supply  a flush tank.

One of the most interesting developments in water closets is the Liljendahl* system
(Swedish) which is being investigated for use in this country by the Eljer Plumbing
Company (103). This system uses air (rather than water) as the transport fluid and
requires only 0.5 gal. water/flush.  Plastic pipe  (2" dia.) is used for the drain lines,
and a waste receiving tank and vacuum pump are needed.  The system is in use in
hotels, motels, apartment houses, and other large buildings in Sweden and in the
Caribbean Islands; it has not, as yet, been used in individual homes. (See figure 8).

Urinals
 Wall type urinals of compact design for home installations are available (99).  These
 urinals have batching-type flush valves set at 1.5 gal. water per use.

 The use of urinals in the home would have two obvious disadvantages:

    1.   additional bathroom space would be required, and

    2.   the units would serve male household members only.

 Female urinals are used on a limited basis in a few office buildings and factories, but
 their use in homes is not warranted.

 Automatic Clothes Washers
Water requirements for washing machines vary considerably, depending on design,
from about 20 to 33 gal./cycle.

One of the features used with automatic washing machines to save water (and detergent)
has been to store and reuse the wash water.  However, this feature has not proved
popular with the consumer as indicated by the following quote (72):

     "The automatic washer is but one element in the home laundry process.
     Fabrics, detergents and laundry aids have far more effect on water than the
     machine does.  For some time we have marketed what we call "Suds Miser"
     models of our washers.  These utilize water twice and at one time represented
     a significant share of sales.  In recent years homemakers have more or less
     rejected the suds saver feature .  .  .  Changes  in fabrics and detergent tech-
     nology have meant the need for more water.  Permanent press items, for in-
     stance, require more water for washing because they must go through a gradual
     cool down.  There is nothing that we,  as manufacturers of equipment, can do to
     lessen the need for water  in the washing process because of developments in
     fabrics and laundry aids."
*Mention of a commercial product does not imply endorsement by the Federal Water
  Pollution Control Administration.
                                     57

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water trap
                 timing and water valve
  vacuum  pump
/    vacuum
f   receiving
\      tank
       (may be  located above or below toilet)

         Figure 8. Vacuum Toilet System
                      58

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Another feature now being marketed is a loading door which acts as a weighing
scale to measure the amount of clothes to be washed.  Knowing the weight of the
clothes, the user then selects only the amount of water required to wash a particular
load  size.  In other words,  a water level control is provided which can be set to
avoid using unnecessary extra amounts of water (34).

Another means of reducing the amount of water  is  by the use of front loader washers.
The washer tub rotates on a horizontal axis and tumbles  the clothes through the water.
This type of washer uses approximately half as  much water for a particular load size
as compared to the top loading washers and costs  about the same. Early homewashers
{patterned after commercial laundry washers) were of this type, but consumer
acceptance was poor.

Automatic Dishwashers
In recent years the number of homes with automatic dishwashers has been increasing
fairly rapidly.  Depending on the design, water  requirements vary considerably,
i.e., from about 6 gal. to 19 gal./cycle (30).  Based on studies that indicated an
average of 1-1/3 uses/day,  the average household uses 13 to 19 gal./day in their
automatic dishwasher (96).  These values do not include water used in rinsing the
dishes before putting them in the dishwasher or the water used in washing particular
items.  None of the manufacturers contacted indicated any design features specifically
intended to reduce water consumption.

Garbage Disposals
No information on potential water savings for food waste grinders was received from
manufacturers.  This is understandable since published  information indicates that
total water consumption in the home is not significantly increased by the use of
garbage disposals (16).

Other Fixtures
Except for the devices and features previously described,  none  of the manufacturers
contacted indicated any plans to market fixtures or appliances designed to reduce
water consumption.  If anything, the comments received indicated that water require-
ments  for household appliances would increase  rather than decrease.

HOUSEHOLD FEASIBILITY OF PLUMBING FIXTURES

Cost Estimates
Cost estimates for each type of water savings device were made for both old con-
struction (remodeling) and for new home construction.   For old homes,  the purchase
price of the hardware device, as determined from manufacturers1 prices, was used.
For  new homes the difference in price between  the water savings  device and the con-
ventional hardware was used.

Installation costs were also estimated for old and new construction.  A labor rate
of $7.50/hr was used. Installation material (e.g.,  piping) was included under

                                       59

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material costs.  Again, for old homes the total installation labor was used, while
for new homes the difference in labor (between the water savings device and
the conventional hardware) was used. The cost estimates are summarized in table
IX.

Costs for the Liljendahl vacuum flush system were estimated by Eljer (103) for
individual homes and for groups of 100 homes.  These cost estimates are shown in
Appendix IHA. and were used in table IX.  This system is not currently being marketed
for use by single homes and would require a waste storage tank (about 50 gal.) and
a vacuum pump for each home. The tank would be discharged periodically into the
main drain line.

The plumbing devices listed in table IX are the following:

    1.  Shower with limiting flow valves used in place of conventional shower.
        Maximum flow rate would be 3.5 gpm.

    2.  Bathroom lavatory with limiting flow valves (hot and cold water) in place
        of conventional faucets.

    3.  Kitchen sink with limiting flow valves (hot and cold water) in place of con-
        ventional faucets.
    4.  Aerator faucets  for bathroom lavatory and kitchen sink.

    5.  Water closet with one batch-type flush valve (3.5 gal. /flush) in place of
        the conventional tank. A 3/4" copper tube water line is used in place of
        a 1/2" line.

    6.  Water closet with two batch-type flush valves (3.5 gal. /flush for solids or
        2.5 gal. /flush for urine) in place of conventional tank.  Again,  a 3/4"
        water line is used.

    7.  Urinal with batch-type flow valve (1.5 gal./flush) in addition to conventional
        water closet.

    8.  Water closet with shallow trap (3.5 gal./flush) in place of conventional water
        closet.

    9.  Dual cycle water closet (2-1/2 gal./flush for solids or 1-1/4 gal./flush
        for urine) in place of conventional water closet.

   10.  Liljendahl-type vacuum flush toilets (0.5 gal. /flush) in place of con-
        ventional water closet.   Drain lines are 2" plastic pipe.  A central
        collection tank with dual vacuum pumps is used for a group of 100 homes.

   11.  Same as No.  10  but with tank and vacuum pump for each home.
   12.  Washing machine with water savings feature  such as weighing device  and
        level control for partial  loads.

   13.  Thermostatic  mixing  valve used in tub and shower.

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Water Savings
The quantity of water saved by various hardware devices (as compared to a con-
ventional fixture) was estimated.  Results are summarized in table DC.  The use
of limited flow control valves for showers would give a savings up to 6 gal. /person/
day,  or 24 gal./day for a 4 member household.  (Item 1).  Limiting flow control
valves for the lavatory or kitchen sink result in a relatively small water savings
(Items 2 and 3).  Aerator faucets for kitchen and lavatory (assuming no dishwasher)
could give a savings of 2 gal./day for a 4 member household (Item 4).

The use of batch-type flush valves for toilets (rather than tanks)  would result in an
average water saving of 1.5 gal./operation.  In a household of 4  with 5 uses/day/
person, this would give a savings of 30 gal./day (Item 6).

The use of urinals  in the home with a batch-type flush valve, assuming 2 male
members, and 4 uses per male household member would result in a  savings of  3.5
gal.  per use or 28  gal./day  (Item 8).

The use of the shallow-trap water closet would give a water savings  of 7.5 gal./person/
day (Item 9).

A dual flush cycle water closet (British type) would result in a savings of 17.5
gal./person/day or 70 gal./day for a 4 member household (Item 10). The Liljendahl
vacuum flush system would save 23 gal./person/day (Items 11 and 12).

A washing machine with the  suds savings feature or with a level  control for small
loads could save an estimated 5 gal./cycle.  Based on 6-7 loads/week,  water
savings would be about 5 gal./day (Item 13). The savings with the thermostatic
mixing valve would probably amount to less than two gallons per shower which  is
equivalent to approximately $1. 00 per year per person in water, fuel and sewage
costs.  Since thermostatic mixing valves presently cost about  $80.00 and  installation
would be about $20.00, the thermostatic  mixing  valve cannot be recommended on
the basis of water  savings alone. Selection of this device should be for comfort,
convenience, and safety; water savings are just  a side benefit.

Cost Evaluation of Plumbing Devices
In order  to evaluate the relative merit of the various plumbing devices presented
in table K,  the following ratios were calculated for each plumbing device:

                              Total Cost (New Construction)
                                Water Savings (gpcd)

Obviously,  the lower the ratio,  the more desirable the plumbing device.  Results
are presented in table X (in order of decreasing desirability).
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             Table IX.  Water Savings vs Cost For Plumbing Devices
Hardware Device
Water Savings    New Construction     Old Construction
                 Estimated Cost       Estimated Cost
                        Installed             Installed
gpe<3  -*- gpd*     Matl.     Cost        Matl.     Cost
2
7.5
8
30
80
25
90
40
80
75
100
105
  1.   Limiting Flow     6       24       15      15
      Valves for
      Shower
  2.   Limiting Flow     0.5      2       25       25
      Valves for
      Lavatory

  3.   Limiting Flow     0.5      2       25       25
      Valves for
      Kitchen Sink
  4.   Aerator for        0.5      2        2        2
      Lavatory and
      Kitchen Sink
  5.   Thermostatic
      Mixing Valve

  6.   Batch-type
      Flush Valve
      (1) for Water
      Closet
  7.   Batch-type Flush  15.5      62       55       70
      Valves  (2) in
      Dual Cycle

  8.   Urinal with          7       28      125      148
      Batch-Type
      Flush Valve
 9.   Shallow Trap
      Water Closet

10.   Dual Cycle
      Water Closet

11.   Vacuum Flush
      Toilet (100
      Homes)

 -••  gal/capita-day (gal/person/day)
 *  4 member household
 ** Negative cost, i. e.,  cost reduction
                                          62
                                                           35
                                                           45
                                                           45
                                                          120
                                                          150
                                                 50
                                                 68
                                                 68
                                                158
                                                175
7.5
17.5
22.5
30
70
90
20
10
v
20
10
(110)**
80
100
_
110
130
295

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                                Table IX.  (Cont'd)

                       Water Savings   New Construction     Old Construction
                                       Estimated Cost       Estimated Cost
                                               Installed             Installed
 Hardware Device       gpcd +  gpd*    Matl.     Cost       Matl.     Cost

12,   Vacuum Flush     22.5      90      -      1115          -        1520
     Toilet (Single
     Homes)

13.   Washing Machine   1.2       5      35        35          35         35
     with Level
     Control
 +  gal/capita-day (gal/person/day)
 *  4 member household

 ** Negative cost,  i. e., cost reduction
                                       63

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 From these results the following conclusions are drawn:
     1.   Limiting flow valves appear to be justified for showers and should be
         further considered.
     2.   The vacuum flush water closet can only be justified (economically) for
         groups of homes or  multi-family dwellings.
     3.   Of the various water closets and urinals considered, the dual cycle water
         closet appears to be the best approach for sanitary waste and should be
         further considered.
     4.   Aerator faucets, where not already in use, should be required.

     5.   The other plumbing  devices listed do not appear to be warranted.

The above conclusions are tentative in that they are based on the cost/water savings
ratio only.  Obviously, there are other important considerations, e.g., consumer
acceptability (see section VII).   The most desirable plumbing devices are discussed
further in section VI and compared with other alternatives, such as water treatment
and reuse.

Although the available data indicate that the vacuum flush toilet system has many
economic and water  conservation advantages, the group application of the vacuum
flush system will not be considered further in this  study since our primary concern
is for problem  solutions that can be undertaken by  individual homeowners.  It is,
however,  recommended that  further studies be conducted and the results made
available to contractors and real estate developers who work with multiple dwelling
unit systems.
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                       Table X. Cost Evaluation Ratio
                           _ Total Cost (New Const.)
                             Water Savings (gpcd)
Item No. (From
table IX)	             Hardware Device                R_
*Negative Cost,  i. e. cost reduction
11.     Vacuum Flush Toilets (100 Homes)                    (4.9)*
10.     Dual Cycle Water Closet                              0.6
 4.     Aerator Faucets for Sinks                             1
 1.     Limiting Flow Orifice for Shower Head                 2.5
 9.     Shallow Trap Water Closet                            2.7
 7.     Batch-type Flush Valves (2) in Dual Cycle              4.5
 6.     Batch-type Flush Valve (1) for Water Closet            5.3
 8.     Urinal with Batch-Type Flush Valve                   21
13.     Washing Machine with Level Control                  29
 5.     Thermostatic Mixing Valves                          45
 2.     Limiting Flow Valves for Lavatory                    50
 3.     Limiting Flow Valves for Kitchen Sink                 50
12.     Vacuum Flush Toilet (Single Homes)                  50
                                   65

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                  POSSIBLE TECHNIQUES FOR IMPROVEMENT
                     OF HOUSEHOLD WASTE TREATMENT
 There was little progress in water and waste treatment technology for thousands of
 years.  The ancient Egyptians knew the principles of most of our present methods
 for purifying drinking water such as filtration, carbon adsorption, exposing to sun
 light, and filtration. Although sewage was generally not even treated until after the
 middle of the nineteenth century,  the water and waste treatment methods most common
 today (filtration,  sedimentation, disinfection and biological treatment) were all in
 practical use by the early 1900's.

 Today these methods are no longer sufficient to treat the large quantities and high
 concentrations of wastes from our cities and industries.  Many locations already
 require almost complete waste water  renovation to prevent nuisance conditions in
 the surrounding waters.

 To meet these more stringent treatment demands, additional technology is being
 developed and borrowed from other disciplines.  The government has initiated many
 of the new developments through its own research laboratories and the sponsorship
 of private research and development.   The government has been instrumental in
 many developments through its support of aerospace and ocean exploration programs
 which require exacting water and waste management systems and through sponsorship
 of research on advanced waste treatment techniques and in the. demineralization of
 saline waters.

 The marine industry has long been confronted with the problem of limited fresh
 water and the disposal  of wastes.  For years, the practice in all sizes and types of
 watercraft was  simply  to discharge sanitary wastes overboard and depend on the
 dilution capacity of the body of water to render the wastes  harmless and inoffensive.
 Although this practice was acceptable at first when there were very few  boats and
 relatively little waste matter, the numbers of watercraft have increased rapidly,
 especially in the recreational field, and the wastes discharged are no longer
negligible. Also, watercraft waste discharges are usually concentrated in certain
areas and at particular times (summer, weekends,  holidays) which usually coincide
with the heaviest water usage for fishing,  swimming, and other water contact sports.
 The marine industry has attempted various methods for solving this problem.   These
methods range from relatively simple methods (closing marine toilets and not using
them, the grinding and disinfection technique, and simple holding tanks) to complex
combination electrochemical treatment devices (38).
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The aerospace industry has also been concerned with water supply and waste disposal,
and the demanding requirements for forced long term isolation have spurred intensive
efforts for the development of self-contained water supply and waste disposal systems.
Water is the heaviest single item required for man's survival (approximately 2500
g. per man per day) and soon becomes a limiting factor unless the water is reused
(76).  Thus the very feasibility of space exploration is dependent on water reuse.

Although most of the devices and processes discussed are presently too complicated
and too expensive for the average household,  it  is believed that a brief presentation
is warranted because this status may be greatly changed in the next ten to twenty
years.  The Ontario Research Foundation of Canada conducted a  study on the use
of some of these techniques for  the complete renovation and reuse of water in a
housing complex for one thousand persons.  The technical and economic study indicated
that such a  system would be feasible at the present time in water short isolated areas
or areas with very rough terrain (12). The United States Army is developing portable
water and waste management systems utilizing many of these techniques for use in a
mobile field hospital, and for use in advance military headquarters (37, 52).  It
must be remembered, however, that in such large housing complexes and in special
service units,  skilled personnel should be available at all times,  and that the same
economics would not prevail in  smaller units. However,  continued progress in
instrumentation and automatic control could make some of these  processes feasible
for the individual  home in the near future.

Applicable advanced treatment processes are discussed briefly below.   They are,
for convenience, grouped as change of phase processes, membrane processes,
electrolytic processes, and miscellaneous processes.  The processes are first
described and then discussed as to their feasibility for household use.  In the
following sections, the feasibility of using these techniques for household treatment,
either as a  total process  or as a means of improving the effluent from current treat-
ment units  (septic tanks and aerobic treatment devices) will be explored.

CHANGE OF PHASE PROCESSES

Liquid to Vapor Phase Changes

In distillation and evaporation processes, the separation of the water from the
impurities  is effected by  the change of phase from liquid to vapor and back to liquid
again.   Only those substances that  significantly vaporize at the pressure and tem-
perature of the distillation or evaporation apparatus undergo the same phase changes
and appear  as  significant pollutants in the product water.

Actually, evaporation and distillation are identical processes but they have slightly
different connotations  in practice.  In both cases, separation occurs due to the
changes in the relative composition of the liquid and vapor.  The rate at which the
liquid enters the vapor phase is dependent on the rate  of heat transfer, the rate at
which the vapor is removed, and the relative composition of the  liquid phase.
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 An air evaporation technique utilizing waste equipment heat has been studied by
 several investigators.  McNeil (56) investigated an evaporator system to dispose
 of urine aboard aircraft,  but the product was still corrosive (93),  Since then, other
 investigators have reported a considerably better product which could be rendered
 potable by varying degrees of auxiliary treatment with chemicals,  ion exchange,
 and activated carbon (76, 69).  In a 60-day manned test of a closed life support
 system an air evaporation unit successfully reclaimed water from urine and humidity
 condensate for a crew of four men (43).  For aerospace applications,  the major dis-
 advantages of the air evaporation system are the large surface areas (3.5 sq.
 ft. per man reported by Wallman and Barnett (93) required for sufficient heat
 transfer and the storage and disposal of the wicks used to provide  these large
 surface areas.

 For the household use of an air evaporation system, the problems of weight and
 storage space which were considered limiting for aerospace applications do not
 seem to be as significant. However, it must be remembered that  the systems
 considered for aerospace use were designed to process less than one gallon per
 man per day, whereas we are contemplating a use of more than sixty gallons per
 person each day.  Also, one of the major advantages of the system for spacecraft,
 the use of waste cabin and equipment heat which would otherwise be expelled to
 space,  is not possible in most homes.  Thus in the normal household, rather than
 3.5 square feet of wick area per person, approximately 220 square feet would be
 required and power would be used at  the rate of 338 watt-hours per pound of water
 produced ($56.50 per 1000 gal.)  (69). The water evaporated from raw wastes could
 be easily disposed of,  but would  require further treatment (e. g.  filtration, adsorption,
 sterilization) before any reuse because of possible microbial contamination and pro-
 bably odors.  A household system would additionally require a collection tank, a
 blower, and heating and condensing equipment.

 The wastes from this process should be solid and  easily handled though they would
 probably have a disagreeable odor.

 Distillation can  be carried out at various interdependent temperature and pressure
 combinations depending on the product desired.  Generally, low pressures are
 utilized to permit low temperatures and limit the decomposition and volatilization of
 organics.  In some units, the vapor is compressed without cooling so that the heat of
 vaporization can be more easily utilized in the distillation unit (vapor compression
 distillation). As with air evaporation, however, the product water still requires
 additional treatment before it is judged potable.   Membrane vapor diffusion is another
 distillation process in which a semi-permeable membrane is used to contain and
 separate the impure liquid from the vapor phase.  The heated  liquid diffuses through
the membrane and evaporates on the  outer surface.  An important advantage with
this system for aerospace use is  its operability at zero gravity.  With further mem-
brane improvements,  the membrane vapor diffusion system should be competitive
with vapor compression (48).  One method of additional treatment  is to catalytically
                                        68

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oxidize the vapor before it is condensed (6, 32).  The major disadvantages of the
distillation schemes for aerospace use are the high power and weight require-
ments (relatively speaking) and the danger of gas leaks in systems that operate
at other than ambient pressure (82).

A household system for distillation would  require a collection tank, a solids
separator (possibly included in the storage tank), and probably a final filtration,
adsorption unit which would render the effluent suitable for  all uses except drinking.
A vapor compression distillation system which conserves the heat of vaporization
required 35.3  watt hours per pound of water produced, (69) or $5.90 per thousand
gallons of water.  Steele (82) reported a power expenditure of 42,8 watt hours per
pound or $7.15 per thousand gallons.  Studies on a vapor compression unit designed
for household use by Dr. Hickman of Rochester Institute of Technology reported
operating costs of about $1.30 to $2. 00 per thousand gallons (10). The yield from
this unit which is limited to dilute wastes, is only about 1/3 to 1/2 the input.  Operation
of a distillation unit would depend on the close control of a number of variables and
would probably present household problems.  The waste from a distillation system
would be a dry sterile residue which could be easily handled or a concentrated
liquid.  There would also be the problem of disposing of the solids separated from
the waste water in the initial treatment step.  These could probably be  treated
similarly to septic tank solids.

Liquid-to-Solid Phase Changes

Pure water freezes at a higher temperature than a mixture of water and wastes.
Thus when the water-waste mixture is slowly cooled, pure  crystals of water form.
The problem is to separate the crystals of pure water from the waste mixture
entrapped in the crystal interstices.   Various techniques to obtain this  separation are
being investigated.  Multi-stage counter-current washing has been effective in
large scale operations, but at present, the technique appears uneconomical for
aerospace application (106, 82).  Zone refining is another variation of the freezing
process in which a column of water,  waste mixture is frozen; then a moveable
heating element forms a band of liquid which is moved along the column concentrating
impurities in the liquid phase  (76).  The process may be repeated for increased
purification.  Other freezing processes that have not been significantly developed
are column crystallization and counter current crystallization  (82).   The major
objections to these techniques are the low percentage of water recovered and the
problems of separating the ice from the water-waste mixture.

In addition to cooling equipment the processes involving solid liquid separation
will require elaborate separation equipment.  Work with freezing techniques involving
liquid solid separation for waste water renovation has been relatively unsuccessful
due to the difficulty of separating the pure ice from the waste water.  Studies at the
Robert A. Taft Sanitary Water Research Center on freezing techniques for the
renovation of waste water were halted because of the relatively high process costs.
Besides the high costs, the freezing techniques require constant control and super-
vision to insure quality.  Most homes could not supply this  supervision.


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  Solid-to-Vapor Phase Changes

  At low temperatures and pressures, water can be changed directly from a solid to
  a vapor without passing through the liquid phase.  This sublimation or freeze
  drying process is rapidly becoming an important food preservation process.  The
  low temperatures limit organic decomposition and volatilization to insure a relatively
  high quality product.  Virtually all the water is recoverable,  and the waste materials
  remain in the solid state, thus facilitating waste handling and reducing leakage pro-
 blems  (82).

 The processes involving vapor sublimation from the solid ice will require vacuum
 apparatus and vapor condensing equipment.

 The system involving the solid to vapor phase change has demonstrated the capability
 of producing a good quality water.  Energy equal to the energy difference between the
 solid and liquid must be removed from the waste water to produce ice,  and then just
 enough energy must be added to change the solid to a vapor from which the water is
 then condensed.  The household cost of these processes is estimated to be at least
 (assuming 80% power recovery) $10.90 per thousand gal.  and would yield water
 suitable for any use but drinking.

 The waste residues from the process could be easily handled  and stored until cen-
 trally collected.

 MEMBRANE PROCESSES
 Membrane processes require no phase change; they depend on membrane selectivity
 to separate the water from the  wastes.  The membrane acts as a filter to exclude
 all particles larger than its pores,  and as a diffusion medium which governs the rate
 at which soluble substances pass through it.  By altering the structure and com-
 position of the membrane the substances passed by the membrane can be selectively
 controlled.  The membrane mechanically restricts the passage of any substance and
 a force is necessary to drive a substance through the membrane.  Additional energy
 is required to overcome the concentration dependent osmotic  pressure.  Mechanical,
 electrical, thermal, and concentration gradients have been successfully used as the
 driving force in various applications.  One major problem with the membrane
 purification process is that the practical limit to which the wastes can be concentrated
 is much lower than the concentration at which the wastes can  be easily handled and
 disposed of.  However, membrane processes theoretically require less  energy than
 the phase change processes,  and much water treatment research is directed toward
 solving or by-passing the problem areas of membrane  technology.  Spectacular
 results  are also being predicted for the application of membranes in many different
fields:   medical technology (artificial organs), photographic equipment,  batteries,
 etc.  (57). The concentrated efforts in these varied fields could hasten the discovery
 of solutions to membrane problems.
                                       70

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Reverse Osmosis
Originally, ultrafiltration was used to denote microstraining and reverse osmosis
was used for the process utilizing activated diffusion.  Ultrafiltration membranes are
rapidly clogged, however, and there is a tendency to use reverse osmosis membranes
for ultrafiltration.  As a result, the two terms are sometimes used interchangeably
to describe the forced solvent flow through a  membrane from a high solute concentra-
tion to a low concentration in opposition to the natural concentration gradient.  Con-
siderable research  is being conducted to perfect reverse osmosis techniques for
industrial processing and for treatment of various industrial and municipal waste
streams (65).

Although reverse osmosis has the capability of removing non-ionic material as well
as ionic species,  probably its first household usage will be for the removal of ionic
species.  A household unit for demineralizing water and which operates on the water
line pressure has already been developed and is  projected to be sold for approxi-
mately $125 and to treat the water at a cost of about $8.20 per thousand gallons
(63).  One manufacturer has begun promotion of  its version of a small reverse
osmosis system to remove taste, odor, color and sediment.  Costs are estimated
at seven cents per gallon ($70.00 per 1000 gal. >.  The cost of treating more con-
centrated wastes would be significantly higher because of the higher osmotic pres-
sure of the wastes and the additional equipment that would be required. The wastes
from a reverse osmosis treatment unit would be a concentrated liquid with pro-
perties dependent on the wastes being processed. The product water could be used
for all household purposes except drinking.

Electrodialysis
Electrodialysis is a membrane technique in which the driving force is electrical
potential.  Membranes can be prepared to pass only cations or anions, and a solution
placed between an anion permeable membrane and a cation permeable membrane
and subjected to an electrical potential can be effectively depleted of ionic solutes.
However,  nonionic species are not affected.  The main disadvantages of electro-
dialysis are the additional purification processes that must be used to remove
uncharged particles and particles too large to pass through the membrane (81).  A
variation of electrodialysis,  the osmionic process, utilizes ion permeable membranes
to produce electricity for electrodialysis. Ions flow from a concentrated salt
solution to dilute solutions through cation and anion selective membranes, creating
an electrical potential between the dilute solutions which is then used for
conventional electrodialysis.  This process requires large quantities of the  salt
solutions,  and like electrodialysis produces dilute wastes, and a product that still
requires additional treatment (83,  11).

Thermo-osmosis utilizes a temperature gradient to drive the water through the
membrane.  When solutions of different temperatures are placed on  opposite sides of
                                        71

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 a semi-permeable membrane, there is usually some transport of water from one
 solution to the other.  The rate of water transport is determined by the temperature
 difference and the thermal characteristics of the membrane itself (93).

 Electrodialysis or related techniques could only be a part of a water treatment scheme
 since they remove only ionic species.  The power  required for such a system is a
 function of the quantity of ions in solution.  The cost of power has been estimated
 at $8.50 per thousand gallons for the electrodialysis of treated urine and at approx-
 imately $1.00 per thousand gallons (extrapolation of data by Smith,  (77) for the
 effluent of a  secondary treatment plant.  The wastes to be disposed of will be con-
 centrated salt solutions.

 ELECTROLYTIC PROCESSES
 Electrolytic waste treatment plants attracted a great deal of interest in the late
 1800's and early 1900's.  The most famous process was the Landreth method in
 which the waste water  was heavily dosed with lime and then subjected a direct
 electrical current.   The effluent was described as  clear, odorless and non-putrescent.
 There was some question as to whether the same degree of treatment could be ob-
 tained with the concentrated lime dosage alone (58).

 The Pennsalt Chemical Corporation, under contract to the Public Health Service,
 completed an extensive study of electrochemical treatment  of secondary treatment
 effluent.  This study concluded that the system was uneconomical (a cost in a 10
 mgd plant of  $.90 to 2.40 per 1000 gal.) because of the low conductivity of the
 water.

 The electrolytic process is being investigated for treatment of raw sewage by
 chemical coagulation of suspended solid material and chemical treatment of the
 liquid in Norway and Italy. The  sewage and  sea water are mixed and eleetrolyti-
 cally decomposed.  As hydrogen is released, the increasing hydroxyl concentra-
 tion permits  stable formation of  practically insoluble magnesium ammonium
 phosphate and calcium phosphate precipitates and the  flocculentprecipitate of
 magnesium hydroxide.  The magnesium hydroxide  floes occlude other suspended
 solids, and the floes are floated  to the surface by the hydrogen gas formed.  The
 oxygen and chlorine released at the cathode also help to disinfect the product water
 (35).

 The equipment required for this  electrolytic treatment would include a rectifier to
 supply direct current power, electrodes, a waste collection system, and a sludge
 collection and disposal system.  In an attempt to avoid the high power costs for water
 of low conductivity, the idea of adding chemicals to approximate the conditions
used in the Norwegian and Italian studies was briefly investigated.  However, the
 cost of chemical addition would again raise the operating cost to at least the $2.00
per thousand  gallons of waste treated as quoted for the low  salt domestic wastes.
 The effluent from the pilot plants constructed in Norway (35) was apparently high
                                       72

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quality with a very low number of bacteria.  After filtration the effluent could
possibly be used for all household purposes except drinking.  The sludge produced
could probably be handled similarly to septic tank solids.

The U. S. Navy is testing a device which mechanically separates and incinerates
waste solids, which are transported by a seawater flush, and electrolytically treats
the remaining liquid.  Electrolysis produces minute bubbles of hydrogen, oxygen,
and chlorine which float suspended solids to the surface where they are skimmed off.
The chlorine and oxygen additionally act as oxidants and are effective  in the control
of disease causing microorganisms (44).  This unit has been extensively tested and
when not plagued by minor mechanical difficulties has bettered effluent standards of
1000 coliform/100 ml, 50 ppm BOD, and 150 ppm suspended solids.

An electrolytic method is also being investigated by the space agency as one of the
steps in the processing of urine for reuse.  This method utilizes an electrochemical
oxidation process to decompose urea and other organics into hydrogen, nitrogen, and
carbon dioxide.   It is expected that a combination of this method with electrodialysis
can produce acceptable product water from urine at a total operating cost of about
190 watt-hours per pound (approximately $31.70 per thousand gallons).  The equip-
ment would also be relatively expensive (5).

In another electrolytic process proposed for an aerospace system, the water and
waste mixture is electrolytically decomposed to hydrogen at the cathode and oxygen
at the anode.  When the oxygen and hydrogen are recombined, pure water is formed.
When the two gases are combined by combustion, the high temperatures attained are
sufficient to completely oxidize any volatile organics.  Another approach is to
recombine the oxygen and hydrogen in a fuel cell to obtain useable electrical power,
which would partially offset the power required for electrolysis, (4, 6).

Such an electrolysis system would require a waste collection system, a source of
direct current, and a device to recombine the hydrogen and oxygen to produce water.
A fuel cell could be used  to recombine the hydrogen and oxygen and recover some
of the power, or if the hydrogen and oxygen were recombined by combustion, heat
recovery could be practiced to conserve power.  Suitable equipment is not readily
available but operating costs can be roughly estimated (assuming 75% power recovery)
to be approximately $70.00 per thousand gallons.  The recovered water could be
used for all purposes and the waste would be relatively easy to handle; but the ex-
cessive power requirements and present inefficiencies in power recovery apparatus
should make further analysis of this system unnecessary in this study.

MISCELLANEOUS PROCESSES
Oxidation

Oxidation is the process which currently dominates the domestic waste treatment
field.  Biological oxidation  is used in sewage treatment almost exclusively and chlorine
chemical oxidation is the most popular method of water disinfection.   Organic wastes
                                        73

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 are oxidized to carbon dioxide,  water, and oxides of nitrogen and other elements.
 New techniques of inducing oxidation and new or less expensive oxidants may permit
 more effective water and waste treatment in the future.  A comprehensive listing of
 oxidants for waste treatment is included in the series of studies for Advanced Waste
 Treatment by the Federal Water Pollution Control Administration (1).   One company
 has reportedly developed a system utilizing gamma radiation to  induce oxidation for
 a home sewage treatment unit (Chemical and Engineering News, April 21, 1969).
 We have no additional information on this unit, but the AWTR-19 Summary Report
 (2) estimated that in large installations the cost would be least $0.50 per 1000 gal.

 At high temperatures and pressures organic material in a liquid suspension can be
 rapidly oxidized by oxygen in a pressurized apparatus.  This technique, wet
 oxidation, is gaining acceptance for the treatment of municipal sewage sludges  and
 is being tested as a method of shipboard sewage treatment (38,  Marine Engineering
 Log, 1967).  The process has also been tested for aerospace use in the treatment
 of waste solids collected from other water purification systems and for the
 recovery of water in feces (98).

 Simple incineration has been successfully used to oxidize human wastes in isolated
 locations and has  been suggested for use on watercraft.  However, an air pollution
 problem could be  expected if the use of incineration became common.  The problem
 may not,  however, be much more acute than the air pollution from individual heating
 units.

 For the household, the oxidation techniques that seem most likely to be used  in the
 near future are the oxidation of waste solids by incineration and chemical oxidation
 for disinfection of treated water.  Incinerator toilets capable of disposing the sanitary
 wastes from an eight member family are commercially available; some can even
 accommodate the  rinsing of diapers. The incinerator toilets can effectively eliminate
 water pollution problems but introduce the possible danger of air pollution.   Using
 manufacturers' data on fuel and power consumption and assuming normal usage,
 the operation of the incinerator toilet would average slightly more than $17 per
 person per year and cost $400 to $600 for purchase and installation.

 The use of the wet oxidation technique to treat wastes of the nature and volume  of
 household wastes would cost about $40.00 per thousand gallons.  The effluent would be
 stable but not fit for any reuse without extensive additional treatment.

 Chemicals have been widely used for disinfection and many different types of equip-
 ment are available to dispense disinfecting chemicals.   Chlorinators, for example,
 can be purchased for $150 to $600 and operated for approximately $0. 08 per
thousand gallons of water treated.
                                        74

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Chemical-Mechanical Removal of Contaminants

Many of the mechanical means of water and waste treatment such as sedimentation,
filtration, and adsorption can be aided by the addition of proper chemicals.  Lime
and soda ash are used to precipitate the ions  causing hardness in water.  Aluminum
and iron salts  are used to coagulate suspended  and colloidal solids prior to sedimen-
tation or filtration.  Still other chemicals, such as  activated  silica and various
polyelectrolytes, are used to aid coagulation  by stimulating the formation of floe
particles. Activated carbon is commonly used in the removal of taste, odor, and
color by adsorption.  The series of publications by the Taft Sanitary Engineering
Center on advanced waste treatment research provides an extensive discussion on the
use of these chemical-mechanical techniques in the treatment of waste water.

Chemical coagulation and activated  carbon adsorption were  the treatments chosen
in a study for the U. S. Army on the renovation and reuse of kitchen, laundry and
shower wastewaters for all purposes except drinking and food preparation (37).

A system utilizing coagulation, sedimentation,  filtration,  and carbon adsorption has
been developed to treat the waste water from coin operated  laundries,  (85).  A
similar system installed in the Virgin Islands is reportedly treating the laundry
waste water for reuse.

New innovations are also being applied in simple filtration.  Multimedia filter beds
have been developed to achieve longer filter life and more efficient utilization of
the filter depth.  New filter systems have been developed to remove even bacterial
sized particles.  A study of water reclamation techniques for aerospace use showed
a multifilter system  (particulate removal,  carbon adsorption,  and ion exchange) to
be most suitable for  reclamation of the wash waters and dehumidification condensate
on space voyages of intermediate lengths (94).

Most of the chemical-mechanical contaminant removal techniques are relatively
inexpensive when applied on the scale of community  water treatment plants, but
become increasingly costly in small installations because of the chemical handling
costs and the supervision required.  To date, few automatically controlled systems
have been marketed for household use.  Filtration is practiced in rural areas to
treat water supplies  of uncertain quality for household use.  Slow sand filtration
and filtration through commercially available pressure filters of sand, carbon and
prefabricated  cartridges were evaluated in a study at the  Ohio Agricultural Experi-
ment Station (42).  A slow sand filtration apparatus  could be supplied for approx-
imately $120. 00 and  could be operated for l£ to 2£ per thousand  gallons (not
including the cost of  pumping water from the filter).  Pressure sand filters require
less space than slow sand filters but are more expensive  to operate and produce a
lower quality effluent.   Pressure sand filters are sold for about $120. 00  and process
the water at approximately 10j({ per thousand  gallons. Cartridge filters are avail-
able for many  filtration tasks.  Swimming pool filters including pump are available
at $130.00 and filter gross solids at a cost of approximately $. 07 per thousand
gallons.  Other cartridge filters are available  to remove  various solids down to
0.5 microns in size.

                                        75

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  Collection and Storage

  Collection and storage of wastes until a disposal site is available has been practiced
  by airlines and watercraft for years.  The wastes are merely stored until they can be
  disposed of.  Obviously,  as the volume to be disposed decreases, the time between
  dumping increases and the economy is greater.  One commercial company now offers
  a water closet which recycles disinfected flushing water and reportedly collects and
  stores wastes from 80 to 100 uses when primed with only four gallons of water (38).
  Systems for collection and storage of waste  are widely used for boats,  travel trailers,
  and long distance trains, busses, and aircraft. Removal and disposal  of the collected
  wastes is a nuisance most people would not tolerate in their homes.  Any system for
 the home should therefore be designed for direct discharge to sewer or septic tank.
 Such a recycle toilet with  a discharge pump can be purchased for approximately
 $280.00 and can be operated for about $. 01 per flush including disinfection (a yearly
 cost  of $18 to $19 per person).  Laboratory tests indicated that the chemical used for
 disinfection would not hinder  either anaerobic or aerobic treatment of the collected
 wastes.

 Solvent Extraction

 Solvent extraction is a process in which the water,  but not the contaminants,  is
 dissolved in a solvent. The water-solvent solution is then separated from the
 mixture and separated from each other by distillation (103). Solvent extraction
 does  not appear suitable for adaptation to household use.  The method requires an
 extraction column which must be maintained at the  proper temperature, a tank in
 which to separate the water-solvent solution from the waste mixture, and distillation
 apparatus to remove the water and recover the solvent.  Also,  pilot plant installations
 have  experienced difficulty in completely removing the solvent after treatment.
 Preliminary cost estimates for the solvent extraction technique in large installations
 approach $. 50 per thousand gallons.  Household operation would  be  much more
 costly.

 Solid  Hydrate Formation

 Certain hydrocarbons will form addition compounds with water which are called
 hydrates.  The hydrates are solids that can be separated from the water-waste
 mixture by filtration.  This process thus depends on a fine straining process
 following the hydrate formation.  As in the freezing process temperature and pres-
 sure control and separation of the solid phase from the  mother liquid pose significant
 problems which are being studied at industrial and institutional laboratories  (76,  62).

 The hydrate technique of water purification involves most of the same problems
 encountered in the conventional freezing processes.  In addition,  provisions  must be
 made to recover and recycle the hydrocarbon after it has been removed from the
 water.  Temperature and pressure control are also essential in the hydrate forma-
tion.  Operating costs would probably be at least as high as those of the freezing
techniques.
                                        76

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Maceration-Disinfection
Maceration-disinfection is a technique with little value for the prevention of pollution
by treatment of wastes,  and its capability for disease  prevention through disinfection
is often questionable.  Maceration disinfection has been used to treat wastes from
watercraft by grinding the wastes to small sizes and adding a disinfectant to kill
bacteria.   The  process has been only partially successful in that the grinding is not
always complete and the disinfection is not completely effective.  In addition, the
treatment does not remove or effectively change any of the polluting substances (38).
                                             77

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                                     VI

     ENGINEERING STUDY AND EVALUATION OF PROCESSES FOR WATER
                   CONSERVATION AND WASTE TREATMENT
This section explores the practicality of the various combinations of current water
and waste treatment techniques which appear promising for the flow reduction or
treatment of household waste waters. Rather than making a detailed examination
of all the possible systems, the large number of treatment or flow reduction tech-
niques was first reduced by a qualitative evaluation.  Then a technique for the com-
prehensive analysis and evaluation of household water and waste systems is developed
and applied to some of the treatment schemes already discussed.

Tables XI and XII list the various means discussed for reducing water usage and the
various techniques for treating the wastes produced.  There are hundreds of different
ways in which the water conserving devices and the various treatment techniques
could be integrated into a household water and waste handling system.  To facilitate
the screening of all the possible systems for water and waste handling, the problems
associated with possible changes in the present water and waste water systems were
analyzed.  The typical home plumbing system (figure 2),  the uses made of water at
each of the supply points (table n), and the pollutants introduced at each drain
(table VII) were evaluated to determine a relative order for the quality of water
required at each supply point (table XHI).  A comparison was then made of the quality
of the various effluent streams and the quality required at the supply points so that
the treatment required for reuse could be estimated.

Figure 9 shows the whole realm of reuse possibilities for household water-waste
systems.  Technically,  the reuse of waste water from any appliance or drain is
possible, though possibly not economically or aesthetically feasible,  at any supply
point or for any purpose if it is given suitable treatment and a suitable piping system.
In the figure, we have used explicit criteria for the decision as to the feasibility of
using waste waters from the various sources at the various points of use.  For
example, water from the bathtub or shower drain for reuse in the washing machine
is coded S  , the S meaning suitable with a minor degree  of physical and chemical
treatment, and the subscript A indicating that there may  be aesthetic grounds for not
using this reuse combination.

Assumptions used throughout this evaluation section were (1) that reclaimed water
would not be used for drinking and cooking,  (2) that water from any outlet may
occasionally be ingested, and (3) that homeowner acceptance of dirty looking water
will be low even though it might be suitable for its intended use.  Thus, the water
                                        78

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                    Table XI, Water Savings Plumbing Devices
                            Water
                            Savings
Estimated Installation
       Costs
  Hardware Device
  1.   Limiting Flow Valves
      for Shower
  2.   Limiting Flow Valves
      for Lavatory
  3.   Limiting Flow Valves
      for Kitchen Sink
  4.   Aerator for Lavatory
      and Kitchen Sink

  5.   Batc'h-type Flush
      Valve (1) for Water
      Closet

  6.   Batch-type Flush
      Valves (2) for Water
      Closet

  7.   Urinal with Batch-
      Type Flush Valve
  8.  Shallow Trap Water
     Closet

  9.  Dual Cycle Water
     Closet

10.  Vacuum Flush Toilet
      (for 100 Homes)

11.  Vacuum Flush Toilet
     (for Single Homes)     22.5
12.  Washing Machine with
     Level Control
13.  Recycle Toilets
gpcd +
6
0.5
0.5
0.5
7.5
15.5
7
7.5
17.5
22.5
22.5
1.2
24.7
Matl.
$
35
45
45
2
75
120
150
80
100
-
-
35
300
Labor
$
15
23
23
0
30
38
25
30
30
„
-
0
25
Total
$
50
68
68
2
105
158
175
110
130
295
1520
35
325
 +  gal/capita-day (gal/person/day)
                                        79

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                                Table XII.  Techniques For Treatment Of Waste Waters
                              Estimated Average Costs (from data in the literature)
oo
o
Technique
Anaerobic Treatment
Aerobic Treatment
Air Evaporation
Distillation
Freezing
Electrodialysis
Reverse Osmosis
Electrolytic Treatment
Electrolysis
Incinerator Toilets
Wet Oxidation
Disinfection
Gravity Sand Filtration
Pressure Sand Filtration
Cartridge Filtration
Solvent Extraction
Equipment
& Installa-
tion Cost
$1100
1200
700*
1000
1000*
150
150
500 *
300*
500
1000*
200
120
120
130
____
Operating Costs per
Thousand Gallons Not
Including Amortization
Less than $0. 01
$ 0.60
56.00
4.00
8.00
1.50
8.00
2.00
70.00
17. 00 per person/yr.
40.00
0.05
0.02
0.10
0.10
10.00
                 Comment
Most common method of waste disposal

Treatment of all Wastes
Cost for mineral removal only

Mineral removal only.
Cost for mineral removal only
                                                                         Usually used for concentrated wastes
                                                                         Unsuitable
    *household sized systems not commercially available.

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00
   Technique
   Gas Hydrate Formation
   Maceration Disinfection
   Coagulation, filtration
   Carbon filtration
   adsorption
                                                 Table XII.  (Cont'd)
                              Estimated Average Costs (from data in the literature)
Equipment       Operating Costs per
& tostalla-       Thousand Gallons Not
tion Cost         Including Amortization
$	            $ 10.00
 110               50.00 per person/yr.
 600 *              3.30

 600*              1.60
                Comment
Unsuitable
Unsuitable
Treatment of all wastes

Cost for treatment of non sanitary wastes only
   *household sized systems not commercially available.

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           Table xm.  Relative Levels Of Water Quality Requirements

Order of Water Quality Requirements (Highest Quality First)
1.  Drinking and Cooking
2.  Dishwashing
3.  Bathing
4.  Clothes Washing
5.  Household Cleaning and General Purpose
6.  Toilet Flushing

Order of Supply  Points as Related to Water Quality Requirements
1.  Kitchen and Bathroom Sinks, Hot Water  Heater
2.  Dishwasher
3.  Shower, Bathtub, Set Tub
4.  Washing Machine
5.  Outdoor Faucet, House Heating System
6.  Toilet Bowl
                                       82

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Potential Household  Water Sources













































rH
ft
ft

co

=HA
XHA
XHA
^
SDHA
SA
SDHA
SDE
SA

4O
A

f^
O

^
d)
^
o
{— t
CO
^A
XHA
XHA
XHA
SDW
SA
TT
SDE
SA







•P
0
rH
•H
o
EH
XHA
XHA
XHA
V
XHA
XHA
XHA
XE
XEA












Point of Water Use
Sink (Kitchen)
Sink (Bathroom)
Water Heater
Dishwasher
Shower or Bath
Laundry
Outdoor Faucet
House Heating Sys.
TOllet
Treatment Required Before  Use:
Y  No treatment required
D  Disinfection
S  Minor dhemical and physical
     treatment
X  Complete renovation
                                  Reasons  for Treatment:
                                  H  Health
                                  E  Engineering
                                  A  Aesthetic
    Figure 9.  The Reuse Potential of Household Waste Water
                           83

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for any reuse must be biologically safe and contain no chemical substances considered
dangerous to health when accidentally consumed.  Also the water supplied to any
point in the  system where drinking or cooking water is commonly drawn must be
connected to a drinking water supply. For example, both hot and cold water supplied
to the bathroom and kitchen sinks must be taken from a safe drinking water supply.

Present practices would dictate that only two classes of water could be used in the
household.  Most people have at some time obtained water for drinking from every
supply point in the house (bathtub,  shower, laundry, outside faucet) except from
the water closet; and, therefore,  if present practices are to continue, the only pur-
pose for which non-potable water could be used would be toilet flushing.  Present
practices could be changed, however.  People  could be educated not to use all the
supply points for drinking.  Dual quality water systems  have been used in some
areas for years. In sections of the West brackish water systems are used for many
non-critical purposes to conserve a limited fresh water supply.  Many ships use a
seawater system for toilet flushing,  deckwashing, and fire fighting.  To encourage
the safe use of multiple quality water systems, a reminder of the lower quality,
such as color, odor,  or taste,  could be added to the water; in addition the outlets
themselves  could be colored or shaped differently.  Some people may point out that
small children may not recognize these danger signals;  but this danger would be no
greater than in the present situation in which the water supply most accessible to
small children is in the toilet.

PRELIMINARY ECONOMIC ANALYSIS
After review of the problems and the requirements that must be met, the various
systems were then subjected to a preliminary economic evaluation.  Most people
are  interested in pollution abatement and are willing to encourage the spending of
government money in the pollution abatement program.  However,  they are much less
willing to spend their own money for a private  pollution  control measure when their
neighbors are not also compelled to do so.  Thus, few homeowners are likely to put
any  device into their homes that is not specifically required by law, unless it can be
shown that the device will cost less (or at least not more) and will require very little,
if any, more maintenance than their present system.

For this reason, all the treatment techniques considered in the previous sections
were examined from  an order-of-magnitude cost viewpoint to eliminate those schemes
that would be economically unacceptable to the average homeowner.  Each proposed
treatment or waste reduction system is compared to the cost of the present water and
sewerage system at homes with central water and sewerage and at homes with septic
tank systems on good, fair, or poor soils.

The  cost figures were taken from many sources including reports from the Office
of Saline Water, the Public Health Service and the Federal Water Pollution Control
Administration.  All  assumptions were slanted toward making the processes less
expensive, so that no process would be unnecessarily eliminated.
                                        84

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The general assumptions used throughout the comparison were:

    a.   Each system will be installed in an "average" home as described on
        page 8 with a four member family having an "average" water use of 255
        gallons per day distributed as follows:

            27 gal.  kitchen & drinking

            88 gal.  bathing & hygiene

            40 gal.  laundry & cleaning

            100 gal. toilet flushing

    b.   Electrical energy - $0.02/KWH

    c.   Fuel oil - $0.15 per gal.

    d.   Water rate - $0.42 per 1000 gal.

    e.   Sewerage rate - $0.44 per 1000 gal.

    f.   Cost of septic tank soil absorption - as discussed on page 42.

The results of the cost comparison are shown in table IVA included in the appendix.
In this table, column (1) represents the annual per person cost of purchasing, install-
ing, operating, and maintaining the waste treatment or flow reduction system.
Column (2) is the average annual cost of the water used per person,  column (3) is
the average annual per person cost of disposing of the waste water; and column (4)
is the total yearly cost of water and the disposal of waste water for one person.
Column (5) compares the total cost of the system being considered with the cost of
the conventional systems now being used. (Item 1).

Each new system evaluated is considered for installation in comparison with four
generalized conventional systems:  (a) in areas having sewer service and average
water costs, (b) in areas having soil absorption systems in good soil,  (c) in areas
having soil absorption systems with fair soil,  and (d) in areas having soil absorption
systems with poor soil,  (soil classifications according to Thomas (87)). In addition
(e) shows effect of a low water rate ($0.20/1000 gal.) and (f) shows the effect of a
very high water rate  ($1.50/1000 gal.) for the  system with sewers.

This brief economic analysis provided many enlightening comparisons and per-
mitted recommendations for the further  investigation or the elimination of various
schemes.  The information from the cost comparison table is summarized below:

    1.   Reduction of water usage appears to be economically the most feasible means
        of reducing waste flow from the home.
                                       85

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 2.  Flow control faucets are of marginal value when replacing workable faucets,
     but are definitely warranted for new homes and for necessary replacements.
     Faucet aerators would apparently be a useful addition to all faucets for
     convenience as well as water savings.
 3.  Flow control showers are an inexpensive means of economically saving con-
     siderable quantities of water.
 4.  The use of pressure flush valves to reduce water flow does not appear as
     advantageous as the redesign of the toilet bowl to allow adequate flushing
     with less water.
     The pressure flush valve could be advantageously used with the redesigned
     toilet bowl.  Siphons, as used in the English water closets, would also
     provide better volume control than the system presently used in the United
     States.
 5.  The vacuum flush toilet for the individual home is too expensive because of
     the  high cost of the accompanying equipment when used for single homes.  As
     mentioned on page 64 the use of the vacuum flush system for groups of
     dwellings or multiple dwelling units was considered to be outside the scope
     of this study.
 6.  The major  economic disadvantage of the recycle toilets is the high cost of
     the  chemical used for disinfecting the recycled flush water.  Development of
     a suitable,  lower cost disinfectant could make their use much more practical.
     There could be a problem with acceptance of reused flush water in the home,
     but  this objection does not appear insurmountable.

 7.  Incinerator toilets are excessively costly to operate and maintain for
     family use. For certain applications, such as weekend cabins which are
     used sporadically, the incinerator may be the most economical system, but for
     normal  continuous use, the incinerator toilet can not economically compete
     with conventional systems.

 8.  The analysis of the system to reuse wash waters for toilet flushing reveals
     several very significant facts.  The treatment and the quality standards
     required for flushing water are minimal and the costs are thus relatively
     low in comparison with those for any other reuse. Yet this treatment and
     reuse is economical only in fair and poor soil areas.

 9.  The additional treatment of the non sanitary waste waters by distillation,
     reverse osmosis,carbon adsorption, or a multifilter system for use as
     laundry and bathing water as well as toilet flushing does not appear econo-
     mically feasible.

10.  The treatment of all waste waters by distillation and reuse for all purposes
     but drinking is also economically unattractive.
                                     86

-------
    11. Aerobic treatment is competitive with anaerobic systems in poor soil areas.
        In such poor soil areas, some reuse may also be warranted.

    12. Electrolytic treatment for disposal is  not economical for most areas because
        of the low conductivity of the  water.

Based on these observations from table FVA, the systems that warrant further
discussion are the various means of restricting water usage, reuse of wash waters
for toilet flushing, and the use of aerobic treatment systems in poor soil areas
with the possibility of treating and reusing portions of the aerobic effluent.

ADDITIONAL ANALYSIS OF PROPOSED SYSTEMS

From the  information available in the  literature and the limited  information supplied
by the equipment manufacturers there is not enough actual data to perform an accurate
and detailed examination for most of the proposed water reduction or waste treatment
schemes.   We have, however, developed criteria suitable for an actual detailed
evaluation and have presented examples pertinent to this discussion.

Criteria For A Semi-Quantitative System Evaluation

Definite evaluation criteria were established to facilitate an objective comparison
of the possible flow reduction and treatment schemes.  The criteria chosen and their
relative values are given in the following table.  The  reasons for this selection are
then discussed.

    Criteria                                    Weighted Value (%)

1.  Initial Cost                                        20

2.  Operating Cost                                     20

3.  Reduction in Waste Volume                         20

4.  Effluent Quality                                    10

5.  Operating Attention                                 10

6.  Aesthetics                                         10

7.  Safety                                              5
8.  Compatibility with home plumbing                   5

All the evaluation criteria can be grouped under cost, utility, or household
acceptability. These main groups are further  broken down to make evaluation easier.
Cost is represented  by initial cost and operating cost; utility is  represented by
reduction in waste volume and effluent quality;  household acceptability is represented
by operating attention required, aesthetic factors, safety,  and compatibility with
home plumbing. Thus,  of the total evaluation 40% is  based on costs,  30% on utility,
and 30% on household acceptability.
                                        87

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Cost, utility,  and household acceptability are all essential for the success of a
household waste treatment or volume reduction system, but cost was given the greatest
weight because of its tendency to override the others.  For example, excessive costs
would readily cause a system of great utility and desirability to be rejected, while
low costs could induce acceptance  of systems with some undesirable features and of
limited utility.

Under the heading of cost, initial cost and operating cost were given equal weight.
Reduction of waste volume was considered of somewhat greater value than effluent
quality because all cases produce some waste,  requiring treatment either at the source
or in a municipal system, and reduced volume allows greater efficiency in this treat-
ment. Safety is the most important factor for household consideration, but we are
assuming that all systems considered will provide adequate  safeguards against
disease or accidents. Thus, in this discussion safety is considered secondary to
operating attention and aesthetic factors. Compatibility with present systems is
also given a lesser value, since it is already a factor in the initial cost and is a
lesser problem in new installation where such systems are most likely to be
accepted.

     !•   Initial Cost - Initial cost is meant to include all expenses of installing
         and preparing a system of waste volume reduction or waste treatment for
         reuse.  This initial cost will include the purchase cost of equipment
         required and installation costs, including the cost of alterations in the
         present system needed to allow the installation and use.  Costs should
         not include items normally in the home.  Items which are normally included
         in a household  system but are not required with the proposed system should
         be counted as savings.  The initial cost rating of systems will be determined
         as follows:

         , ... , „  .  „ ,.      Initial Cost of Present System  __ ftA
         Initial Cost Bating  = _ ... ,  _,—^  . _ 	'   ,    X20
                         &    Initial Cost of Proposed System

     2.   Operating Cost - Operating cost includes all direct material,  power,
         and labor expenses incurred in the operation of the proposed system.
         Operating cost  does not include a cost for the duties which would normally
         be performed by the homeowner; these are accounted for under the heading
         of "Operating Attention".  Operating costs will include the cost of water
         used and the cost of disposing of any waste water.


         _    ,.    ,,.„..      Present Operating Cost	
         Operating Cost Rating =	~—v:   ; JV  	•—	   x 20
          F      &           &    Operating Cost of Proposed System
                                          88

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3.  Reduction in Waste Volume - Reduction in waste volume is very simply
    computed as the decrease in water requirements,  since normally all water
    taken in (not including water for irrigation) is eventually discarded to the
    waste disposal system.


    Reduction in Waste Volume Rating = (1.0 - Water used in proposed system
                                               water used in normal system  '

4.  Effluent Quality - The quality of the  effluent which is discarded as waste
    from the system is very important in that it accounts for possible difficulties
    of transporting the waste to the final treatment center (including problems
    with corrosion,  solids,  viscosity, etc.), and the difficulty of treating this
    final waste at  the treatment center.

    Definite values for these parameters are not readily available and will
    depend on the  system and the type of final treatment proposed.  Thus  each
    system must be individually considered.  For the examples presented the
    systems are given a subjective rating from 1 to 10 which is then discussed.

5.  Operating Attention - Operating attention refers to the time that the home-
    owner must spend in the normal operation and maintenance of the system for
    reducing waste volumes or treating wastes.  It does not include main-
    tenance work that is normally hired  through service firms or contractors.
    Such maintenance is included in operating cost.


    _,,..-          ...  ,.      Hours per  yr with present system
    Rating for Operating Attention  = —	^—J	177—K	-p—;— X 10
                                    Hours per yr with proposed system

6.  Aesthetics - Aesthetics refers to the personal reaction of household members
    to the use of the proposed technique  for treating wastes or reducing the
    volume of waste water discharged.  This also is a rather  subjective and
    individually variable rating which will be discussed for each  of the examples.

7.  Safety - Safety is the term included as a measure of possible health hazards
    associated with the presence and use of the various devices for treating
    wastes or reducing the volume of wastes produced.  All devices considered
    should be designed to eliminate unusual safely hazards, but the remote
    possibility of a disease  or accident will of course exist.  This rating  will
    therefore be an evaluation of the risk involved. The rating of each process
    assigned will be individually discussed,
8.  Compatibility  With  Present Designs  - This term refers mainly to problems
    that may arise from changes required in the way homes and utilities are
    currently designed and built.  K does not refer to simple rearrangements in
    plumbing fixtures since these are included as part of the initial cost for
    installation.  It does refer to such things as changes in the requirements for
    power, sewage lines, and home or lot sizes.  Each process will be given
    a subjective rating from 1 to 5.

                                    89

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Evaluation Examples
This section presents some brief examples (using the remaining waste reduction and
treatment schemes) of the evaluation process and illustrates the kinds of problems
that need to be considered. Also included are two comparative examples of a dis-
tillation process that had been previously eliminated because of high costs. In
these examples, the water reduction or waste treatment device is compared with the
device it would replace in the present household.  Faucets with aerators are com-
pared to faucets without aerators, shallow trap toilets are compared with the normal
toilet, etc.  In each case a schematic diagram is used to represent the water use in the
household.  Unless stated otherwise, the items in these examples are considered
to be installed in older homes with municipal water and sewerage service. In homes
with private waste disposal systems, the evaluation process would be unchanged, but
the emphasis  shifts from the waste volume to the treatability and the disposal  of
wastes.  The  evaluation emphasis might also have to be shifted in areas where water
or sewage rates are very high.

Faucet Aerators - Faucet aerators are now very common and are manufactured as
part of most faucet combinations because of the smooth even flow and the lack of
splashing.  Aeration helps remove objectionable tastes and odors, and the aerated
stream of water is more efficient for rinsing than an unaerated stream. It should
be noted, however, that the splashless  characteristics considered desirable and con-
venient may actually result in the use of more water, even though the aerated  stream
it sell is more efficient.  This results from the tendency to use a higher flow rate and
often to let the water run between rinsing operations when there is less splashing.

The use of aerators in the bathroom lavatory and the kitchen sink can save about
two gallons of water each day.  Probably half of this water is heated and an estima-
tion of costs involved should include this fuel savings,  ft should also be specifically
noted that these savings cannot be considered additional since they are already common
in most homes.

Aerators increase the cost of faucets  only slightly and they reduce operating costs
and waste volume.  Aerators do require some maintenance in the removal of mineral
deposits which accumulate in some areas.  There is no effect on effluent quality,
safety or compatibility and the aerated stream is aesthetically more pleasing than
the unaerated stream.  Cost estimates are shown on figure 10.
                                         90

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255
Potable
Supply
            27 gpd      35          5          80          8         100
             1	1	I	I	1	L
(aerator)
Kitchen


laundry


Utility


Bath


(aerator)
Lavatory

Toilet


       255 gpd
      Waste
    Disposal
                     COST ESTIMATES FOR A FOUR MEMBER FAMILY
Material Cost
2 aerators $1.50
Labor Cost
1/6 hr. (non professional)
Total Installation Cost
Expected Life
15 yr.
Cost Per Year
Maintenance and Power Cost Per Year
Cost of Water Saved Per Year
2 gpd (365 day/yr) x $.42/1000 gal
Cost of Power Saved Per Year
(1/2) (2 ffpd) (365 day/yr) x $. 67/1000 «al
Cost of Sewerage Saved Per Year
2 cod (365 day/yr) x $.44/1000 gal
Total Savings Per Year
Net Savings Per Year $.87- $.20
$3.00
0
$3.00

$ .20
0
.31
.24
.32
$ .87
$ .67
                    Figure 10.  Household with Faucet Aerators
                                         91

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                               Rating^ for Aerators

     Initial Cost                                            19.2

     Operating Cost                                        21.2

     Reduction in Waste Volume                             1.1

     Effluent Quality                                       10.0

     Operating Attention                                     7.0

     Aesthetics                                            10.0

     Safety                                                  5.0

     Compatibility with Present Designs

                                    Eating

 Flow Control Shower Heads - Flow control shower heads are merely more economical
 replacements for the conventional type of shower heads.  They can reduce the water
 consumption from the usual 5 to 15 gallons per minute to about 3 gallons per minute
 of showering.  The total amount of water saved will depend on the water pressure of
 the system and the personal habits of the bather.  Using the values for our "average"
 home where the present shower is assumed to deliver 5 gallons per minute and to last
 3 to 5 minutes, the flow control shower heads will save 6 to 10 gallons of water per
 shower.  If showering is the method of bathing sixty percent of the time, the water
 saved is approximately 2200 gallons per year for each person. At least three-
 fourths of the water saved would have been heated and the cost of heating the water
 is an additional savings. Assuming that fuel  oil ($0.15 per gallon) is the source of
 heat this saving is approximately $0.67 per 1000 gallon and the total savings in water,
 sewage, and heating from flow  control shower heads is thus about $3.00 per person
 or $12.00 per "average" family for each year.

 Flow control shower heads are manufactured by several leading manufacturers and
 marketed at prices varying from $3.00 to $15.00. Installation varies from simply
 screwing a new showerhead in place of the old one to complete replacement of the
 piping back to the supply line.  The first case can be easily handled by the home
 owner in 5 to 10 minutes while  a plumber would probably charge $10.00 to $15.00
 in the second case.   Using the higher costs mentioned above, the total cost of
 converting to flow control shower heads would be  $30.00, and the water and fuel
 savings in the "average" home  would amortize the purchase and installation expenses
 in two and a half years.  Thereafter the family would save twelve dollars per year.
 For new homes, the increase in cost over conventional devices would be much less
than the cost of conversion in an older home,  and savings would be correspondingly
greater.

                                         92

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 The flow control showerheads cost approximately 10% more than the conventional
 shower heads but cost less to operate (reduced water and heating costs) and demand
 no additional maintenance or operating attention. The quality of the shower effluent
 is unchanged except for a slight increase in contaminant concentration.  The reduced
 volume fixture does provide a pleasant and adequate shower for cleansing.   There
 may, however, be some aesthetic objection to the reduced flow rate because many
 people particularly enjoy a shower at full force (such a shower often consumes more
 water than a tub bath).  Safety and compatibility are unchanged.

                        Rating for Flow Control Showers
     Initial Cost                                            18.0

     Operating Cost                                         26.7

     Reduction in Waste Volume                             5.0
     Effluent Quality                                        10.0

     Operating Attention                                     10.0

     Aesthetics                                             8.0

     Safety                                                 5.0

     Compatibility with Present Design                       5.0

                                                           87.7

 Low Trap Water Closets - The conventional household water closet uses 4 to 6 gallons
of water per flush and flushing water can amount to more than one third of an
individual's daily water usage. The amount of water required for flushing is governed
by aesthetic criteria for  sufficient water to effectively remove the wastes from the
toilet.  Be redesigning the toilet bowl and the water trap various manufacturers
are producing toilets which require only about 3-1/2 gallons for an adequate flush,
thus saving an average of 1-1/2 gallons per flush or for the "average" individual,
about 7-1/2 gallons per day,  2740 gallons per year.  Again assuming the "average"
rates this is equivalent to a savings of $2.35 per person per year or $9.40 for the
"average" four member family.

The low trap toilets are no different than the normal toilets in operation or
appearance and the only evaluation parameters that would change are initial cost,
operating cost, and waste volume.
                                        93

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235

Potable
Supply
                        35
60
                                                                     100
             1           I          1          1       J	I
1
(aerator)
Kitchen


Laundry


Utility


Flow Con.
Showers
Bath


(aerator)
Lavatory


Toilet

1
235 gpd
Waste
Disposal COST ESTIMATES FOR A POUR MEMBER FAMILY
Material Cost
flow control shower head $15.00
Labor Cost
2 hr. $7.50/hr.
Total Installation Cost
^xpoctod Life
W vr.
Cost Per Year
Maintenance and Power Cost Per Year
Cost of Water Saved Per Year
Cost of Power Saved Per Year
Cost of Sewerage Saved Per Year
Total Savings Per Year
Net Savings
$15.00
15.00
$30.00

2.00
0
3.70
4.40
3.90
$12.00
$10.00 yr.
                Figure 11.  Household with Flow Control Showers
                                        94

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                      Rating for Low Trap Water Closets

    Initial Cost                                            16.5

    Operating Cost                                         28.6

    Reduction in Waste Volume                              6.0

    Effluent Quality                                        10.0

    Operating Attention                                     10.0

    Aesthetics                                             10.0

    Safety                                                  5.0

    Compatibility with Home Plumbing

                                       Total

Automatic Flush Valve Water Closets - The automatic flush valve offers several
advantages for conservation of  water and for design changes  in the bathroom.  The
flush valve operates directly from the water supply line and requires no tank.  The
absence of a tank could allow the utilization of additional space in the bathroom.
Flush valve operation demands larger piping for the household,  at least to the
water closet, in order to supply water at a  sufficient rate to  start the flush siphon.
Therefore, installation of flush valves would require replacement of existing piping
in older homes and the use of larger piping for new homes in addition to the cost
of purchasing and installing the valves.

The system offers the advantage of more controlled volumes of flush water. The
flush mechanism can be set to  deliver a volume of water sufficient for flushing and
no more.  Unlike the conventional flush mechanism, where additional water is lost
as the tank refills,  water flow  stops when the flushing action is over.  Also, with
the tanks water often leaks continuously and unnoticed between flushes.  If the
automatic flush valve begins malfunctioning it is immediately apparent and  repairs
can be made.  The flush valve  offers a ready means of providing a dual flush, which
would use less water to flush away liquid wastes.  This could be accomplished simply
by mounting two valves in a parallel circuit. The automatic  flushing valves
are also adaptable to and could be advantageously  used with the shallow trap toilets.

Initial costs would be higher because of the flush valve cost and the larger size
piping that would be required.  Despite possible maintenance costs,  the total operating
cost would be lower because of the savings  in water and sewerage.  Initial cost and
volume reduction vary with the use of single flush or dual flush systems.  Effluent
quality, operating attention, aesthetics,  safety, and compatibility remain unchanged.
                                         95

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Potable
Supply



	





I 	


	





27 gpd 35 5 80 8 70
1 |


( aeratoi)
Kitchen



Laundry


\

Utility


I

Bath


1
(aerator)
Lavatory


j

Toilet


       f
    225 gpd
Waste Disposal
                     COST ESTIMATES FOR A POUR MEMBER FAMICf
Material Cost
(1 shallow trap water clbset) $70.20
Labor Cost
4 hrs. $7.50
Total Installation Cost
Expected Life 20 years
Cost Per Year
Maintenance and Power Cost Per Year
Cost of Water Saved Per Year
Cost of Power Saved Per Year
Cost of Sewerage Saved Per Year
Total . Savings Per Year
Net Savings
•$ 70.20
30.00
$100.20

5.01
0
4.60
0
4.80
$ 9.40
$ 4.39
          Figure 12.  Household with Shallow Trap Water Closets
                                     96

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               Rating for Automatic Flush Valve Water Closets

                                        Single           Dual
                                        Flush           Flush
    Initial Cost                         9.3               7.4

    Operating Cost                     27.6              33.9

    Reduction of Waste Volume          6.0               9.2

    Effluent Quality                    10                10

    Operating Attention                 10                10

    Aesthetics                         10                10

    Safety                              5                 5

    Compatibility with Home Plumbing   5                 5
                                       82.9              90.5

Reuse of Wash Water for Toilet Flushing - The reuse of wash waters for flushing
toilets is a scheme in which the water from the laundry and from bathing is collected
and used as the flushing liquid in the water closet, thus saving the amount of water
normally used for toilet flushing.  This use of waste wash waters for toilet flushing
is one of the simplest and least expensive methods of conserving water through
reuse.  The water for reuse for flushing toilets does not require high standards,
because it is not to be ingested or to come  in contact with  the body.  It  does not have
to be  heated,  and therefore requirements of a heating system need not be considered.
The detergents from laundry operations should make the water safer from a health
viewpoint since many detergents are bactericidal. Also, the bad taste  of soaps and
detergents  should discourage small children who  might accidentally ingest the water.
The main treatment problem is to make the water aesthetically acceptable to  the
average housewife.

Possible aesthetic parameters for rejection would be foaming, suspended solids,
odor,  and color.  Suspended solids  can be removed by filtration; if odor, foaming,
and color are problems,  the causative agents could be removed by activated carbon.
In the experimental unit used by McLaughlin (55), odor, color, and foaming were no
problem and suspended solids were removed by filtration through a swimming pool
(cartridge type) filter.

The physical requirements of the system are collection of the waste waters,
storage of this water until usage, and a means of supplying the water to the water
closet for use.  To collect the water, existing drains must be rerouted or replaced,
                                       97

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209 to
225 gpd
Potable
Supply







— »— 1 	 , 	 , 	 , — i 	 r


















27 gpd 35 5 80 8 7°~^\
1 1 1 1 1 \^/ 1 12}
t j f 1 t T


(aerator)
Kitchen




Laundry




Utility




Bath



(aerator]
Lavatory

(1) (2)
Flush
Valves
Toilet

1

209-225 gpd COST ESTIMATES FOR A
\Iastf> Disposal FOUR MEMBER FAMILY , Valvp ? Vnl
Material Cost
1 or 2 flush valves $40, piping $20
Labor Cost
5-6 hr. $7.50/hr.
Total Installation Cost
Expected Life 15 yr.
Cost Per Year
Maintenance and Power Cost Per Year
Cost of Water Saved Per Year
Cost of Power Saved Per Year
Cost of Sewerage Saved Per Year
Total Savings Per Year
Met Savings
|6o.oo
37.50
$97.50

$ 6.50
.75
4.6o
0
4.80
$ 9.40
$ 2.15
$100.00
45.00
$145.00

$ 9.65
1.50
7.05
0
7.40
$ 14.45
$ 3. -so
Figure 13.  Households with Automatic Flush Valves for Water Closets
                                  98

-------
and a tank provided for storage.  A filter is required to protect the flushing system
and the pump used to lift the water to the water closet from abrasive solids.  Also,
a pressure tank is required to supply pressurized water to the water closet.  The
pressure tank could possibly be eliminated by slight modifications of the pump and
water closet.

Initial cost, operating cost, and operating attention will increase with this system,
while waste volume will be substantially decreased.  Effluent quality and safety
will not change appreciably, but aesthetic and compatibility factors will depend on the
particular circumstances.

    Initial  Cost                                       4.2

    Operating Cost                                   17.4

    Reduction in Waste Volume                       20.0

    Effluent Quality                                  10.0

    Operating Attention                                9.5

    Aesthetics                                        9.5

    Safety                                             5

    Compatibility with Home Plumbing                 4.5
                                                     80.1

Aerobic Treatment of Wastes - Several manufacturers of aerobic treatment systems
offer maintenance contracts with their treatment units so that no more homeowner
attention is required than for a septic tank.  This service costs additional money,
but helps make the aerobic devices more acceptable to the health authorities who
recognize both the need for periodic maintenance and service and the tendency of
most home owners to neglect maintenance and service so long as possible.  The
treatment system of many of the companies contacted is designed to be buried out of
sight like the septic tank with a similar soil absorption system for disposal of the
treated effluent.   Many of the companies claim that the effluent from their treatment
plant is suitable  for disposal to storm sewers or small water courses.  However,
many health officials do not currently permit such disposal, and we have assumed
the necessity of using a soil absorption system in this analysis.  The advantages of
the aerobic treatment are the greater absorption capacities that most soils exhibit
toward aerobic over septic effluents.  Thus the absorption field can be made smaller
or assumed to last a longer period of time.  In this example an absorption field
1/3 the size required for a septic tank effluent (87) is assumed to be adequate.
                                       99

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155
Potable
Supply
27 gpd
                     35
          4         4
                       4
                                           80
              4          4
            100
       Kitchen
         Laundry
Utility
                                          Bath
          155
   Waste Disposal
Lavatory
                                                     Toilet
                                                     Overflow
                                                        15
                          Collection
                             Tank
                                        PC,
                             Pressure
                               Tank
                    COST ESTIMATES FOR A POUR MEMBER FAMILY
Material Cost
tanks and piping ?95, pump & filter $140
Labor Cost
12 hrs $7.50/hr.
Total Installation Cost
Expected Life
10 yr. (main components)
Cost Per Year
Maintenance and Power Cost Per Year
Cost of Water Saved Per Year
Cost of Power Saved Per Year
Cost of Sewerage Saved Per Year
Total Savings Per Year
Net Savings
$235.00
90.00
$325.00

32.50
3.65
16.10

15.30
31.40
-$ 4.75
  Figure 14.   Households with Reuse of Washwater for Toilet Flushing
                                      100

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In poor soils,  the initial cost of the aerobic system may be substantially less than an
anaerobic system.  The aerobic system requires power roughly equivalent to a home
freezer.  There is no reduction of volume but the effluent is of high quality.  Assuming
the use of a manufacturers service contract, operating attention increases only
slightly.  Aesthetically, an aerobic plant  is more operationally acceptable than a
septic tank, but the greater accessibility  required for maintenance may make the
aerobic system more offensive to some home owners.  Safety and compatibility are
relatively unchanged.

(Note that the  aerobic system is compared to a septic tank in poor soil where the
size of the absorption field for aerobic effluent is assumed to be 1/3 that required
for a septic effluent)

     Initial Cost                                        27. 7

     Operating Cost                                      4.8

     Reduction in Waste Volume                          0. 0

     Effluent Quality                                    15. 0

     Operating Attention                                 9.5

     Aesthetics                                          4.5

     Safety                                              5.0

     Compatibility with Home Plumbing
Distillation of Wastes with Reuse for all but Drinking and Cooking - Although this
treatment scheme has already been eliminated by the preliminary cost analysis,
it is presented again as a comparative example of one of the more complicated treat-
ment schemes.

Available distillation devices cannot handle solid materials effectively without
excessive scaling.  The most inexpensive method of removing and treating the  solids
would be by sedimentation and filtration.  These  could be supplied by a septic tank
and a commercially available pressurized  sand filter.  This clarified liquid would
then be fed to the distillation apparatus.  For simplicity it was assumed that the use
of a vapor compression device such as the Hickman still would be used and that the
significant operating problems had been solved. Also, it was assumed that 85% of
the  feed water will be recoverable in the distillation process without significantly
increasing operating costs.
                                        101

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'->-> &F" 	 ^— -
Potable
Supply












27 gpd 35 5 80 8 100

Kitchen

Laundry

Utility

Bath

Lavatory

Toilet


     I
  255 gpd
                 Aerobic

                Treatment
-^ Soil -Absorption

      (poor soil)
                       COST ESTIMATES FOR A FOUR MEMBER FAMILY
Material Cost
aerobic plant $1200, soil absorption system $800
Labor Cost
included above
Total Installation Cost
Expected, Life
20 yr.
Cost Per Year
Maintenance and Power Cost Per Year
Cost of Water Saved Per Year
J^jst of Power Saved Per Yaa
Cost of Sewerage Saved Per Year (Cost of Septic
Tank System in Poor Soil)
Total Savines Per Year
_Net Savlnes
$2000

$2000

$ 100
51


152

1
Figure 15.  Aerobic Treatment in Place of Septic Tank in Poor Soil Areas
                                     102

-------
55 gpd
>otat>le
Supply
->-
27,

•6P<3
r
Kitchen

-*•




1



^ ,1
Laundry


Settling
and
Digestion
Tank



r
Utility


€f
Pump

Filter
€T
Pump

1



80
Bath


Distilla-
tion

1
Residue
<
Pu

r
TIP







"1
1
^

£

i
Lavatory


Carbon
Adsorption


-

— *







100
1

P
Toilet

rCh
Qisinfeo-
tion



•»






Pres-
surized
Holding
Tank
^
Hot
Water
Heating
Tank

            COST ESTIMATES FOR A FOUR MEMBER FAMILY
Material Cost
pumps & pressure tanks $290, pre treatment $520,
distillation unit $1500, final treatment $250
Labor Cost
Total Installation Cost
Expected Life
15 yr.
Cost Per Year
Maintenance and Power Cost Per Year
pumping $22, pretreatment $12, distillation $160,
final treatment $30
Cost of Water Saved Per Year
Cost of Power Saved Per Year
Cost of Sewerage Saved Per Year
Total Savings Per Year
Net Savings
$2560.00
200.00
$2760.00

18^.00
22U.OO
3^.00
0
114.00
148.00
-$ 260.00
Figure 16.  Distillation and Reuse:  All Water in Poor Soil Areas
                              103

-------
The low temperature operation of this still would prevent the volatilization of many
organic materials but the product water would still require disinfection and carbon
adsorption treatment to make the effluent acceptable for health and aesthetic  standards.

The initial cost and the operating costs of such a system are much higher than under
present systems and the cost savings in water and sewerage are small in comparison
with the costs.  The parameters of operating attention, aesthetics, safely and house-
hold acceptability would also be adversely affected.  The additional equipment re-
quires additional homeowner surveilance and maintenance.  Under normal conditions,
the safety of the water should be insured by the multiple steps of filtration, distilla-
tion, adsorption and disinfection but the chance of malfunction exists, and the
knowledge of possible malfunction would  cause some aesthetic reaction in addition
to the normal dislike for directly reusing waste water. There would be no major
design problems with such a system, but just the bulk of the equipment could cause
some concern.

                   Rating for Distillation and Reuse of All Wastes

     Initial Cost                                       0.5

     Operating Cost                                    8.2

     Reduction in Waste Volume                       17.3

     Effluent Quality                                  10.0

     Operating Attention                                3.3

     Aesthetics                                        8

     Safety                                             3

     Compatibility with Home Plumbing

                                    Total

According to the ratings just presented,  the order of desirability of the waste
reduction and treatment schemes is shown below followed  by a similar ordering
as to net savings per "average family" per year.

Order of Rating                                     Rating

1.   Shallow Trap Toilets                               91.1

2.   2 flush valves with toilet                           90.5
                                        104

-------
Order of Rating (Cont'd)                              Rating
3,  Flow control showers                              87.7
4.  1 flush valve with toilet                             82.9
5.  Reuse  of wash waters for toilet flushing             80.1
6.  Aerators                                           78.5
7.  Aerobic treatment (poor soil areas)                 71.5
8.  Distillation and reuse of all wastes                 54.8

Order of Net Yearly Savings ($)
1.  Flow control showers                             $ 10.00
2.  Shallow trap toilets                                  4.39
3.  2 flush valves with toilet                             3.30
4.  1 flush valve with toilet                              2.15
5.  Aerators                                             0« 67
6.  Reuse of wash waters for toilet flushing              -4.75
7.  Aerobic treatment                                   1.00  (in poor soils)
8.  Distillation and reuse of all wastes                -260. 00  (in poor soils)
When the rating order and the savings  order are combined, the listing of the
processes  in order of practicality becomes:
    1.   Shallow trap toilets
    2.   Flow control showers
    3.   2  flush valves with toilet
    4.   1  flush valve with toilet
    5.   Aerators
    6.   Reuse of wash waters for toilet flushing
    7.   Aerobic treatment
    8.   Distillation and  reuse  of all wastes
 Figures 17 and 18 show the probable costs and savings that would correspond to two
 of the possible combinations of these devices.  Each actual application would be a
 different and individual problem which could be solved in the manner outlined at the
 beginning of this section.
                                         105

-------
 Potablei
 Supply
 115
100
rH
ni
CO
o
p.
CO
•H
ft
4)
-P
CO

£
           27 gpd   " 35
       Kitchen
                  Laundry
            27
      15
                     Utility
                      35
                                             8o
                                           Bath
Lavatory
                                    80
                                                               Toilet
                155
                100
        Collection
             &
          Settling
f


Dn








fc
O



*^
>*/
r^


Pressure
Storage


•*

Distil-
lation
Unit

                                                      S^
                                                      \J
                                                      Punp
                          Pump
300 gal.                 30  gal.

        COST ESTIMATES FOR  A POUR MEMBER FAMILY
                                                   Pressure
                                                    Storage
                                                     Tank
                  Hot Water
                   Heating
                  & Storage
                                                             3° Sal-
Material Cost
pumps & pressure tanks ($250), pretreatment $270,
distillation $1000
Labor Cost
Total Installation Cost
Expected Life 15 yr.
Cost Per Year
Maintenance and Power Cost Per Year
Cost of Water Saved Per Year
Cost of Power Saved Per Year
Cost of Sewerage Saved Per Year
Total Savings Per Year
Net Savings
$1520
200
1720

114
34
22

23
45
-$103
       Figure 17.  Reuse of Non-Sanitary Wastes for Toilet Flushing After
                    Filtration, and for Laundry After Distillation
                                        106

-------
20i> gpd '
Potable
Supply


















27 gpd 35 5 60 8 70
1 1 1 1 \ I


(aerator
Kitchen


Laundry


Utility


Bath

(aerator]
Lavatory


Toilet


       205 gpd
       to T;'actc  Disposal
                    COST  ESTIMATES FOR A POUR MEMBER  FAMILY
Material Cost
1 shallow trap W.C. $70.20,1 flow control
shower $15, 2 aerators at $1.50
Labor Cost
6 hr. $7.50/hr.
Total Installation Cost
Expected Life
Cost Per Year
Maintenance and Power Cost Per Year
Cost of Water Saved Per; Year
Cost of Power Saved Per Year
fios-h nf Spwp-ra £>•<=> Saved Per Year
Total Savings Per Year
Net Savings
$ 83.20
$ 45.00
133.20

6.45
0
8.10
4.37
8.62
$,21.09
$14.64
Figure 18.  Use of Flow Control Showers,  Shallow Trap Toilets, and Aerators
                                      107

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                                      vn

                               SURVEY RESULTS
A postal survey of homeowners, architect-engineers, plumbers, and plumbing
equipment manufacturers was conducted to obtain representative reactions from the
people who would control the actual use of any schemes for reducing water usage or
improving waste treatment and to ensure that the opinions formed from the literature
survey were not contrary to popular practice or beliefs.  The questionnaires were
prepared and distributed throughout the country so that any peculiarities or radical
differences  in the replies caused by climatic or cultural variations in different areas
of the country could be recognized.

The response to the survey was relatively good as 387 homeowners, 40 plumbers,
29 architect-engineers, and 8 plumbing equipment manufacturers, representing 50%
of the equipment manufacturers contacted, 52% of the homeowners, 21% of the
architect-engineers, and 18% of the plumbers,  filled out and returned the question-
naires.  The higher return from the equipment manufacturers and homeowners was
probably due to the fact that many from these groups were personally contacted by
phone or in person by personnel from the different General Dynamics divisions around
the country. Many of the survey participants submitted additional suggestions and
comments on the environmental pollution problem in general and on particular points
in the different questionnaires.  In addition,  slightly more than half of the cooperating
homeowners asked to receive a summary of the survey results and conclusions.

The responses received showed no major differences in the opinions of the people;
from the various sections of the country; nor did the responses differ significantly
with the cost of the homes.  Comparison of the answers from homeowners with sewer
connections with the answers and comments from homeowners with individual waste
disposal systems also revealed no significant differences.

The questionnaire distribution schedule and samples of the questionnaires with the
tabulated results of the survey are included in the appendix (tables VA through DC A).
The pertinent results related to the use of the water reduction devices and techniques
are shown in table XTV,  and the following section presents a brief discussion of all
the survey results.

WATER SAVING FAUCETS AND SHOWERHEADS

As shown by table XTV, all of the groups surveyed were favorable toward the use of
the flow restricting faucets and showerheads.  Most of the objections to these devices
seemed to stem from aesthetic rather than functional or economic considerations.
                                        108

-------
Water Saving
Device or Technique
Table XIV. Summary Of Survey Results

       Percent of Responses Which Indicate Acceptance for
       the Use of These Techniques or Devices	
Water Saving Faucets
or Shower Heads
                           Homeowners   Plumbers
           87
87
                                  Architect-
                                  Engineers
90
                     Equipment
                     Manufacturers
75
Direct Flush Toilet
Valves
           92
49
79
72
Toilets with Separate
Flush Cycles for Urine
and Feces

Home Urinals
79
37
56
24
90
77
43
43
Toilets that Disinfect
and Reuse Flush Water
           46
21
68
The Reuse of Wash Waters
a.  For Toilet Flushing         82
b.  For Lawn Irrigation         82
                                     86
                                     86
                                       109

-------
Some seemed to fear that showering enjoyment would be curtailed by the reduced
flow.  One of the architects surveyed was opposed because he thought the flow
reduction was to be achieved through spring loaded,  rather than flow restricting
valves.

The equipment manufacturers and plumbers predicted that the flow reduction devices
would be 10% to 30% more expensive to purchase and possibly somewhat more costly
to install,  although no particular installation problems were foreseen.

DIRECT FLUSH TOILET VALVES
Direct flush toilet valves received the highest percentage (92%)  of homeowner
approval of all the water saving devices.  However,  architect-engineers, plumbers,
and plumbing equipment manufacturers gave the direct flush valves a lower rating.

Noise and the requirements for higher water pressure or larger pipe sizes were the
main objections. Although many plumbers  mentioned noise,  only two of the 387
homeowners mentioned noise as a problem. The pressure or pipe size requirement
can be alleviated rather simply by increasing the pipe size.  To some plumbers
and homeowners, the direct flush valves were considered to be preferable to the
tank type because of their dependability and waste flow reduction.

Toilets with Separate Flush Cycles for Urine and Feces
Toilets with separate flush cycles for urine and feces are a relatively new concept
in this country and its unfamiliarity was probably the cause for the lower percentages
favoring their use.  Comments from plumbing equipment manufacturers indicated
that the major problems anticipated are more costly installation and maintenance
requirements.  Also, they suggested that if it is difficult to change cycles, the cycle
using the most water will be used exclusively. One  of the plumbers objected because
he felt that the reduced flush for urine would not properly cleanse the toilet bowl.
Homeowners also seemed to fear that a dual flush system would be difficult to use and
expensive to maintain.   However, judging from some of the European designs and
their public acceptance, most of these objections appear unfounded and most objections
could be apparently removed by simple demonstrations and explanations.

HOME URINALS

Home urinals were considered objectionable by 63%  of the homeowners, 23% of the
architect-engineers,  57% of the equipment manufacturers, and  76%  of the plumbers.
The major objections stated were the extra cost and bathroom space required for the
urinal; however, the  study by Kira (45) indicated that the major objections against the
use of urinals are actually psychological in origin and as a result household acceptance
will probably not be readily induced by practical and economic considerations.
The feasibility of this explanation is somewhat strengthened by  the greater homeowner
approval of recycle toilets which are sanitarily, aesthetically,  economically, and
operationally less acceptable than the urinal.


                                          110

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RECYCLE TOILETS

Most survey participants objected to the household use of recycle toilets.  The major
objections were the initial expense and the fear that unsanitary conditions would
develop.  Handling the wastes when the holding tank is filled could be avoided by con-
necting the discharge directly to the sewer, but the problem of higher initial and
operating costs would remain,  as would the possibility of odor if the device is not
properly maintained.

REUSE OF WASTE WASH WATERS

The reuse of waste wash waters appears to be generally acceptable to architect-
engineers and homeowners, although many questioned the degree  of treatment to be
given the waste waters and some named specific limits to what they would accept.
For example,  the water for toilet flushing must not appear dirty,  be odorous, or
stain the toilet bowl and require more frequent cleaning;  for irrigation water many
mentioned the necessity of removing soaps, bleaches,  and  other substances poten-
tially harmful to plants.  One of the architect-engineers stated that he  had already
designed wash water reuse systems for water short areas,  and several others men-
tioned that they had designed systems using municipal aerobic treatment effluent.

INDIVIDUAL TREATMENT SYSTEMS

Of the 149 homeowners with individual treatment systems,  90% used a  septic tank
and soil absorption system and 10% used a cesspool soil absorption system.  In
most of the treatment systems  (68%) the laundry and bathing waters are treated in
the same system as the sanitary wastes as suggested by the "Manual of Septic Tank
Practice" (90).

It was surprising to note that although 67% of the maintenance schedules reported by
the homeowners were inadequate according to recommendations in the  Public Health
Service manual, only 40% experienced any recent need for  service or repair and 60%
of those requiring service needed only routine removal of accumulated solids.
Generally,  the homeowners and the architects seemed satisfied with the operation
of the septic tank soil absorption system.  Apparently, this acceptance of the septic
tank system is based on satisfactory performance rather than merely low costs,
as the average costs reportedly allocated for individual sewage treatment by the
architect-engineers and which the  homeowners indicated  they would be willing to
pay were not low enough to encourage the use of unworkable systems.  Only 40% of the
homeowners indicated desire for a more effective system and only 50% felt that even
a trouble-free system was worth more money.  Many felt their present system was
already trouble-free.

Aerobic treatment systems were not used by any of the 387 homeowners responding
and only 17% of the architect-engineers had found it necessary or convenient to even
consider aerobic treatment rather than a septic tank.  One  architect said he had
installed several units which operated quite successfully, although the  initial costs
were high.


                                       Ill

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                                      vm

                   CONCLUSIONS AND RECOMMENDATIONS
This report presents a useful composite of available waste treatment information
for individual households and introduces an area of household water and waste
management (waste prevention) which has previously received little attention in this
country.  The conclusions of the study are presented below and then discussed along
with appropriate recommendations for additional activities.

CONCLUSIONS

Household Water Use

    1.   Quality requirements for specific household tasks can be safely lowered.

         Many household tasks do not require water of drinking qualify. Many of the
         established standards are related to taste or odor, and water of lower quality
         could be used for practically all purposes except those associated with
         drinking or food preparation.  Standards are suggested for bathing, general
         cleaning, and toilet flushing.  The practicality of using differing water
         qualities for various tasks depends on the availability and cost of the
         alternate water systems.

    2.   Household water usage can be significantly reduced.

         There are many household functions in which water is used wastefully.
         Water for bathing, toilet flushing, and laundry could be economically
         reduced approximately 35% by use of presently available devices and tech-
         nology. In a city of 100,000 these savings could amount to more than two
         million gallons of water per day that would not have to be supplied to the
         users and eventually treated in the waste treatment plant.

         The reduction in household water use is an attractive and practical way
         of aiding the fight against water and waste problems.  Waste prevention
         is one method of pollution control that will not become obsolete as new treat-
         ment technology is developed. No matter what the method of treatment
         either for large installations or for individual homes,  handling and treatment
         of the waste  will be more efficient and less expensive when it is concentrated
         in a smaller volume.  For example, septic tank treatment efficiency depends
         on the residence time of the sewage in the septic tank, a factor inversely
         proportional to the waste flow to the system. The soil absorption system
        will also perform more efficiently since the septic tank effluent will have
        been more completely settled and treated, and the soil will have a greater

                                         112

-------
         opportunity to rest and regain infiltrative capacity because of the reduced
         flow.  Reduced flow would also enhance the performance of aerobic treatment
         units by allowing longer periods for oxidation in the aeration chamber and
         more efficient settling in the  settling compartment.

         Some manufacturers have anticipated the demand for plumbing devices that
         use less water.   Valves which restrict flow for faucets and showers, toilets
         which use reduced flushing volumes, and washing machines which allow
         just the required amount of water to be used are already available. A new
         toilet with flushing quantities  similar to the United  Kingdom toilets has just
         bean, introduced (House and Home, April, 1969).  Other innovations such
         as the dual flush cycle toilet will probably be introduced in this country in
         the near future.

    3.   A limited public opinion survey showed little opposition to the use of flow
         reducing devices.

The survey of the homeowners, plumbers, architect-engineers, and equipment
manufacturers substantiated most of the opinions formed during the study and indicated
ready acceptance for all the water reduction devices except the home urinal and the
recycle toilets.  The relatively good response to the survey showed that public
interest in protecting and preserving the environment is high.  Most of the survey
participants seemed to favor the concept of flow reduction devices but were somewhat
hesitant to accept them in their own homes.  Many of the architect-engineers and
plumbers seemed interested, but skeptical, and said they lacked data on most of the
devices.

In addition to the indication of which water reduction devices and techniques would be
most acceptable in the home, the survey showed the interest most people have in
reducing environmental pollution.  An  increasing number of people are aware of the
environmental pollution problems and  of the economic and aesthetic effects that
these problems have on their own lives.  In a national public opinion survey for the
National Wildlife Federation, George H.  Gallup,  Jr. reported that three of four
Americans from all income groups are willing to pay more taxes to improve their
natural environment  (Air/Water Pollution Report, p. 72, March 3, 1969).  In the
Niagara peninsula of Ontario, interested citizens have organized The Committee
of a Thousand, a group of dues-paying citizens who are personally involved in the effort
to discover and terminate all sources  of pollution in their area (Watertalk, 1969).

Household Treatment and  Possible Reuse

    1.   There is no simple solution to the problem of waste treatment for individual
         households.

         Individual household waste treatment will continue to be a problem in the
         foreseeable future.  Individual treatment units are being installed at a
                                       113

-------
  decreasing rate, but the numbers being installed and the number already in
  use are very large. Household aerobic treatment units are presently the only
  available alternative to the septic tank system and are practically competitive
  with the septic tank only in areas of poor soil. Surface disposal of aerobic
  effluents,  which would help reduce aerobic treatment costs, cannot be recom-
  mended without the provision of adequate safeguards to ensure an effluent that
  will not endanger health or degrade the surrounding environment. Require-
  ments for nutrient removal from effluents could further increase the cost of
  disposing effluents to  surface drainage.

  The problem of individual household treatment will be of great importance for
  many years and the development of a more efficient, more economical system
  would be very profitable.  The increasing population densities and the greater
  demands for high quality recreational waters  are making operation of in-
  adequate individual treatment units more noticeable and objectionable.

  Besides the need for better treatment, there is a need for better maintenance
  of equipment and better understanding of the treatment process by the home-
  owners.  Many homeowners would give their treatment system  proper care if
  they had a better understanding of its operation.  Information is available from
  many government agencies, but builders, septic tank installers, and possibly
  even an agency such as the Welcome Wagon could help to make  sure all home-
  owners with individual treatment systems had the necessary information.

2. Advanced waste treatment schemes other than simple filtration and disinfec-
  tion are generally not practical for a normal household.

  Most households could not meet the operating expenses or provide the
  operating attention required by the majority of the advanced treatment systems.
  Even when an extensively treated water is reused for all purposes but
  drinking,  the costs are prohibitive. The only economical and practical
  reuse is the filtration and reuse of wash waters  for toilet flushing, and in
  areas where aerobic treatment is economical, the filtration and reuse of the
  aerobic effluent for toilet flushing.  Where possible, the reuse  of wash waters
  is preferable to the reuse of effluent from a septic tank or an aerobic treat-
  ment unit. With wash waters the treatment is much simpler and the  danger of
  disease infection  is more easily avoided.

  While advanced waste treatment schemes do not seem generally practical
  for individual home usage under the restrictions of present technology,
  progress may depend  on a single development which could occur at any time.
  One of the advanced treatment techniques (oxidation by activated oxygen
  produced through gamma radiation) which was considered unsuitable  for
                                     114

-------
        household use earlier in this study has reportedly been developed as a
        household treatment process (Chemical and Engineering News, p. 61,
        April 21,  1969).  A chemical treatment process, reportedly applicable for
        households, is being tested at Washington State University.  Changes in
        treatment requirements and developments in other areas such as in auto-
        matic controls could make other treatment systems acceptable in the house-
        hold.

        Similarly, developments which could make the advanced treatment processes
        suitable for household use would make reuse schemes possible.

RECOMMENDATIONS FOR ADDITIONAL ACTIVITIES

Household Water Use

    1.  Studies on water quality and contaminant detection should be continued.

        Although household water systems utilizing different levels  of water quality
        for different uses do not appear generally practical for the common house-
        hold,  more work should be sponsored in the area of water standards and
        their  measurement. The presence of many new chemicals which are difficult
        to treat or remove and which may be dangerous in very small concentra-
        tions  is increasing the need for higher standards of water quality control.
        The present level of waste recycling in many of the river systems as well
        as a growing number of intentional reuses will intensify this need in the near
        future.  More knowledge is needed on the effect of many chemicals and the
        means of  detecting and removing those chemicals which may be found
        harmful.
    2.  Flow  reduction concepts should be more extensively promoted  and publicized.

        Many persons contacted in the public opinion survey, including many
        plumbers  and architect engineers, had not heard of the various flow reduc-
        tion devices and had received no information on them.  Manufacturers
        should provide the architect-engineers and plumbers with factual information
        on the design, operation,  and cost of these items as well as data on the
        potential savings available to customers and to society in the form of better
        water and waste management.   It would also be advantageous for the manu-
        facturers  to directly contact large businesses,  industries, and public
        institutions where many water and waste systems are often concentrated
        in one or  two locations and where additional per unit savings are possible
        in material and labor costs.

        An impartial demonstration of the use and water saving capabilities of these
        water reduction devices would also be very beneficial in securing public
        support and in providing data which could be used for design purposes as
        these devices become more common.  At first,  it  might seem that such  a
        study would be redundant  in that equipment manufacturers probably already
                                       115

-------
         have extensive data on the operation of the particular device which they
         market.  However, household usage does not always correspond to the\
         manufacturers' criteria; nor do homeowners always use equipment exactly ~
         as directed.  The proposed evaluation should not only reveal possible
         difficulties, but more importantly,  provide data for typical costs (installation,
         maintenance,  repair, etc.) and typical savings in water and fuel that could
         be expected in a normal home.  Such information would be very useful to
         architect-engineers, plumbers, homeowners,  and the equipment manu-
         facturers themselves.   It would also provide the data for an analysis of any
         conflicts with local plumbing codes and where  necessary should provide
         adequate data for changes in antiquated legislation.

         In the first phase of the recommended study, a representative group of
         families should be chosen for the tests and their present water using system
         thoroughly surveyed as to the frequency of usage and the amount of water
         used in each of the household functions.  For the second phase  of the study
         the flow reducing devices would be installed and the same data  would be
         recorded.  In addition,the reactions of the families to the use of these
         devices would be carefully examined.

     3.  The use of community schemes for more efficient water and waste handling
         should be further investigated.

         Waste collection and water distribution systems must be studied on a
         community, rather than an individual, basis.  Two potentially lower cost
         waste collection systems have been proposed; both systems, a pressure
         system and a vacuum system,  allow smaller diameter waste lines and
         eliminate the need for the excessively deep trenches required with gravity
         sewers.  In the pressure system, the sewage is ground and pumped through
         a check valve from each household into small diameter pressurized sewer
         lines.  In the vacuum system wastes are transported from  specially designed
         water closets by a central vacuum system.  This system has the added
         advantage of using only  a tenth as much flushing water.  Each system
         requires special equipment in the household and each would therefore re-
         quire some additional maintenance.  Potentially these schemes could
         substantially reduce the cost of sewer lines and, for the vacuum system,
         reduce water requirements; but more information is needed before either of
         these systems or a combination of the two can  be recommended. Con-
         sideration must also be given to the effect such changes would have on the
         water system,  the waste treatment system, and on other utilities such as
         power.

Household Treatment and Reuse

    1.   Additional studies should be conducted to clarify the effect  of a  higher
         quality sewage effluent on a soil absorption system.
                                        116

-------
    Previous studies have not clearly substantiated claims for a greater soil
    absorption capacity with aerobic effluents.  Further information is needed
    to permit effective regulation of the soil absorption systems for aerobic
    treatment.
2.  Criteria for the design, construction, operation, and effluent quality of
    household treatment systems must  be developed before the surface discharge
    of treated effluents can be permitted.
    Individual household treatment systems are administered primarily by local
    officials who often do not have the background to adequately check individual
    household systems without the aid of such detailed criteria. The criteria
    developed should be general enough to apply throughout the country and to all
    types of treatment systems and should include provisions requiring safe-
    guards to prevent the discharge of  inadequately treated effluent.

3.  Research on improved individual waste treatment systems should be
    continued.
    The large number of homes depending on  individual treatment systems, and
    the sometimes less than adequate service of available treatment units  insure
    a ready market for an improved treatment system, whether it is a com-
    pletely new system or a modification of existing systems.  Because of the
    septic tank's low maintenance and generally acceptable service, further
    improvement of septic tank design  would seem a logical  starting place.
    Most present designs have been related more closely to  construction ease
    than to treatment efficiency,  but new materials and new  fabrication tech-
    niques may permit designs that encourage higher treatment efficiency  and
    better maintenance.  As an example, one possible design change which would
    theoretically improve septic tank digestion and solids removal would be the
    combination of the principles of the anaerobic contact process and the
    anaerobic filter (105).  Improvement of aerobic treatment systems and the
    development of entirely new  concepts should also be encouraged.  Poten-
    tially, the aerobic treatment units  can  provide better waste treatment than
    anaerobic units; however,  safety requirements indicate that subsurface
    filters are still desirable.  The development  of controls to economically
    monitor and control the effluent quality would encourage acceptance of aerobic
    treatment units with surface disposal.
4.  An effort should be made to channel the high public interest in environmental
    protection into constructive public  action.
    One possibility for extending and exploiting present public interest would be
    an effort to involve youth organizations in the program to combat deteriora-
    tion of the environment.  Many youth organizations, especially those like
    scouting with many outdoor activities,  should welcome and actively  support
    programs to cleanse and protect our polluted land and water resources.
    The ideas and practices fostered by such activities could also stimulate
    interest and activity in the adult segment of the population.
                                    117

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                                        118

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13.    Campbell, L. A., "A Feasibility Study of a Completely Recycled Water System
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                                         119

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26.    Crisp, J. and Sobolev, A.,  "An Investigation of the Performance of Lavatories
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27.    Gulp, G.  L.,  "High Rate Clarification of Waste Waters",  paper presented at
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28.    Dague,  R. R., McKinney, R. E., and Pfeffer,  J. T., "Anaerobic Activated
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       Pyrolysis Water Recovery System Utilizing Radioisotopes for Thermal
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33.    Flaherty, W.  F., "The Effect of Water  Reuse on Water Quality",  Water
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34.    Fox, J.  J.,  Engineering Manager, Laundry Equipment Division, Westing-
       house Electric Corp.,  146 E. 4th.St., Mansfield,  Ohio 44901.  Letter to
       J. L. Dodson, October 11, 1968.

35.    Foyn, E., "Removal of Sewage  Nutrients by Electolytic Treatment",  Verb.
       Internat. Verein. Limnol., XV, 569-579,  February 1964.

36.    Garthe,  E. C., and Gilbert, W. C.,  "Wastewater Reuse at the  Grand Canyon",
       JWPCF,  Vol.  40, No.  9, p. 1582, September 1968.

37.    Geinopolos,  A., Wullschleger,  R. E., and Mason, D. G., "Engineering
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38.    Hall, E.  P.  (Chairman Committee on Water Pollution from the  Operation of
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                                        120

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39.   Haney,  P.  D.  and Hamann, C. L., "Dual Water Systems", JAWWA, Vol.
      57, No. 9,  p.  1073, September 1965.

40.   Hanna,  G.  P., Jr. and Shumate,  K. S., "Evaluation of Effects of Enzyme
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41.   Harrison,  F.  E., Managing Director, Cisterns Limited Addingham, nkley,
      Yorks,  U.  K., Letter to V. T. Boatwright Jr., September 1968.

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43.   Jackson, J. K., Bonura,  M. L., and Putnam, D. F., "Evaluation of a Closed
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      York, N. Y. 10001,  Letter to J.  L. Dodson,  General  Dynamics, Electric Boat
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47.   Kolega, J. J., Wheeler, W. C., and Hawkins,  G.  W., Jr.,  "Current Septic
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48.   Kolnsberg, H. J., and Dudarevitch, M. D.,  "Water Reclamation by
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49.    Linaweaver, F. P.,  Jr., "Report on Phase One, Residential Water Use
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51.    Ludwig, H. F., and Stewart,  J., "Equilibrium Percolation Test for Estimating
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                                        121

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 52.    Mason, D. G.,  "Engineering Evaluation of Reverse Osmosis and Ion Exchange
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 53.    McGauhey, P. H. and Winneberger, J.  H., "Studies of the Failure of Septic
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 54.    McKee, J. E.,  and Wolf, H. W., Water Quality Criteria.  Second Edition.
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 55.    McLaugnlin, E. R., A Recycle System for Conservation of Water in Residences.
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 56.    McNeil, W., "Urine Evaporator", USAF Aero Medical Laboratory, Wright
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 57.    Michaels,  A.,  Membranes, the Thin Difference.  Industrial Research, April
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 58.    Miller, H. C.,  and Knipe, W., "Electrochemical Treatment of Municipal
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 59.    Morris, J. C.,  "Conventional Approaches Not Enough",  Chemical Engineering
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 64.    Ohio State University Engineering Experiment Station, "A 23-Month Study of
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                                        122

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65A.   Olsson,  E.,  Karlgren,  L.,  and Tullander, V., "Household Waste Water",
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66.    Parker,  U.  R., Installation Engr., Sloan Valve Co.,  4300 West Lake Street,
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67.    Pecis, J. C., Vice  President Research & Development, Speakman Co.,
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70.    Preul, H. C., "Underground Movement of Nitrogen", JWPCF, Vol. 38,  No. 3,
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72.    Ranum,  J. M.,  Executive Director, Corporate Public Affairs, Whirlpool
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73.    Reid, G.  W., "Projection of Future Municipal Water Requirements",  South-
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74.    Robeck,  G.  G., Cohen, J. M.,  Sayers, W.  T., and Woodard, R. L.,
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75.    Scott,  J.  A., "Health Considerations Involved in the Treatment and Disposal
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79.    Sobolev, A.,  and Lloyd, C. J., Building Research Station, Garsten,
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86.    Thomas, R. E.,  and Bendixen, T. W.,  "Domestic Water Use in Suburban
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87.    Thomas,  H. A.,  Jr., Coulter, J. B., Bendixen, T. W., and Edwards, A. B.,
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101.    Winneberger, J. H., and McGauhey, P. H.,  "A Study of Methods of
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                                         125

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104.   Witherow, J.  L.,  Coulter, J.  B., and Ettinger, M. B., "Suburban Sewage
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105.   Young, J. C., and McCarty, P. L.,  "The Anaerobic Filter for Waste
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                                         126

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Ames Research Center, "The Closed Life-Support System",  report prepared by
National Aeronautics and Space Administration, April 1966.

Aquatic Life Advisory Committee of the Ohio River Valley Water Sanitation Com-
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1960.

Baffa,  J. J., and Bartilucci, N. J., "Waste Water Reclamation by Ground Water
Recharge on Long Island",  JWPCF Vol. 39, No. 3,  March 1967.

Barduhn, A. J., "Where Do the Chemical Engineers Come In?", Chemical Engineering
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Bendixen, T. W.,  Thomas, R.  E., and Coulter, J. B.,  "Study of Seepage Pits",
Robert A. Taft Sanitary Engineering Center, May 1963.

Clark, B. D.,  "Houseboat Wastes, Methods for Collection and Treatment", Federal
Water Pollution Control Administration, June 1967.

Coulter, J. B., and Bendixen,  T.  W.,  "A Study of Serial Distribution for Soil
Absorption Systems", Robert A. Taft Sanitary Engineering Center, April 1959.

Committee on Rural Sanitation, "Rural Sanitation",  American Journal of Public
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Coulter, J. B., Bendixen,  T. W.,  and Edwards, A.  B., "Study of Seepage Beds
Part I",  Robert A.  Taft Sanitary Engineering Center, February 1960.

Coulter, J. B., and Bendixen,  T.  W.,  "Report to Federal Housing Administration
on Study to Determine if Distribution Boxes can be Eliminated Without Inducing
Increased Failure of Disposal Fields",  Robert A. Taft Sanitary Engineering Center.

Coulter, J. B., "Limitations on the Use of Septic Tank Systems", Robert A. Taft
Sanitary Engineering Center.

Coulter, J. B., Bendixen,  T. W.,  and Edwards, A.  B., "Study of Seepage Beds",
Report to the Federal Housing Administration by the Robert A. Taft Sanitary
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Coulter, J. B., "Sewage Disposal Systems Applicable to Subdivisions", paper
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Coulter, J. B., Soneda, S., and Ettinger, M.  B.,  "Preliminary Studies on
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                                       127

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 Coulter, J. B., Bendixen, T. W.,  and Edwards, A. B.,  "Study of Seepage Beds,
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 Hydo, C.  G., "The Beautification and Irrigation of Golden Gate Park with Activated
 Sludge Effluent", Sewage Works Journal,  Volume 9, No. 6,  November 1937.

 Inglefinger, A. L., Secord,  L.  C., and Arndt, W. F., "Life Support System
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 p. 38, January 1964.

Jones, J.  H., and Taylor,  G. S., "Septic Tank Effluent Percolation Through Sands
 Under Laboratory  Conditions",  Soil Science, Vol.  99, No. 5.
                                       128

-------
                    ADDITIONAL REFERENCES (Cont'd)

Ledbetter, J. O., "Can We Afford Zero Health Risks", Water and Sewage Works,
Vol.  115, No. 9, p.  438,  September 1968.
LeGrand, H. E., "A Broad View of Waste Disposal in the Ground",  Water and
Sewage Works, Vol. 114, R.  N., P. R-179.
LeGrand, H. E., "Management Aspects of Ground Water Contamination", JWPCF,
Vol.  36, No. 9, September 1964.
Lubitz, J. A., Benoit, R. J., Wallman,  H.,  and Adamson,  T. E.,  "Wash Water
Reclamation for Extended Duration Space Voyages", paper presented at 1st American
Institute of Aeronautics and Astronautics  Annual Meeting at Washington,  D.  C.,  June
1964.
Mattson,  R.  J.,  and Tomsic, V. S., "Improved Water Quality", Chemical  Engi-
neering Progress, Vol. 65, No. 1, January 1969.
McGauhey, P. H., and Winneberger, J. H., "A Study of Methods of Preventing
Failure of Septic Tank Percolation Systems", booklet published by Department of
Housing and  Urban Development, Federal Housing Administration, October 1967.
McKee, J. E.,  "Reclaimed Sewage Water Socially Okay", Environmental Science
and Technology,  Vol. 3, No.  1,  January 1969.
McMahan, A. A., and Bendixen, T. W.,  "Report to the Federal Housing Administra-
tion  on the Frequency of Occurrence of Water-Using Appliances in Suburban Homes
Having Individual Sewage Disposal Systems", March 1961.
Merten, U., "Reverse Osmosis", General Atomic Division of General Dynamics,
May 1965.
Merten, U., Nusbaum, I., and Miele,  R., "Organic Removal by  Reverse Osmosis",
paper presented at the American Chemical Society Symposium on Organic Residue Re-
moval from Waste Waters, September 1968, Atlantic City, N. J.
Metzger, C. A., Hearld, A. B., and McMullen, B.  G., "Water Recovery  from
Human Waste During Prolonged Confinement in the Life Support System Evaluator",
Aerospace Medical Research Laboratory, Wright-Patters on Air Force Base,  Ohio,
April 1966.
Metzger, C. A., Hearld, A. B., and McMuUen, B.  G., "Evaluation of Water
Reclamation Systems and Analysis of Recovered Water for Human Consumption",
AMRL-TR-66-137 WPAFB,  February 1967.
Michaels, A. S., "New Separation Technique for the C. P. I. ", Chemical Engineering
Progress, Vol. 64,  No. 12,  December 1968.
National Academy of Sciences, National Research Council, "Alternatives in Water
Management", 1966.
                                       129

-------
                      ADDITIONAL REFERENCES (Cont'd)

Neale, J. H., "Advanced Waste Treatment by Distillation", report for the Advanced
Waste Treatment Research Program, U. S. Dept. of Health, Education, and Welfare,
March 1964.
Nichols, D.  C., "Water Reclamation from Urine Thermoelectric System", AMRL-
TR-65-29, WPAFB, March 1965.
Nuccio,  P.  P.,  and Jasionowski, W. J., "Automatic Water Recovery System",
AMRL-TR-67-155, WPAFB,  March 1968.
Oakley,  H.  R.,  and Cripps, T., "British Practice in the Treatment of Waste Water",
JWPCF, Vol. 41,  No. 1, January 1969.

 Pecoraro, J. R.,  Pearson, A. O., Drake, G. L., and Burnett, J. R., "Contributions
of a Developmental Integrated Life Support System to Aerospace Technology", paper
presented at American Institute of Aeronautics and Astronautics, 4th Annual  Meeting
and Technical Display at Anaheim,  California, October 1967.
 Porges, R., and Morris, G.  L., "Extended Aeration Sewage Treatment,  A Pre-
liminary Evaluation",  publication of the U. S. Public Health Service, Robert A.
Taft Sanitary Engineering Center 1960.
Robeck, G. G., Bendixen,  T. W.,  Swartz, W. A., and Woodward, R. L., "Factors
Influencing the Design and Operation of Soil Systems for Waste Treatment",
JWPCF, Vol. 36,  No. 8, August 1964.

Ryan, M. J., and Edgerley,  E., "Water Recovery from Human Liquid Wastes by
Distillation and  Chemical Oxidation",  USAF School of Aerospace Medicine, Brooks
Air Force Base, Texas, December 1967,

Slonim,  A. R.,  "Rapid Procedures to Monitor Water for Potability", Aerospace
Medicine, Vol.  39, No. 11, November 1968.

Stanford Research Institute, "Long Range Planning Report:  "Water",  Report No.
16, September 1959.

Stephan, D. G., and Weinberger, L. W., 'Waste Water Reuse — Has ft 'Arrived'",
paper presented at 40th Annual Conference of the Water Pollution Control Federation,
New York, N. Y., October 1967.

Stevens, D. B., "Wastewater Reuse,  Status in New York State", paper presented
at the 40th Annual Meeting of the Water  Pollution Control Federation in New York
City, N. Y., October 1967.

Sudak, R. G., and Nusbaum,  I., "Pilot Plant Operation of Spiral Wound Reverse
Osmosis Systems", paper presented at the Western Water and Power Symposium,
April 1968, at Los Angeles, Calif.
                                        130

-------
                   Table A-l.  Waste Treatment Manufacturers*
 Manufacturer Contacted
 1.  Fifer Industries Inc.
 2.  DuPont
 3.  Gulf General Atomic
                                  Location
                             Louisville, Ky.
                             Wilmington, Del.
                             San Diego, Calif.
 4.  Hamilton Southern Assn.  Hickory, N. C.
 5.  Jet Aeration Co.
 6.  Valdespino Labs
 7.  Dorr Oliver
 8.  Rex Chain Belt
 9.  Yeomans
10.  General Electric Co.
11.  Cromaglass Corp.
12.  Converto  Co.
13.  Wilson Water Purif.
     Company
14.  BIC>2 Systems Inc.

15.  Svenska Interpur Ab
16.  Allenaire, foe.
17.  Convert-All, Inc.
18.  Microphor,  Inc.
19.  Sewerless Toilet Co.
                             Cleveland,  Ohio
                             Orlando, Fla.
                             Stamford, Conn.
                             Milwaukee, Wis.
                             Melrose Park,  fll.
                               Type Process
                     "Fiferator" Aerobic Stabilization
                     Reverse Osmosis
                     Reverse Osmosis
                     Aerobic Stabilization
                     Aerobic Stabilization
                     Aerobic Stabilization
                     No Process
                     No Process
                     Aerobic Stabilization
                             Schenectady,  N. Y.   Aerobic Stabilization
                             Williamsport, Pa.    Aerobic Stabilization
                                                  Aerobic Stabilization
                                                  Hypochlorination
Montreal, P. Q.
Buffalo, N. Y.
                             Kansas City, Mo.

                             Stockholm, Sweden
                             Warren,  Ohio
                             Brunswick,  Maine
                             Willits, Calif.
                     Aeration Stabilization Trickle
                     Filter
                     Spiral Bio-Filter
                     Aerobic Stabilization
                     Aerobic Stabilization
                     Aerobic Stabilization
                     Aerobic Stabilization
                             Lafayette,  Indiana
Of the nineteen manufacturers listed above fourteen made individual home treatment
units  or contemplated making them.  These fourteen are:
1.  Fifer Industries                        8.   Wilson Water Purification Co.
2.  Yeomans (Cavitette)                    9.   BiO2 Systems
 3.  Cromaglass Corp.
 4.  Converto Co.
 5.  Jet Aeration Corp.
 6.  Valdespino Labs
 7.  Hamilton Southern
                                          10.  Svenska Interpur Ab
                                          11.  Allenaire,  Inc.
                                          12.  Convert-All, Inc.
                                          13.  Microphor, Inc.
                                          14.  Sewerless  Toilet Co.
 *Mention of a commercial product or manufacturer does not imply endorsement by
  the Federal Water Pollution Control Administration.
                                         131

-------
      Table A-n.  Manufacturers Supplying Information On Plumbing Fixtures*

 Plumbing Valves & Fittings
     Harcraft Brass,  Torrance, Gal.
     Speakman Company, Wilmington, Del.
     Water Saver Faucet,  Chicago, 111.
     Mueller Brass Company, Port Huron, Mich.
     Sloan Valve Company, Chigago,  HI.
     Milwaukee Faucets, Inc.,  Milwaukee, Wis.
     Beacon Valves, Waltham,  Mass.

 Plumbing Fixtures and Water Closets
     Kohler Company, Kohler, Wis.
     Eljer Plumbingware Co., Pittsburg, Pa.
     American Standard Controls Div., NYC, N. Y.
     Monogram Industries, Inc.
     Incinomode Inc., Garland,  Texas
     LaMere Industries, Walworth, Wis.

 Major Appliances
     Norge
     Westinghouse
     Whirlpool
     General  Electric Co., Schenectady, N.Y.
     Kelvinator Division
     Kitchen Aid Hobart, Troy,  Ohio
*Mention of a commercial product or manufacturer does not imply endorsement by the
 Federal Water Pollution Control Administration.
                                      132

-------
             Table A-m.  Cost Data For Liljendahl* Vacuum Toilet
                           COST COMPARISON NO.  1

Estimated cost including a comparison of conventional versus vacuum closets in a
single home:

    1.   Home with conventional closets:
        A.  3" plastic pipe and vents for closets, lavatories,
            baths and sink                                   $280.00

        B.  2-conventional closets @ $25, 00 each              $  50.00

        C.  Labor (Installation)                              $165.00
                                           Total              $495.00

    2.   Home  with vacuum closets:
        A.  2" plastic pipe and vents for lavatories,
            baths and sink                                   $175.00
        B.  1-1/2" plastic pipe for closets                    $60.00
        C.  2-vacuum closets @ $57.00 each                  $114.00

        D.  Labor (Installation)                              $175.00
                                           Total              $524.00

    3.   Cost of vacuum collection system for single
        home installation, including vacuum pumps,
        tank,  miscellaneous piping, gages, electrical
        equipment and sludge transport unit.                   $1300.00

    4.   Cost of vacuum collection system for 100 homes,
        including vacuum pumps, tanks, miscellaneous
        piping, gages,  electrical equipment,  sludge pump
        and shelter                                          $7500. 00
*Mention of a commercial product or manufacturer does not imply endorsement by
 the Federal Water Pollution Control Administration.
                                       133

-------
                              Table A-m.  (Cont'd)


                          COST COMPARISON NO. 2

The cost of water used by the conventional closet versus the vacuum closet was
evaluated based on the following information received from private industry,
government, state and local authorities:

    1.   People per home - 4.5

    2.   Total gallons per day per person - 75

    3.   Water rates (national average)

    4.   Gallons per day per person used by conventional closet - 30

    5.   Gallons per day per person used by vacuum closet - 2-1/4
         (based on present design)

         A.  Cost of water used in home per month with        $6.29
            conventional closet

         B.  Cost of water used in home per month with        $3.71
            vacuum closet
                                    Savings per  month      $2.58
                         COST COMPARISON NO. 3

The additional cost of electricity to operate the vacuum pump was estimated based
on $. 015 per K. W. H.:
    1.  Additional cost for single home vacuum collec-        $ .837
        tion system with 1/4 HP pump per month
    2.  Additional cost per home in allotment of 100           $ ,183
        homes with vacuum  collection system with 5 HP
        pump per month
                                      134

-------
                     Table A-FV.  Preliminary Cost Comparisons (Annual Cost in Dollars per Person)
w
Ol
                 System

      1.   Conventional Systems
      (a)  Sewers (average water cost)
      (b)  Septic tank, good soil
      (c)  Septic tank, fair soil
      (d)  Septic tank, poor soil
      (e)  Sewers (low water cost)
      (f)   Sewers (high water cost)
      2.   Flow Control Showers
      3.   Flow Control Faucet
          (Kitchen or Lavatory)
   Annual                       Waste       Total
Equipment and      Water     Disposal      Annual
Operating Cost      Cost        Cost         Cost
Annual Savings;
( - ) Indicates
Increased Costs
L/UQUJ






\
)
(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
(f)
/QT7TTP 1X7 O ^"OT* /"><"\O1
\**"6« WdtcZ UOol
/QT7TI" *\X7O ^"O Y* OrtOl
\**»S* Wd-Lci UObl
y j j
^a.vg. water cosi




$0.50
0.50
0.50
0.50
0.50
0.50
0.80
0.80
0.80
0.80
0.80
0.80
i-\ in nn
I) J.U. \>\J
h\ in fin
Ly ±v. UU
t\ -I A no
[J J.U. UU
4 en
. ou
98 Rf\
6o, ou
9.10
9.10
9.10
9.10
4.30
26.00
9.70
9.70
9.70
9.70
4.60
27.70
*P -L v • O \J
non
. £i\J
1 a in
J.D. -L U
qo an
•JO. I U
i n t;n
-LU. O\J
1 n c;n
-LU. OU
9.50
10.20
14.70
30.80
9.50
9.50
10.10
10.80
15.60
32.70
10.10
10.10
ip£l\J Q ij\J
01 on
^1 . £i\}
OC 1 A
^D. J.U
4Q "7n
"±o. ( U
i K Qn
-LO. oU
QQ i n
oy. j.u
19.10
19.80
24.30
40.40
14.30
36.00
20.60
21.30
26.10
43.20
15.50
38.60









$1.40
1.40
1.80
3.30
1.00
3.10
-0.10
-0.10
0.00
0.50
-0.20
0.50

-------
                                                   Table A-IV.  (Cont'd)
                System

      4.   Faucet Aerators
      5.
co
O)
Automatic Flush
Valve Toilets
      6.
Automatic Flush
Toilets (2 Cycles)



(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
/*\
Annual
Equipment and
Operating Cost
$0.05
0.05
0.05
0.05
0.05
0.05
1.65
1.65
1.65
1.65
1.65
1.65
2.60
2.60
2.60
2.60
2.60
2.60

Water
Cost
$ 9.92
9.92
9.92
9.92
4.70
28.30
8.90
8.90
8.90
8.90
4.20
25.40
8.30
8.30
8.30
8.30
3.90
23.70
Waste
Disposal
Cost
$10.42
11.10
16.00
33.40
10.42
10.42
9.40
10.10
14.50
30.00
9.40
9.40
8.80
9.50
13.60
29.10
8.80
8.80
Total
Annual
Cost
$20. 39
21.07
25.97
43.37
15.17
38.77
19.95
20.65
25.05
40.55
15.25
36.45
19.70
20.40
24.50
40.00
15.30
35.10
AnnualSavings;
( - ) Indicates
Increased Costs
$0.11
0.13
0.13
0.33
0.13
0,33
0.55
0.55
1.05
3.15
0.05
2.65
0.80
0.80
1.60
3.70
0.00
4.00

-------
                                                    Table A-IV.  (Cont'd)
co
               System
      7.   Shallow Trap Toilets
      8.
English Style
Toilets
      9.
English Style
(Dual Flush)



(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
(f)
Annual
Equipment and
Operating Cost
$ 1.60
1.60
1.60
1.60
1.60
1.60
1.20
1.20
1.20
1.20
1.20
1.20
1.40
1.40
1.40
1.40
1.40
1.40

Water
Cost
$ 8.70
8.70
8.70
8.70
4.10
24.80
7.90
7.90
7.90
7.90
3.80
22.50
7.20
7.20
7.20
7.20
3.40
20.50
Waste
Disposal
Cost
$ 9.10
9.80
14.20
29.70
9.10
9.10
8.30
9.10
13.10
27.30
8.30
8.30
7.50
8.30
12.00
25.10
7.50
7.50
Total
Annual
Cost
$ 19.40
20.10
24.50
40.00
14.80
35.50
17.40
18.20
22.20
36.40
13.30
32.00
16.10
16.90
20.60
33.70
12.30
29.40
Annual Savings;
( - ) Indicates
Increased Costs
$ 1.10
1.10
1.60
3.70
0.50
3.60
3.10
3.00
3.90
7.30
2.00
7.10
4.40
4.30
5.50
10.00
3.00
9.70

-------
                                                  Table A-IV. (Cont'd)
               System



      10.  Vacuum Flush Toilet

          Single Home
      11.  Recycle Toilets
CO
oo
      12.  Incinerator Toilets
Annual
Equipment and Water
Operating Cost Cost
(a)
(b)
(c)
(d)
(e)
(0

-------
                                                 Table A-IV.  (Cont'd)
CO
CD
               System

     13.  Reuse of Wash Water
          for Toilet Flushing
14. Multifiltration
    (All Non-Sanitary
    Wastes)
     15.  Reverse Osmosis



(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
(f)
Annual
Equipment and
Operating Cost
$ 9.10
9.10
9.10
9.10
9.10
9.10
34.00
34.00
34.00
34.00
34.00
34.00
118.00
118.00
118.00
118.00
118.00
118.00

Water
Cost
$ 5.90
5.90
5.90
5.90
2.80
16.80
4.10
4.10
4.10
4.10
2.00
11.70
4.10
4.10
4.10
4.10
2.00
11.70
Waste
Disposal
Cost
$ 6.70
7.50
10.60
21.30
6.70
6.70
4.30
5.30
7.60
15.90
4.30
4.30
4.30
5.30
7.60
15.90
4.30
4.30
Total
Annual
Cost
$ 21.70
22.50
25. 60
36.30
18.60
32.60
42.40
43.40
44.70
54.00
40.30
50.00
126.40
127.40
129.70
138.00
124.30
134.00
Annual Savings;
( - ) Indicates
Increased Costs
$ -1.20
-1.30
.50
7.40
-3.30
6.50
-21.90
-22. 20
-18.60
-10.30
-25.00
-10.90
-105.90
-106.20
-103.60
- 94.30
-109.00
- 94.90

-------
                                             Table A-IV.  (Cont'd)
16.
              System

Distillation (All
Non-Sanitary Wastes)
17.
Distillation (All
Wastes - Reuse
Except Drinking)
18. Aerobic Treatment



(a)
(b)
(c)

-------
                                             Table A-IV.  (Cont'd)
19.
20.
21.
             System

Electrolytic Treat-
ment (In Place of
Septic Tank)
Biological Treat-
ment (Reuse Except
for Drinking)
Coagulation Sedi-
mentation and
Filtration (All
Wastes .Reuse for
Toilet Flush)



(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
(f)
(a)
(b)
(c)
(d)
(e)
(f)
Annual
Equipment and
Operating Cost
$ 53.00
53.00
53.00
53.00
53.00
53.00
57.00
57.00
57.00
57.00
57.00
57.00
35.00
35.00
35.00
35.00
35.00
35. 00

Water
Cost
$ 10.00
10.00
10.00
10.00
4.80
28.60
1.50
1.50
1.50
1.50
0.70
4.30
5.70
5.70
5.70
5.70
2.70
16.30
Waste
Disposal
Cost
$ 2.60
2.80
4.00
8.40
2.60
2.60
1.60
2.70
3.90
8.00
1.60
1.60
6.00
6.80
9.90
20.60
6.00
6.00
Total
Annual
Cost
$ 65.60
65.80
67.00
71.40
60.40
84.20
60.10
61.20
62.40
66.50
59.30
62.90
46.70
47.50
50.60
61.30
43.70
57.30
Annual Savings;
( - ) Indicates
Increased Costs
$ -45.10
-44.60
-40.90
-27.70
-45.10
-45.10
-39.60
-40.00
-36.30
-23.20
-44. 00
-23.80
-26.20
-26.30
-24.50
-18.40
-28.40
-18.20

-------
                                                  Table A-IV.  (Cont'd)
*>.
IS9
                      System

      22.  Coagulation Sedimen-
          tation,  Filtration
          Adsorption (Reuse
          Except for Drinking)
23. Carbon Filtration
    and Adsorption of
    Non-Sanitary Wastes
    (Reuse Except for
    Drinking)



(a)

-------
                    Table A-V.  Questionnaire Distribution

Localities in which questionnaires have been distributed:
    1.  San Diego,  California
    2.  Rochester, New York
    3.  Avenel, New Jersey
        Newark,  New Jersey
        New York,  New York
    4.  Tulsa, Oklahoma
        Dallas, Texas
        Oklahoma City, Oklahoma
        Ft. Worth, Texas
    5.  Chicago, Illinois
    6.  Ft. Walton Beach, Florida
        Cocoa Beach, Florida
    7.  District of Columbia
    8.  New London, Connecticut
    9.  Pomona, California
Approximate number of questionnaires distributed in each locality:
    Home Owner Questionnaires                55
    Plumbing Contractor Questionnaires        25
    Architect-Engineer Questionnaires         15
Sixteen (16) questionnaires were sent to a representative group of plumbing equip-
ment  manufacturers throughout the country.
                                        143

-------
                     Table A-VI. Results of the Survey of Homeowners
No. of
Response
   (387)     1.   Approximately what is the market value of your home?
                24  less than $15, 000  241 $15, 000 to $30, 000 l£2_over $30, 000
   (387)     2.   How many people live  in your home ?	adults  	children under 21  (no correlation)
                (include non-family members of household).
   (387)     3.   Where do you get the water for your home?  (check one)
               285 city water system  66 jprivate well  38	community well
   (387)     4.   Do you have city sewer service ? 247  yes  140 no
                If your answer is yes, go to question 15.  If your answer is no, complete
                entire questionnaire.
   (149)     5.   How do you dispose of bathroom and kitchen waste waters?
                a.   septic tank, soil absorption 134
                b.   cesspool 15
                c.   other,  please specify	
   (167)     6.   What maintenance do you give your sewage disposal system? (please check)
                a.   Pump out septic tank when plumbing is sluggish  47
                b.   Add chemicals to  septic tank when plumbing is sluggish 26
                c.   Pump out septic tank every three years  24
                d.   Check tank every  year and pump out when needed  32
                e.   Other,  please describe	38	
   (139)     7-   How do you dispose of laundry waste water ?
                a.   With bathroom and kitchen waste waters   94
                b.   In a separate  system   45   what type ?   Soil Absorption (90%)	
            8.   Has your waste disposal system needed service or repair in the past
                three  years ?
                53  yes   33  minor (less than $50)    80  no
                           20	major (over $50)
   (133)     9-   How many years has the system been in operation? average 10.9 yr.
   (141)    10-   Do you think that you need a more effective system?   57  yes     84  no
   (133)    11-   Would you be willing to pay more for a trouble-free system?  66  yes  67 no
                                             144

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                                 Table A-VI. (Cont'd)
(136)    12.   Would you prefer an individual household treatment system or a community
             treatment system?

             55  individual household system   81  community system

(134)    13.   Septic tank systems cost between $500 and $2000 to install.  Would you
             consider the same price range to be a reasonable cost for obtaining a
             system that would provide service comparable to that provided by city
             sewers?   no yes    24	no

(127)    14.   The city sewer service charge (often included in property taxes or collected
             with water charges) varies from about $25 to more than $200 per year.
             Would you be willing to pay a comparable price for similar service for
             your home ?    7? yes   50  no

        15.   Would the reuse of treated waste water from bathing or laundering be
             acceptable to you for:

(374)         a.  Toilet flushing  306 yes    68 . no

(371)         D-  Lawn or garden watering  303 yes     68  no

        16.   Would you object to using any of the following water saving devices tn
             your home ? (Please check one column for each device)
                                                          Would            Would Not
                                                          Object            Object
(376)        &•  Water saving faucets and shower heads
                 that deliver adequate, but not excessive
                                                            51                325
 (378)        b.  Direct flush toilets such as are found
                 to most public restrooms and which use
                 only about 1/2 the water of the common
                 tank type toilet.                            32                346

 (365)        c.  Toilets with separate flush cycles for
                 liquid and solid sanitary wastes.             78                287

 (366)        d-  Home urinals.                             231_                135
 (366)        e-  Toilets that disinfect and reuse flush
                 water many times, such as those
                 found on  the planes of major airlines.        197                1$$

 (370)   17.  Do you feel that your water and waste disposal systems prevent your family
             from being exposed to disease ?  312  yes    56  no
 (387)   18-  Do y°u wish to have a summary of the information obtained from this questionn-
             aire sent to you?  196 jyes   19lno
             If yes,  please provide your  name and address on the separate sheet of paper
             enclosed.

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  Table A-VF  Results of The Survey of Plumbing Contractors


No. of
Responses
1.


(38)
(39)
(36)

(39)
(36)



2.




(38)
(42)
(26)

(35)
(24)



In Private
Homes

Yes No
Have you ever installed any of these
devices? Check "yes" or "no" for
each use.
a. Water saving faucets or shower heads. 27 11
b. Direct flush valves for toilets 18 15
c. Toilets with separate flush cycles
for urine and feces 4 31
d. Urinals 12_ lg_
e. Toilets that disinfect and reuse
flushing water many times, such as
those found on jet aircraft 1 34
f. Other, please specify
Do you foresee particular installation difficulties with any of

No Installa-
tion Problem
(check)
a. Water saving faucets or shower heads 37
b. Direct flush valves for toilets 25
c. Toilets with separate flush cycles for 16
urine and feces
d. Urinals 30
e. Toilets that disinfect and reuse flushing
water many times, such as those found
on jet aircraft ^
f. Other, please specify
In Commercial
Applications

Yes No



24 13
35 4

5 31
35 4


2 34

these devices?
Possible
Installation
Problem
(Please Describe)
1
17
10

5


10

(Use additional page if necessary)
                             146

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                                       Table A-VII (Cout'd)
No. of
Responses
   (40)
   (38)

   (37)

   (32)

   (34)

   (33)
   (40)
   (42)

   (38)

   (38)
           3.   If, in your opinion,  the installation of these devices would require increased
               costs, do you think homeowners would accept these costs ? (Check one column
               for each device.)
                                                                               Increase
                                                      No        Increase       Required
                                                   Increase     Required        But Not
                                                   Required  And Acceptable  Acceptable
(39)
(31)
(34)
(29)
b.
c.
d.
e.
        Water saving faucets or shower
        heads

        Direct flush valves for toilets
        Toilets with separate flush
        cycles for urine and feces
        Urinals

        Toilets that disinfect and
        reuse flushing water many times,
        such as those found on jet air-
        craft
               f.   Other, please specify
                                                                  24
                                                                 JL4
                  .15

                  .18.
                                                                                 .. 21
4.  Would you recommend installation of any of these devices in private homes?
    (Please check)
                                                                     Yes   No

    a.  Water saving faucets or shower heads

    b.  Direct flush valves for toilets
    c.  Toilets with separate flush cycles for urine and feces

    d.  Urinals
    e.  Toilets that disinfect and reuse flushing water many times,
        such as those found on jet aircraft
                                                                                     26
                    Other,  please specify
5.  Without considering cost, how would you rate public acceptance of these devices
    in single family homes ? (Check one column for each device.)
                                                Favorable  Neutral   Opposed

    a.  Water saving faucets or shower heads        27         9         _4__

    b.  Direct flush valves for toilets                1%        13	     17
    c.  Toilets with separate flush cycles for
        urine and feces
    d.  Urinals
.13—
16 .
                    ZL-.
                                                147

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                                       Table A-VH.  (Cont'd)
No. of                                                   Favorable  Neutral   Opposed
Responses                                                             10        21
   (36)        e.  Toilets that disinfect and reuse             _£	      	     	
                  flushing water many times, such
                  as those found on jet aircraf t

              f.  Other, please specify	,_    	      	     	
          6   Additional comments or suggestions:
                                              148

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              Table A-VIJL  Results of the Survey of Architects and Engineers
No. of
Responses
   (29)     1.   Please indicate your major design interest:
                   housing            single family       apartments and
                11 developments  _7	homes         29  commercial buildings

   (29)     2.   Various devices designed to minimize water consumption and waste water
                volume (e.g., water saving faucets and shower heads, direct flush toilet
                valves, home urinals) are now commercially available.  In your present
                designs for private and development housing do you ever specify the use
                of such devices? _9	yes    20  no
                If answer is yes, please specify	


           3.   Would you object to specifying any of the following water saving devices:
                                                                  Would  Would Not
                                                                             Object
   (29)          a.  Water saving faucets or shower heads            J*	        21
   (28)          b.  Direct flush toilet valves                        J>	        22
   (29)          c.  Toilets with separate flush cycles for urine
                    and feces                                      j!	       „
   ;26)          d.  Home urinals                                   Jj	
   (28)          e.  Toilets that disinfect and reuse flush water
                    many times such as those found on the planes
                    of major airlines                               _9	        19.
                f.   Other, please specify
   (21)     4.  Approximately what cost do you usually figure for waste disposal syh.-c.ns
                (not including internal plumbing) for homes that will not be connected to a
                city sewer system? average   $1100; Range $500 to 2000.

            5.  What cost do you usually figure for connecting to the municipal sewer system
                (not including internal plumbing) ?   average $325; Range $25 to 900.	
                                               149

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                                     Table A-Vm.  (Cont'd)

No. of
Responses
             6.  What maximum cost for either a private or community waste disposal system
                do you think would be acceptable to a home buyer ?
                                                                                Annual
                                                                      Initial   Operating
                                                                       Cost      Cost

   (14)          In homes valued at less than $15,000                       $410     $45
   (14)          In homes valued at $15,000 to $29,999                      fi4R       65
   (13)          in homes valued at $30,000 and up                          900       75

   (28)       7.  In your designs would you find acceptable the reuse of treated waste water
                from, bathing and laundering for toilet flushing or for lawn and garden
                 irrigation?    24  yes     4  no

                Please  comment.
   (25)       8.   In your designs have you considered replacing septic tanks with individual
                 household aerated treatment units?   _5	yes   25	no

                 Please comment.
  (16)       9.   in housing developments of more than twenty-five homes do you usually
                 specify community sewers and sewage treatment?    9  yes   _7	no
                 Please comment.
                                                150

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                                      Table A-VEI. (Cont'd)
No. of
Responses
   (28)

   (23)

   (25)
            10.   Do you think that others In your profession would object to the following
                 proposals ?
     Specification of water saving plumbing devices
     Specification of aerobic treatment systems
     Specification of water reuse systems

11.   What leeway does the plumbing contractor have in selecting substitutes for
     the systems specified in the contract?
Most
Others
Would
Object
_0 	
1 	
2 	
Most
Others
Would Not
Object
28
22
_23_
            12.   Additional comments or suggestions:
                                               151

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       Table A-R.    Results of the Survey of Plumbing Equipment Manufacturers
No. of
Responses                                                                       l£5  No
            1.   Does your company manufacture any of the following
                water saving devices at the present time ? (please check)
   (8)           a.  Water saving faucets or shower heads                           JL  _JL
   (6)           b.  Direct flush toilet valves                                       _2_  _£_
   (6)           c.  Toilets  with separate flush cycles for urine and feces            JJ_  _g_
   (7)           d.  Home urinals                                                 _1_
                e.  Other, please specify	  		        _—
            2.  Do you anticipate an increased demand from homeowners
                and contractors for any of these devices in the near future?
                (please check)
   (8)           a.  Water saving faucets or shower heads                          Jl_
   (6)           b.  Direct flush toilet valves                                       J_   _JL
   (7)           c.  Toilets with separate flush cycles for urine and feces            _1_   _6
   (7)           d.  Home urinals                                                 _2_   _5
                e.  Other,  please specify	        	
                Comments:
            3.  If you are not now  manufacturing any  of these devices, do you
                have plans to manufacture any of them in the near future ?
                (please check)
   (6)           a.  Water saving faucets or shower heads                          _!_   J
   (5)           b.  Direct flush toilet valves                                      _L_   _!
   (6)           c.  Toilets with separate flush cycles for urine and feces             _1_  J>
   (6)           d.  Home urinals                                                 3—  JL
                e.  Other,  please specify		
                                               152

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                                      Table A-IX. (Cont'd)

No. of
Responses                                                                         Yes  No
              4.  Would you begin manufacturing any of these devices if
                  increased water rates, sewage rates, or fuel rates for
                  water heating made water conservation more attractive ?
                  (please check)
   (5)             a.  Water saving faucets or shower heads                         *	  _	
   (5)             b.  Direct flush toilet valves                                      ^	  jj	
   (7)             c.  Toilets with separate flush cycles for urine and feces           1	  6	

   (7)             d.  Home urinals	  _	
                  e.  Other,  please specify	  	
    (5)
               5.   Please estimate selling cost of these devices if manufactured
                   on a mass production basis. Again, it is stressed that only
                   estimates are asked for and that these figures will be used
                   only to approximate a total for system cost.
    (5)             a.   Water saving faucets or shower heads $10-20; $18; 50-80% more. 10% more;
    v '                                                     	   30% more
    ^3)             b.   Direct flush toilet valves   $8; $25;  20% more	

    (3)             c.   Toilets \yith separate  flush cycles for urine and
                       feces $88, $60, 50%  more	
    (3)             d.   Home urinals  $40, $40, 10% less
                   e.  Other, please specify
               6.   How would these costs compare with the present retail cost of
                   the systems now used?
                                                        Less        More    No Significant
                                                                                Change

                   a.   Water saving faucets or shower
                       heads
                   b.   Direct flush toilet valves
    /5\             c.  Toilets with separate flush
                       cycles for urine and feces
    /5\             d.  Home urinals
                   e.  Other,  please specify
                                                 153

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                                        Table A-IX. (Cont'd)

No- of                                                                             Yes  No
Responses
             7.  Do you think these devices would be more difficult for
                 plumbers to install than conventional hardware ?
   (8)            a.  Water saving faucets or shower heads                          £	  -	
   (6)            b.  Direct flush toilet valves                                      0     6
   (6)            c.  Toilets with separate flush cycles for urine and feces            2	   4	
   (6)            d.  Home urinals                                                 0	   6	
                 e.  Other, please specify	        	  	
                 Comments:
             8.  How would you rate public acceptance of these devices in private homes.
                                                           Favorable    Neutral    Opposed
   (8)            a.  Water saving faucets or shower heads      4          2         2
   (7)            b.  Direct Hush toilet valves                  3          2         2
   (7)            c.  Toilets with separate flush cycles
                     for urine and feces                        2          1         4
   (7)            d.  Home urinals                             3          0        _4	
                 e.  Other, please specify                    	    	     	
             9.  Additional comments or suggestions:
                                                154
                                                              * U. S. GOVERNMENT PRINTING OFFICE : 1970 O - 405-432

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