IN ARID REGIONS


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, develop-
ments and demonstration activities of the Federal Water
Quality Administration,, Department of the Interior,
through inhouse 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.

Additional copies of this report may be  obtained by
addressing a request to:

       Treatment and Control Research Program
       Robert S  Kerr Water Research Center
       P  0  Box 1198
       Ada, Oklahoma  74820

            IN ARID REGIONS
               Edited by
           James P. Law, Jr.
        Research Soil Scientist
           Jack L. Witherow
  Chief, Agricultural Wastes  Section
Treatment and Control Research Program
 Robert S. Kerr Water Research Center
          Ada, Oklahoma 74820
                for the


          Program //13030 DYY
             October, 1970

           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.

An international conference entitled "Arid Lands in a Changing World",
sponsored by the American Association for the Advancement of Science
Committee on Arid Lands and the University of Arizona, was held at
Tucson in June, 1969.

The Federal Water Quality Administration provided financial support for
the conference and solicited papers to be presented in the Water Manage-
ment and Salinity and Desalinization sessions.  This report presents a
selected group of the papers presented at those sessions which will benefit
those concerned with water quality management problems in arid regions.

The editors wish to acknowledge the cooperation they received from the
authors in the completion of this task.
                                    James P. Law, Jr.
                                    Jack L. Witherow
Ada, Oklahoma
October, 1970


           Percy P. St. Amant and Louis A. Beck

           Gary N.  Dietrich and L.  Russell Freeman

           H.  B.  Peterson, A.  A.  Bishop,  and J. P. Law,  Jr.

           Stanley  J.  Dea

           Norman A. Evans

           Richard  C. Bain,  Jr. and John  T.  Marlar

 NATURAL POLLUTION  IN ARID LAND WATERS                                 79
           John M.  Neuhold

           Allen Cywin, George Rey,  Stanley  Dea, and  Harold Bernard

          Anthony V.  Resnik and John M.  Rademacher



                  Percy  P.  St. Amant and Louis  A. Beck —

The  San  Joaquin Valley  of  California  is the  largest  single agricultural
area in  the  State.   The nearly  eight  million acres  (3.24 x 10" ha) of
irrigable  land  of this  Valley is  one  of the  richest  agricultural  areas
in the world.   Massive  water import facilities have  recently been
constructed  to  assure that  sufficient water  is available for irrigation.
Now  that water  is available much  of the irrigable land  is being developed
for  crop production.  However,  as often happens, the solving of one
problem  develops another.   This problem is how to dispose of the  saline
agricultural wastewaters that result  from irrigated  agriculture.  The
U. S. Bureau of Reclamation has begun construction of the San Luis
Drain to transport  these wastewaters  from Kettleman City on the south
to the western  edge  of  the  Sacramento-San Joaquin Delta near Antioch.
The  State  is continuing studies with  the aim of constructing a drain
at a later date to  provide  drainage for the  rest of  the Valley.

In 1965, the Federal Water  Pollution  Control Administration (FWPCA)
began an investigation  of  the effects of the proposed San Joaquin Master
Drain upon the  quality  of  receiving waters.  (The San Joaquin Master
Drain considered both the Federal and State  drainage facilities.)
In 1967, the FWPCA  report  "San  Joaquin Master  Drain Effects on Water
Quality  of San  Francisco Bay and Delta" indicated that  serious pollution
problems would  likely result if the wastewaters were discharged into
the  Bay  System.   Nitrogen,  primarily  in the  nitrate  form, is the  most
serious  potential pollutant.  This  report also recommended that no
wastewater be emptied into  the  Bay  System until a suitable method for
nitrate  removal has been developed  and that  studies be  vigorously
pursued  during  1967, 1968,  and  1969 to firmly  establish the economic
feasibility of  nitrogen removal treatment of San Joaquin Valley agricultural

In January 1967,  representatives of the U. S.  Bureau of Reclamation
(USSR),  the FWPCA,  and  the  California Department of Water Resources (DWR),
met  to discuss  the  findings of  the  FWPCA's report.  It  was at this time
that the Interagency Agricultural Waste Water  Treatment Center was
established.  The objective of  the  Center was  to determine an economically
feasible method  of removing nitrogen  from the  agricultural wastewaters
of the San Joaquin Valley.  The estimated Summer peak wastewater flow
into the Bay System after the year  2000 will be about 700 million gallons
per day  (2.65 x  10  cu m/day).   The estimated  constituent concentrations
in San Joaquin  Valley agricultural wastewaters is shown in Table 1.
     —  Project Director, San Joaquin Project, Federal Water Pollution
Control Administration; and Chief, Quality and Treatment Unit, California
Dept. of Water Resources, Fresno.

                               TABLE 1
      Chemical Constituents
       Concentrations in mg/1
After 50 yrs of Operation
Total Dissolved Solids

   Non-Time Varying Constituents
       Concentrations  in mg/1
     Total Nitrogen
     Total + Organic Phosphate
     Dissolved Oxygen
     5 Day B.O.D.
     Sufactant (ABS)
     Phenolic Material
     Grease and Oil


Prior to 1967, the California Department of Water Resources had made
arrangements to utilize U. S. Bureau of Reclamation land along the
Delta-Mendota Canal near Firebaugh, California, for construction of
pilot-scale algae stripping facilities.  With the start of the
Interagency study, this area was expanded to include space for
desalination and bacterial denitrification studies.  The organization at
the Firebaugh Treatment Center is quite unique (Figure 1).  The most
unique feature of the Center is the intermingling of personnel.  The
Center is guided by a committee consisting of a project director from the
DWR and the FWPCA and a designated representative from the USER.  This
committee is assisted by a Board of Consultants comprised of Drs. Oswald,
Golueke, and McCarty.  Essentially, the work at the Center is providing
each of the three agencies with more information at a lesser cost than
would have been possible with three separate single-agency studies.

Methods of nitrate removal being studied at the Center include algae
stripping and bacterial denitrification.  Two methods of bacterial
denitrification are being evaluated:  pond denitrification and filter
denitrification.  Desalination is also being evaluated.


The FWPCA, through an agreement with the Office of Saline Water  (OSW),
is evaluating two methods of desalination of agricultural wastewaters—
reverse osmosis and electrodialysis.  The reverse osmosis unit evaluated
was operated at a pressure of 750 psi  (52.7 kg/sq cm) using a cellulose
acetate membrane.  With this unit up to 93 percent ion removal was
experienced using 6,000 mg/1 wastewater.  In the electrodialysis unit
tested, about 30 percent of  the ions were removed each time the waste-
water was passed through the membrane  stack.   Of the two units evaluated,
neither unit significantly removed the boron ion.  The reverse osmosis
unit removed about 20 percent of the nitrate ions, while the electro-
dialysis unit removed about  the same percentage as it did the other ions.

Algae Stripping

The basic theory of algae stripping to remove  nitrogen is quite  simple--
grow a crop of algae which ties up the nitrogen in their cell  structure
and  then remove the algae from the water.  However,  it is not  as  simple
as it sounds.  While algae will grow quite easily  in this water,  the
dense crop of algae required to remove 90 percent of the nitrate-nitrogen
is another problem.  Our  studies at Firebaugh  have indicated that  the
agricultural wastewaters  lack both phosphate and iron  in  the amounts
required to grow  this dense  crop of algae.  We have  tied up 90 percent
of the nitrogen in the  algal cell  structure with the addition  of  phosphate
and  iron.  Algal nutrition studies were conducted  in flasks at  the  Center.
The  effect of individual  growth parameters  (nutrients, depth, detention
time, mixing, etc.) were  studied in small growth units.  The results  of
the  experiments in the  small growth units were combined  to determine  the
operating conditions for  the quarter acre growth pond.  The results from
this  large growth pond  were  then scaled up to  prototype  size.


                  fft*PC A)

The removal of the algae from the water is an even more difficult
problem than growing a dense crop of algae.  Methods which will be
investigated at Firebaugh for algae removal include centrifuging and
micro-screening.  The most promising method, however, is flocculation
and either sedimentation or flotation.  We have been able to achieve
over 95 percent removal of algal cells by flocculation and sedimentation
using either alum, lime or polyelectrolytes--all at approximately the
same cost.  After we have concentrated the algae by either sedimentation
or flotation, it must be dewatered.  This summer we will be operating
pilot-scale units to test dewatering by centrifugation and vacuum

The disposal of the algae may pay part of the cost of treatment.
Several concerns have expressed interest in the use of algae for such
things as animal feed, soil conditioner, or for production of adhesives.
In livestock feed, algae would replace the fish meal or protein supplement
and have a value of approximately $150 a ton  ($165/metric ton).
Poultry raisers are also interested in using algae for feed.  Besides
the protein, algae contains xanthopyll, which adds color to the flesh
of the bird and to the egg yoke and increases the market value.  The
company interested in using algae as a soil conditioner predicts that
algae may be used by the home gardener similar to the use of Milorganite
(condition the soil as well as having some fertilizer value.)  Algae
would have a value of about $100 a ton ($110/metric ton) as a soil
conditioner.  A value of about $120 a ton ($132/metric ton) could be
realized by utilizing algae in the production of adhesives.  If none
of these methods of disposal are practiced, it may be necessary to
dispose of algae by digestion.  The methane gas produced could be used
to provide power required for the treatment process.  Laboratory
experiments by Dr. Oswald indicate that the methane produced by digestion
would produce more power than required in the treatment process.

Bacterial Denitrification

Bacterial denitrification is accomplished through the use of micro-
organisms which, in the absence of dissolved  oxygen, oxidize organic
material and reduce the nitrate-nitrogen  to nitrogen gas.  A wide
variety of common facultative bacteria have the ability to bring about
denitrification.  Denitrification of nitrates is a two-step process
in which the nitrates are reduced to nitrites and then to nitrogen gas.
This method poses no by-product waste disposal problem.  However, the
organisms can only achieve denitrification if they are supplied with
an organic energy source.  Since the agricultural wastewaters are very
low in organic materials, it is necessary to  add an organic source to
the water.  At  the Firebaugh Treatment Center methanol is added to the
wastewater to supply  this required organic source.  We are actively
evaluating two methods  of bacterial denitrification at the Firebaugh
Center:  pond denitrification and filter  denitrification.

Pond Denitrification

Relatively deep ponds  are used in this process to develop the required
anaerobic conditions.  After methanol addition, the wastewater enters
near the bottom of the pond at a detention time of 5-20 days and the
nitrogen-free water is discharged at the top of the pond.  The denitrifying
organisms are free-floating in the pond with the more dense concentration
near the bottom.

This denitrification method was initially proposed by Dr. Perry L. McCarty.
In order to determine  if this process would work under field conditions,
3-ft.  (0.91 tn) diameter pipes, 6 to 11 feet deep (1.83 m to 3.35 m) were
installed to simulate deep ponds.  The simulated ponds demonstrated that
this process of denitrification would work under field conditions.  Based
on these results, two deep ponds were constructed at the Center.  One pond
is 60  feet (18.3 m) by 200 feet (61.0 m); the other 50 feet square (15.2 m).
Both ponds are approximately 14 feet deep (4.28 m).  The larger pond is
covered with a floating styrofoam material to reduce algal growth and
surface reaeration.

In August 1968, pilot-scale studies began using these two ponds.  A
nitrate-nitrogen removal of 90 percent has been achieved in the larger pond
at a ten day detention time.  The smaller pond has experienced hydraulic
short-circuiting, thus reducing the nitrogen removal efficiency.  These
problems have now been corrected and the pond is now operating.  Preliminary
data this winter indicate that an increase in the detention time may be
necessary as the water temperature drops.

Filter Denitrification

This method is very similar to the deep pond process except an aggregate
bed is used.  An advantage of this method over the pond system is that the
surface area to which the organisms can attach themselves is greatly
increased, thus producing a greater concentration of bacteria.  Also since
the bacteria have something to which they can attach themselves, the waste-
water  can be passed by the bacteria at a higher velocity without washing
them out as would happen in a deep pond where the bacteria are "free-floating."
Because of these advantages, the nitrate-nitrogen is reduced to nitrogen
gas more quickly than in deep ponds.

All filter denitrification studies at the Firebaugh Center have been
performed in upflow columns with a 6-ft. (1.83 m) media depth.  Methanol
is added to the wastewater just before it enters the bottom of the filter.
Initial filter studies were accomplished using 4-inch (10.2 cm) diameter
pipes.  These small pipes demonstrated that this process would work well
under  field conditions.  Based on these results 18-inch (45.7 cm) and 36-inch
(91.4  cm) diameter filters were installed.

The major variables investigated have been detention time and filter
media.  Some of the various media evaluated include sand, activated carbon,
gravel, volcanic cinders,  coal and a commercially produced trickling filter

media.  The most satisfactory media has been one-inch (2.54 cm) diameter
gravel.  Smaller diameter media were investigated but after several
months of operation the head loss through the filters was greater than
experienced in the one-inch  (2.54 cm) diameter media.  The majority
of the head loss through the filter is caused by the dense bacterial
mass within the filter.  As  the bacterial mass builds up and the head
loss increases, short-circuiting will begin to occur within the filter
thus reducing the nitrogen removal efficiency.  Some of the filters
have been operating continuously for nearly a year without requiring
cleaning due to bacterial build-up.  The head loss through these filters
has not significantly increased during this continuous period of

The detention times evaluated have been two hours, one hour, and one-
half hour.  All filters have a minimum of quarter point sample ports
so nitrogen removal profiles can be studied.  At all detention times
studied greater than 90 percent removal of the 20 milligrams per liter
(mg/1) of nitrate-nitrogen has been achieved.  However, during periods
when the influent wastewater is below 10°C, the removal efficiency
of the filters is reduced.   Studies are presently underway to try to
better define the temperature effect on the bacterial denitrification
system.  From data collected thus far, it appears that a filter using
one-inch (2.54 cm) diameter  aggregate at a one-hour detention time will
be effective in removing 90  percent of the 20 mg/1 of influent nitrate-
nitrogen at temperatures above 12°C.

A  larger filter, 10 feet  (3.0 m) square, has recently been constructed
at the Center.  This filter, filled with one-inch  (2.54 cm) diameter
aggregate, will be used to evaluate hydraulic characteristics of large
upflow filters.

Comparison of Biological Denitrification Methods

As mentioned earlier, estimated flows from the San Joaquin Valley will
approach 700 million gallons per day  (2.65 x  10  cu m/day) after the
year  2000.

The  land requirements  for the three denitrification methods will vary
greatly, based on present knowledge.  The algae  stripping method will
require about 9,000 acres  (3645 ha) of land,  pond denitrification
about  1,100 acres  (445 ha) and filter denitrification about 150 acres
 (60.8 ha).

At 700 mgd  (2.65 x  106 cu m/day) the  algae stripping method will produce
approximately 450  tons  (410  metric  tons) per  day of dried algae.  The
bacterial  denitrification  systems  produce no  usable by-product.

Initial estimates  project  the costs of these  three biological  systems
nearly the  same—around $10  per  acre  foot  ($8.10/1000 cu m), or $25
to $30 per million  gallons  ($6.60  to  $7.90 per million  1).  Recent
reduction  in  the cost  of methanol  may  further reduce the cost  of

bacterial denitrification.  Also the original cost for the algae
stripping method did not include any return for the dried algae which
may also reduce the cost of this system.

The California Department of Water Resources cost estimates for the
formerly planned Master Drain are about $110 million for Western Delta
Area discharge, and about $250 million for direct ocean disposal.
At a treatment cost of $10 per acre foot ($8.10/1000 cu m) the capitalized
cost of conveyance, treatment, and discharge into the Western Delta
is about two-thirds the cost of direct ocean disposal.

Our objective at the Interagency Agricultural Waste Water Treatment
Center is to develop an economically feasible method of removing the
nitrogen from the agricultural wastewaters of the Valley.  In order
that construction of the wastewater disposal drain can continue as
scheduled, we must have the answer by January 1970.  We are actively
refining the nitrogen removal systems so accurate economic evaluation
can be made by that date.

                           COLORADO RIVER BASIN

                    Gary N. Dietrich and L. Russell Freeman —
The Federal Water Pollution Control Act, as amended, authorizes the
establishment of water quality standards for interstate waters.  These
standards are to provide for the preservation and enhancement of water
quality and the protection of present and potential water uses.  The
Act gives the States the opportunity to develop and adopt the standards
and submit them to the Secretary of the Interior for his approval and
adoption as Federal standards.  Where he finds the State standards
unacceptable, the Secretary is empowered to promulgate Federal standards.
State enforcement of standards is encouraged; however, Federal enforce-
ment is possible.  All but one of the States, the District of Columbia,
Puerto Rico, the Virgin Islands and Guam have adopted standards, and
these have been fully or partially approved as Federal standards.

This paper discusses salinity criteria  for the Colorado River Basin.
Although salinity criteria ordinarily would be included in the water
quality standards, the seven States of  the Colorado River Basin concluded,
after careful consideration, that sufficient information was not available
to develop and implement such criteria.  The Secretary of the Interior
concurred  in this decision and further  determined that studies should
be undertaken to develop the basis for  formulating equitable, workable
and enforceable salinity criteria.  Consequently, the water quality
standards  adopted and approved for the  Colorado River and the other
interstate waters of the Basin are void of mineral quality criteria,
or salinity  criteria as they are commonly called.  The task of
formulating  such criteria has been deferred pending the development of
the capacity and knowledge to perform  this task.

Salinity criteria present some significant and even serious implications
for irrigated agriculture, hence the reason  for  selecting this topic
for discussion.  It is  to be noted that other aspects of water quality
standards  -- sediment and turbidity  criteria and nutrient, pesticide
and even temperature criteria -- also  apply  to and  affect irrigated
agriculture.  However,  to enable  an adequate treatment of the salinity
criteria issue,  a discussion  of  these  other  aspects is not included
in this paper.

Salinity is  the most  serious water quality problem  in the Colorado River
Basin.  Like many  streams  in  the  arid  West,  the  Colorado River displays
a progressive  increase  in  salinity between  its headwaters and  mouth.
      —'  Respectively,  at the time of presentation,  Deputy Director,
 Division of Technical  Support and Deputy Director,  Colorado River-
 Bonneville Basins Office, Federal Water Pollution Control Administration.

Currently, the average salinity concentrations in the Lower Colorado
River range from approximately 750 mg/1 at Hoover Dam to about 850
mg/1 at Imperial Dam.  Approximately 47 percent of these concentrations
derive from natural causes -- mineral springs and diffused pick-up
of salts by surface drainage -- and the remainder results from man's
development and use of the Basin's water resources.  Planned and
proposed development of the water resources will further increase the
existing levels of salinity, and, by the year 2010, average salinity
concentrations are expected to be 990 mg/1 at Hoover Dam and 1220 mg/1
at Imperial Dam.

Generally, as salinity concentrations increase above 500 mg/1, the value
of water begins to diminish and the costs associated with its use begin
to increase.  Increasing costs are incurred in water softening or
alternately, in the form of costs of corrosion, fabric wear and increased
use of detergents.  They also include diminished crop yields, the
inability to grow certain high-value crops and the need for greater
amounts of leaching water to maintain salt balance in the root zone.
Because of such costs, increasing salinity levels in the Lower Colorado
River constitute a significant water quality problem.  In fact, the
economic costs presently suffered by the water users of the lower
Colorado River amount to several millions of dollars annually, and
these will increase to over 15 million dollars per year by 2010 if
the predictions of future increases in salinity hold true.

The problem faced in water quality management in the Colorado River
Basin is one of improving existing mineral quality, or at least,
minimizing future salinity increases, particularly in the Lower Colorado
River where the effects of degraded mineral quality are most severe
and most costly.  On first examination, salinity criteria appear ideally
suited for meeting either of these purposes.  Such criteria would provide
concentration limits for total amount of salt and its constituents at
each of some dozen or two dozen points throughout the river system and
would set forth a plan of implementation and enforcement delineating
how and where sources of man-caused salinity would be controlled to
achieve compliance with these limits.  Unfortunately, neither the
development nor the implementation of such criteria would be simple.
In fact, these criteria could significantly interfere with the development
and consumptive use of water for irrigated agriculture and other purposes.

The confounding problem in developing salinity criteria for the Colorado
River Basin, where irrigation is the principal source of man-caused
salinity, results from the consumptive use of water in crop production.
From 50 to 70 percent of the water applied in irrigation is consumed
by evapotranspiration.  The remaining 30 to 50 percent returns to the
river system as irrigation return flow.  This return flow usually contains
all of the salt load of the applied water, but in a smaller volume of
water.   It may also pick up additional salts in the process of returning
to the stream.   Accordingly, as water passes through an irrigation
cycle,  its salinity concentrations are increased.   Even if there were
no salt pick-up by irrigation return drainage and no non-beneficial
evaporative losses of water, irrigation would unavoidably increase

salinity.  To avoid this salinity increase would require nothing less
than a reduction of consumptive use, presuming that there exists no
economically feasible means of removing salts from irrigation return
flow.  Such implementation of salinity criteria would severely conflict
with existing water rights, interstate compacts and international
agreements which have established the division and allocation of the
Basin's water resources.  Two examples will serve to illustrate this

Suppose  that salinity criteria based on existing salinity levels were
to be set at several points along the lengths of the Colorado River
and its major tributaries.  Unless the River's salt load could be reduced
markedly, compliance with these criteria would lock-in present patterns
of water use by precluding any additional consumptive use of the
Basin's waters.  Future development of irrigated lands, as now planned
and proposed, would have to be halted and full use of the waters
allocated by compact to the Upper Basin States would have to be sacrificed.
In effect, these criteria would abrogate undeveloped water rights and
thereby  would impose restrictions not commonly supposed to be the
function of water quality standards.

On the other hand, it would be possible to establish salinity criteria
throughout the Basin which would be based on existing salinity concentrations
plus allowances for future increases of salinity expected to result
from future consumptive use.  However inviting this possibility might
seem, it must be noted  that these criteria would fix the distribution
of future consumptive uses and thereby would predetermine the future
development of irrigation and other water uses.  Accordingly, the setting
of these criteria would be impractical to the degree that future water
use cannot or should not be predetermined.  Furthermore, it is  far  from
certain  that such criteria can be established without imposing  inequities,
even though  their principal objective would be the achievement  of an
equitable pattern of consumptive uses compatible with prevailing water
rights and compact divisions of water.  The principal deficiency of
these criteria, however, would be their failing  to protect and  preserve
present  water quality.  This would  be of  greatest concern to current
water users  of the Lower Colorado River who would suffer significant
degradation  of their water supply because of  the built-in allowances
for  future  increase  in  salinity.

These difficulties  in developing  salinity criteria do not mean  that  such
criteria cannot be derived or  are  inappropriate  for  controlling mineral
quality.  It  is  technically possible  to develop  basin-wide salinity
criteria for  the  Colorado  River  Basin.  Sufficient data on historical
stream  flows  and  mineral  quality, on  flow-quality relationships and
on expected  stream flows  and  quality  under various  levels of planned
or proposed  water resource development  are available for this purpose.
Accordingly,  salinity criteria to preserve existing  mineral quality
with or  without  allowances  for various  patterns  of  future development
can  be  formulated.   The problem is  not  so much in  this  initial  step of
establishing criteria,  except for the difficulties  in formulating

 equitable  criteria,  as  in  the  subsequent  step  of  implementing  the
 criteria.  With  respect  to the appropriateness of salinity  criteria,  it
 must  be  recognized  that  their  purpose  is  the protection  of  legitimate
 water uses,  including irrigation  uses.  That the  protection of existing
 water uses in  the Lower  Basin  requires  a  restriction  of  upstream water
 uses  is  less a fault of  these  criteria  than the limitations of nature.
 If public  policy is  to preserve presently developed water uses, this
 might require  some  restriction of new water uses,  regardless of whether
 salinity criteria or other regulatory devices  are  employed  to  effect
 this  policy.   In this sense, salinity criteria are nothing  but tools
 to implement public  policy and on this  point an examination of how
 such  criteria  could  be administered and what implications they would
 have  for irrigated  agriculture is in order.

 Although there are  a number of alternative measures which are  discussed
 later, there are only two  direct  approaches to implementing salinity
 criteria within  the  Colorado River Basin:  the  regulation of consumptive
 water uses and the desalination of waters whose salinity has been con-
 centrated  by consumptive use.  To implement salinity  criteria  through
 the regulation of consumptive  uses would  require  adding quality to
 quantity in determining water  rights and  interstate divisions  of water.
 The essential  feature of this  approach would be the reservation of
 portions of river flows  for the carriage  of salt  loads.  This water
 would remain in  the  river  system  and would not  be  allocated  to  con-
 sumptive use.  River flows in  excess of salt carrying flows would be
 available  for  division among the  States and allocation to water users.
 It is  immediately apparent that such an approach would require considerable
 modification of  the  institutional devices and  procedures currently
 employed to administer western water laws.  Even so,  these modifications
 would  be insignificant compared with the changes that would have to be
 made  in  perfected water rights and interstate divisions of water.
 In most  cases, salinity criteria would restrict rights to consumptive
 water  use  much more  severely than existing water rights which are
 wholly based on  a division of  available quantities of water.  The
 following  example will illustrate this point.

 At Hoover  Dam, the Colorado River presently carries  an average of
 10.9 million tons of salt per year.   If a salinity criterion of 800 mg/1
 total  dissolved  solids were to be set at the Dam,   an average annual
 flow  of  about  10 million acre-feet would be required to carry this salt
 load.  Present average annual  flows at Hoover Dam are about 11 million
 acre-feet.   Consequently, a salinity criterion of  800 mg/1 would permit
 only  1 million acre-feet per year of additional upstream consumptive
 use.    This would deprive the Upper Basin of a substantial part of its
 average annual allocation of 7.5 million acre-feet, as provided by
 the Colorado River Compact, and would necessitate  considerable readjust-
ment  of prevailing interstate divisions of water and of existing water
 rights within  the Basin States. At the present time, for the reasons
 illustrated in the foregoing example,  the employment of consumptive
use restrictions to implement salinity criteria does not appear promising.
Nevertheless, eventual and perhaps partial use of such restrictions

can and should be foreseen, whether these are specifically for the
purpose of implementing salinity criteria or are incidental to other
means of managing the Basin's water resource.  A case in point is the
following.  If it is assumed that 3000 mg/1 total dissolved solids is
the practical limit for usable water and that the last user on the
Colorado River is to enjoy water quality not exceeding this limit, then
to carry the River's 10.9 million tons per year salt load at this last
point of use will require an annual average river flow of about 2.4
million acre-feet.  This would be water reserved from upstream consumptive
use for allocation to salt carriage and, in a sense, for wasting into
the ocean or into the Salton Sea.  As this demonstrates, it is virtually
impossible to use the entire water resource of the Basin for consumptive
use if the last users are to enjoy any reasonable levels of mineral
quality.  Consequently, restrictions on consumptive use for the reser-
vation of salt carrying flows are a practical necessity.

The other direct approach to implementing salinity criteria would involve
the desalting of wastes from consumptive use operations, including
irrigated agriculture.  A percentage of the salt proportional to the
percentage of the water consumptively used would be removed so that
the water returned to the river  system would have the same salinity
concentration as that withdrawn.  Such an approach, if perfected, would
permit consumptive use of nearly all'of the water resource  (some water
would be  lost in brine disposal) and would eliminate the need to allocate
large river  flows for carriage of salt load.  Furthermore, this approach
would put salinity control on the same basis as the control of other
pollutants,  by requiring the removal of salts as necessary to compensate
for  loss  of  water in the water-use cycle.  Unfortunately, this desalting
approach  is  presently encumbered by  some severe economic and technical
constraints.  Foremost among these is the high  cost of desalting water.
Several recent studies conclude  that large-scale desalting, usually
combined  with thermal power generation, for  the production of waters
for  direct use will be economically  feasible  in the near future  (1980  to
2000).  However,  the approach just described would  require  small-to-
medium  scale desalting plants for waste water treatment, and it  is
doubtful  that such  small scale plants will be economically  feasible
in the  near  future.  The technical problems  include the necessity  of
disposing of brines  (these  cannot be reintroduced  into  the  river  system
and  must  be  disposed of  in closed basins, deep  geological  formations
or the  ocean) and  the  necessity  of providing drainage  systems  for  all
irrigated lands  in  order to  collect  return  flows  for  treatment.
Notwithstanding  these  several  liabilities,  the  desalting approach  may
hold some promise  for  the  future.

Recognizing  the  problems  in formulating and  implementing  salinity
criteria, it seems  appropriate  to  turn  attention  to other  approaches
 to salinity  contol  --  approaches which  do  not necessarily  depend on
 the establishment  of criteria.   Currently,  there  appears  to be three
 such approaches:  the abatement  of  salinity at selected  sources including
natural sources,  the augmentation of river flows  and  the  desalination
of waters for use.   Measures to abate  salinity at selected sources would

seek  to  control  salinity  arising  from causes  other  than beneficial
consumptive  use.  About 47 percent  of the  current levels  of  salinity
at Hoover  Dam derive  from natural causes  -- the dissolution  of  the
salts in soils and  geologic  formations by  natural surface and subsurface
flows.   In some  cases, these  causes  of salt loading can be controlled
by such  methods  as  the plugging or  suppression of mineral springs;
the diversion of stream flows around salt  domes and other areas  of
substantial  salt  pick-up; and the diversion of highly mineralized
surface  flows into  closed areas where they can be disposed of or used
for salt-tolerant uses.   These several measures would eliminate  a part
of the salt  load  presently reaching  the Colorado River and thereby would
permanently  reduce  salinity concentrations in the River.

Another important cause of salinity  is the  salt pick-up by irrigation
return flow  as it percolates  through the soils enroute from  the  irrigated
land  to  the  river system.  This salt pickup accounts for  about  26
percent  of the salinity presently measured at Hoover Dam.  This  salt
load  can be  significantly reduced by (1) eliminating excess  drainage
(over and  above  that  required for leaching in maintaining salt balance
in the root  zone);  (2) the lining of canals and other conveyance
channels;  (3) intercepting drainage  at the bottom of the  root zone and
conveying  it  to  the river system, thus short-stopping unnecessary
subsurface travel and (4) selecting  for new irrigation only  those lands
which are  underlain by low salinity  soils.  These measures would
reduce man's  contribution of salt input into the river system and
thereby  would serve to permanently reduce  salinity.  Preliminary
estimates  indicate  that a program of selected salinity source control
can achieve  salinity reductions of up to 300 mg/1 at Hoover  Dam.  Such
a program would depend, in large measure,  on irrigated agriculture.
The provision of  structural control  measures such as drains  and canal
lining and the institution of improved water management practices would
be necessary  to the full success of  the program.   Studies indicate,
considering  the potential multiple benefits of such features, that
there is ample economic justification for  the development of such measures

Augmentation  of Colorado River flows would involve  interbasin importation
of water, weather modification,  water salvage or a  combination of these
measures.  Although these means are  currently being proposed (and
studied  except for  interbasin importation) for the  primary purpose of
meeting  expected future water shortages,  they would provide  significant
water quality benefits.   For example, 2.5 million acre-feet  per year
of 300 mg/1 water delivered at Hoover Dam would reduce present levels
of salinity by about  75 mg/1.  Consequently,  flow augmentation is also
an attractive means for improving the mineral quality of  the Colorado

Finally, the desalting of water for  direct use is an approach that may
be necessary  to mitigate the consequences  of uncontrolled or only
partially controlled salinity; that  is, for providing acceptable water
supplies to replace those that are over mineralized.  In addition,  of
course, desalting also can serve to extend the Basin's water supply.

Large-scale desalting combined with electric power generation is being
studied.  Preliminary results indicate that this means of producing
high quality water may be economically feasible in the foreseeable
future  (1980 to 2000).  Certainly, desalting is a potential alternative
to be considered in solving the salinity problem of the Colorado River

In conclusion, it is foreseen that the establishment of salinity criteria
for the Colorado River Basin will be difficult and may be a long time
in coming.  A promising alternate and interim approach would be the
study and implementation of the three means of control just described.
The abatement of the increasing salinity of the Colorado River system
cannot  afford further deferral particularly when the techniques to
achieve such abatement seem close at hand.  A combination of salinity-
source  abatement, flow augmentation and desalination can accomplish
immediate and needed results.  And, if and when salinity criteria
can be  and are established, these measurers can be easily and readily
factored  into whatever devices are developed to implement and enforce
these criteria.

                        WATERS IN ARID REGIONS


          H. B. Peterson, A. A. Bishop, and J. P. Law, Jr. —'
Historically, the users of irrigation water have been more concerned
with quantity rather than the quality being used.  Now they must also
be concerned with the quality of water being used as well as that
which returns to the supply to be reused for other purposes or for
irrigation.  We no longer have enough water to pollute and discard.

A hydrologic unit (river system with its drainage area and groundwater
basin, etc., and with its animal, plants, minerals, and people) can
be considered as a self-contained, hydro-pollution-purifying system.
The state of the system without man in it, if we can imagine such,
is natural and produces changes as a result of the dynamism within
it-  In this natural or pristine state, changes  in climate, vegetation,
geologic erosion, animal inhabitants, etc., are  dynamic, having an
impact on the quality of the environment and resulting pollution in the
natural drainage from the area.  The introduction of man into the system
with his power to create major changes and to introduce new or additional
pollution or treatment vectors in the waters of  the system make it
imperative that the system be considered in its  entirety and not from
the standpoint of a single use or source of pollution.  Man superimposes
on the system, cities, transportation facilities, agriculture, irrigation
and drainage facilities, manufacturing plants, mining, timber harvesting,
range use, recreation, and other changes too numerous to mention.  The
interactions of man, and the changes he produces, within the hydrologic
system is the major concern of this paper, particularly with respect
to irrigation and irrigation return flow.

Those who live in arid regions are intensely aware of the keen
competition  for a limited water supply.  The climate  is conducive to
high evapotranspiration losses and a minimum of  natural leaching.  For
intensive crop production, irrigation is necessary in arid regions while
it is used only to  supplement rainfall in more humid  areas.  Water
quality requirements for agriculture vary considerably with soils, crops,
and climate.  The adverse effects of low quality on soils and plant
growth are related  to the frequency and amount of water applied.  Problems
associated with deteriorating water quality are, therefore, more
numerous and acute  in arid and semiarid areas where the water require-
ments of the growing crop are satisfied almost entirely by irrigation.
      —  Professor  and  Head,  Dept.  of Agricultural  and  Irrigation
Engineering,  Utah State University,  Logan;  and  Research Soil  Scientist,
Robert  S.  Kerr Water  Research Center, USDI-FWPCA, Ada,  Okla.,  respectively.

           Sources and Types of Pollution Affecting Water Quality

In the hydrologic cycle,  it is natural for the pollution of a river
system to increase as the water moves toward the ocean where it is
purified by distillation  and returned to the watershed.  Enroute,
considerable purification takes place in the streams by oxidation and
biological degradation.  Pollutants come from many sources before,
during, and after irrigation.  They come from the animals; soils,
both irrigated and non-irrigated; fertilizers; pesticides; as well
as from industrial and municipal wastes.  Some pollution is natural,
such as from mineral springs, lightning fixed nitrogen, etc.  Even
a pristine river will show considerable quality change between its
source and the estuary.  As indicated in Figure 1, the activities
of man to protect or improve the quality of water are counter forces
against natural pollution and man's normal tendency to pollute.

Our major concern, which  is irrigation return flow, may be subject
to augmentation and further pollution from sources not connected
with irrigation; that is, precipitation, groundwater seepage, surface
runoff from urban areas, highways, and non-agricultural lands and
discharges from municipal and industrial sources which may commingle
with irrigation return flow.  Quantity, quality, nature, and extent
of pollution from commingled waters have not been isolated or evaluated.
This will be difficult, but is essential in order to properly assess
the quality and pollution role of each water use affecting the total
water supply.

Natural Pollution

Of the many possible natural pollutants, salts and sediments are
likely of greatest concern to all users; however,  under certain
conditions,  animal waste, plant nutrient,  and toxic elements may
become equally important.  To irrigation agriculture and subsequent
users of return flow, salt and silt create the most difficult problems.

gait and sediments.   Of the potential pollutants identified that may
enter into the water supplies, the one of greatest concern to irriga-
tion is salinity which is a natural product of geologic weathering.
It is released from contemporary weathering,  mineral springs, and
seepage from areas of salt accumulation.  Pillsbury (1) developed a
relationship between water production and salt yield on several western
watersheds.   The salt production on streams varied from 0.1 ton per
acre foot (a.f.) on streams producing 1,000 a.f./sq. mile to over
5 tons/a.f.  on streams producing only 1 a.f./sq. mile.  The Bureau
of Reclamation has an active program to evaluate the quality of water
of several river basins.  Some of the results are  indicative of the
amount of salt loading resulting from natural sources, irrigation,
and others (2,3,4).   As indicated in Table 1, the  salt from natural
sources exceeds, in this instance, that from irrigation.

                          CLEAN WATER


             CLEAN WATER ACT
             WATER TREATMENT
                       DIRTY WATER — OCEAN
         Figure 1.  Forces of pollution with  counter  forces,

                                  TABLE 1
                     COLORADO RIVER AT HOOVER DAM (5)
                 Sources                      Total Dissolved Solids
       Diffuse Sources                                 274
       Point Sources (mineral springs,
          wells, etc.)                                  69


       Consumption                                      88
       Leaching                                        165

   Municipal and Industrial Sources                     10

   Water Exports                                        22

   Evaporation and Phreatophytes                        97

There is little concrete information on the amount of sediment resulting
from wind and water erosion.  (Erosion that would take place without
man's influence.)  As previously noted, climate is a factor responsible
for some of the salinity and sodium problems found in the arid irrigated
areas of the West.  It can, likewise, have effects on other pollution.
The amount and intensity of precipitation can influence the amount of
erosion and the accompanying sediment load of the flow.  Many of the
watersheds are relatively unprotected by vegetative cover and are,
therefore, subjected to considerable erosion when moisture falls on the
land during high intensity storms.  It is evident, however, that the
sediment load resulting from natural erosion is much more sporadic than
the salt load.  In many of our arid basins only a small percentage of
the land surface is irrigated having a large watershed acreage to
produce salt and sediment loading of the river system.  Van Denburgh
and Feth (6) estimated the annual solute erosion in 11 important river
basins.  The wide range in tonnage was attributed to a complex of
causes, among which were differences in geology, climatic environment,
and the activities of man.  Rates of solute removal were highest in
areas of abundant precipitation and runoff, in contrast to rates of
sediment removal, which are characteristically highest in basins subject
to 10-15 inches effective annual precipitation.  Storage dams on most
river systems greatly modify the sediment problems.


Nutrients, toxic elements, and organics.  Nitrogen is added to the
system as a result of fixation by lightning and microorganisms, leaching
from nitrate deposits, and the mineralization of organic matter.
Phosphorus enters the system as a result of mineralization or organic
matter, such as non-agricultural plant and animal wastes, release from
sediments, and solution of natural phosphate minerals.  Toxic elements,
such as boron, enter the supply from natural deposits, usually by way
of mineral spring waters.

Agricultural Pollution

The emphasis of the current discussion is on the effects of irrigation
on water quality.  As such, it is not possible to completely separate
the pollution attributed to irrigation agriculture from the non-irrigated.
It is also worthwhile to remember that while increasing salt concentration,
the irrigation process may remove other pollutants introduced into the
water supply from cities, farms, and industries.  For example, nutrients
and organic wastes deposited on agricultural land with irrigation water
may be used by the crop, fixed by the soil, or degraded, so they are
not contained in the irrigation return flow.

Salts and sediments.  Salt pollution from agriculture is limited almost
entirely to irrigated agriculture.  Irrigation implies the extraction
of almost pure water by  the plants from the water supply with a resulting
inevitable concentration of those dissolved solids which are characteristic
of all natural water supplies.  Whereas other uses add something to  the
water, irrigation basically removes water, thereby concentrating the
salts.  Irrigation may also add substances by leaching natural  salts or
other materials  from the soil or washing them from the surface.  Irrigation
return flow is a mechanism, as illustrated in Figure  2,  by which the
concentrated  salts and other  substances are conveyed  from  irrigated
agricultural  lands to the common  stream or underground supply.   It includes
bypass water, seepage, deep percolation losses,  and  tailwater  runoff.
The pollution effects of irrigation are different for each specific
area  or condition and depend  on the concentration in the irrigation  water,
the proportion of the water leaching  through  the soils  to  that  applied,
the number of times  the  water is  reused, and  the amount  of leaching
from  areas having residual salts.  Salty groundwater and salt  bearing
shales serve  as  an abundant source of salt  that  may  be  loaded  into the
system both directly  and indirectly by  irrigation.   It  is  this loading
potential  that makes  it  most  difficult  to  estimate  the  salt  concentration
in  the drainage  water  and  the amount  of salt  loading that  may  be expected
along a river  system.   This  is  also  the reason why  a salt  balance  for
a given  area  is  of  little  value  as evident by the equation:

                                                Application of fertilizers,
                                                herbicides, and pesticides
                                                to soil or plants
               of relative  pure.
                     water      |
               Concentration of
               salts in the soil
               solution due to
                                                               pure water)
                                      Nutrients etc.
                                      used by plants^
Fertilizers, wastes,
herbicides, etc.,
digested, degraded, or
precipitated within the
soil  profile
   Surface runoff with
   sediment, residues,
   and  dissolved
W  t
 . Total^
 / water
i added
                            *      *
                                               Irrigation water
                                               with various
                                               amounts of
                                                             Deep percolation
                                                             and drainage
                                                          Groundwater recharge
       Figure 2.
Effect  of  the water-plant-soil complex  on  the quantity  and quality of
irrigation return flows.
                        Return flow  from agricultural lands
                        with salts,  residues, pesticides and
                        other pollutants

                    S   +S+S-S    - S   =0
                     iw    w    r    ppt    dw


                    S      = salt In the irrigation water

                    S      = salt from contemporary weathering

                    S      = residual salts

                    S      = salt precipitated

                    S      = salt in the drainage water

There may be a balance for a basin, but much of the outgoing salt can
come  from the reserve rather than from the soil being irrigated.

The concentration of the salt in the soil solution will usually be
in the range of 4-10 times the concentration of the irrigation water;  and
hence, the  solution draining from the soil profile may be much higher
in salt content than the water applied.  Where the drainage from the
root  zone is impeded by a high water table, the concentration of the soil
solution may be many times the concentration of the irrigation water.
Fortunately, the concentration of salt in many irrigation waters is so
low that the leachate under normal  irrigation practice is much less
concentrated than theoretically possible, and, when return to the
stream or the groundwater body, the effect on the quality of the resulting
water is not serious.  The average  increase in concentration in return
flow  is usually in the range of 2.5 to 7  times that of the source water.
The scope of the problem of return  flow  is, therefore, limited from a
practical standpoint to those areas and  conditions where water quality
becomes degraded to  a point where it constitutes  a nuisance, a hazard,
or is of no value for further use.

Irrigated soils of the United States are scattered throughout, but
the major areas are  in the  17 western  states.  Within  these, the areas
most  adversely affected by  salt  in  the  irrigation return flow are  those
in the  lower reaches of the  larger  river systems  of  southwestern United
States; those  areas  in the Lower Basin of the Colorado River, the  Gila
and Salt Rivers of Arizona,  the Rio Grande  in New Mexico and Texas, the
San Joaquin River in California, and similar  streams.  In  all of these
river basins,  there  is a progressive deterioration  in  water  quality as
 it  flows downstream.

Nutrients and animal wastes.  To understand the problem of pollution
of waters with plant nutrients  from  fertilizers,  it  is necessary  to
understand the factors which affect  the forms and solubilities of the
plant nutrients and the manner  in which these are transported.  The
nutrients of major concern as pollutants are nitrogen and phosphorus.
Nitrate in the drainage water can originate from rain, dust, soil,
organic matter, manures, an accumulation in the soils prior to irrigation,
fixed by microorganisms, fertilizers, and from the wastes in urban
and industrial runoff.  It is removed from the soils by crops, de-
nitrification, and in drainage waters.  It is, therefore, difficult
to determine the source of the nitrate in drainage waters.

The presence of plant nutrients in surface water is often attributed
to a seemingly large tonnage of fertilizers applied to the land for
maximum crop production.  On much of the land, the amount of fertilizer
applied is less than that used by the crop.  A low average application,
however, does not exclude the possibility of excessive amounts being
used on a portion of the acreage.  For some high value crops, such
as celery, where the common practice is to make heavy applications of
fertilizers, particularly nitrogen, coupled with frequent irrigation,
it is likely that considerable nitrate may be leached with the excess
water and appear in the waters of the drainage system.  Doneen(8)
concluded from a careful study in the San Joaquin Valley of California
that in one field receiving heavy application of fertilizer a large
portion of the nitrate in the drainage water was from the fertilizer.
In two other fields recently drained, he could not come to the same
conclusion because nitrates had been accumulating in the subsoil  and
groundwater for a long period of time.  It is estimated that from
combined sources, the nitrate-nitrogen content of the water in the
San Luis drain is expected to be of the magnitude of 20 mg/1 (9).

Phosphate fertilizers can increase the phosphorus content of drainage
water in several ways.  Percolating water passing through a heavily
fertilized sandy soil low in fixing capacity will carry soluble
phosphorus into the drains.  Fertilizers applied to the surface of
soils tend to stay near the surface and saturate the "fixing" sites.
When the fertile surface particles are eroded by wind or surface  runoff,
the phosphorus is carried with the sediments into the water system.
There it equilibrates with the phosphorus in the water and may increase
the concentration in solution unless the content of the water is  at
or above the equilibrium concentration.  Biggar and Corey (10) speculate
that runoff water in contact with fertile surface soils can pick  up
soluble phosphorus as it moves over the surface of the land, and  the
concentration of the runoff water might range up to a few tenths  of a
mg/1.  Phosphate fertilizer can also have a more indirect effect.
It can stimulate plant growth, and then parts of the plant,  such  as
dried leaves, can be carried by wind or water into the drainage water
where the plant material is mineralized by microorganisms, with the
resulting accumulation of soluble orthophosphate in the water.

Johnston et al.  (11) studied N and P losses In tile drainage effluents
from H number of tile drainage systems in irrigated areas in the San
Joaquin Valley of California.  A number of cropping practices, with
crops (cotton, alfalfa, rice), fertilizers and irrigation water
applications as variables were involved in the study.  Initial tile
effluent analysis in a previously unirrigated noncropped area showed
an N concentration of 1 mg/1.  Another system that had been cropped
to alfalfa and had a low discharge over the period of a year yielded
a range of N between 2.0 and 14.3 mg/1.  On systems where high rates
of N fertilizer were applied, the concentrations ranged up to 62.4 mg/1.
In the systems reported, the range of concentrations of nitrates
went from  1.8 to 62.4 mg/1 with a weighted average of 25.1.

Both nitrogen and phosphorus can be carried directly into the surface
drains with the tailwater from fields where the fertilizer is being
applied in the irrigation water.  Another likely source of nutrient
pollution  is  the animal wastes in the runoff from pastures and feeding
lot operations being included in drainage waters.  Pollution can also
come from  non-irrigated agricultural  land.  The runoff water would be
expected to contain very small amounts of salts, and other pollutant
loading would be similar to  the runoff from irrigated land.  Erosion,
with the resulting  sediment  load, plant nutrients, and pesticides would
be sporadic and greatly influenced by the intensity  of precipitation.

The rapid  growth of  large animal-feeding operations  has resulted
in a tremendous increase in  the potential pollution  hazard  from domestic
animal wastes.  A recent report  (12)  states: "Animal wastes  in this
country probably exceed wastes from any other segment of  our  agricultural-
industrial-commercial-domestic complex."  The Department  of Agriculture  (13)
has estimated that  over  1.5  billion tons of animal wastes are produced
annually,  one-third of which is  liquid, and as much  as  50 percent
coming  from  concentrated production operations.  From the USDA
population equivalent  values,  it  is evident that a  feedlot operation
with  10,000  cattle  will  produce wastes equivalent  to a  city of  164,000
people.  A city  of  this  size will  use over  8 million gallons  of water
per  day to carry  its wastes  while  the feedlot  seldom uses large
quantities of water to carry the wastes.   Untreated  municipal sewage
may  have  a biochemical oxygen demand  (BOD)  of  about  100 to 400 mg/1.
Runoff  from cattle  feedlots  produced  by  rainfall  is  a very high
 strength  organic  waste and  may have a BOD  content  as high as 10,000 mg/1
 (13,14)  depending on rainfall amount  and  intensity,  antecedent  moisture
 conditions,  slope and  surface conditions  of lot,  degree of deterioration
 of  wastes, and other factors.  It has been further demonstrated  that
 feedlot runoff is a source  of high concentrations  of bacteria normally
 considered as indices  of sanitary quality (14).   Other  pollutants
 arising from animal wastes  are the nutrient compounds  of nitrogen  and
 phosphorus,  and mineral salts.  It is difficult to predict the magnitude
 of  the  pollution problem in drainage  systems induced by animal wastes.
 It  is safe to assume that there is a  considerable amount of such pollution,
 and that the drainage lines and ditches provide conveyance routes  to
 the waterways.

 Pesticides.   Pesticides are recognized potential pollutants in water.
 As with nutrients,  the origin is not restricted to agricultural usage.
 Pesticides are used in the cities, industrial areas,  in forests, as
 well as on the farmland.   They can enter the water by direct application
 from drift during application or be washed from adjacent lands adsorbed
 to the eroded sediments.   In a similar manner,  pesticides can also
 pollute the  waters  of irrigation return flow.  There  is nothing
 unique about pesticide pollution and irrigation, except perhaps where
 pesticides are used to control weeds and insects along irrigation canals
 and open drains.

 Many of the  pesticides used are sorbed chemically and physically by
 the soil particles.   Those thus sorbed are not  likely to enter subsurface
 waters.  LeGrand  (15) reporting on movement of  pesticides in soils
 suggests that it  is likely that most all pesticides in streams result
 from overland flow.   Nicholson (16) in discussing pesticide pollution
 control states:

        The two principal  sources of water pollution by
        pesticides are runoff from the land and  discharges
        of industrial  waste,  either from industries that
        manufacture  or formulate pesticides or from those
        that  use these compounds in their manufacturing processes.
        Less  important causes of pollution are (i)  activities
        designed to  control undesirable aquatic  life,  (ii) care-
        less  use of  pesticides,  and (iii) occasional accidents
        in transportation.

 Johnston et  al. (17)  analyzed  drainage effluent  from  systems located
 on irrigated land in  the  San Joaquin Valley of California.   On
 experimental areas, the insecticides  DDT,  Parathion,  and Lindane
 had been added.   Only relatively small quantities  of  chlorinated
 hydrocarbon  residues  were  found in effluent from open drains where
 both surface and  subsurface  drainage  waters were collected.  Traces
 of residue were found in  the  irrigation water applied to tile  drained
 farms.   When the  concentration  factor was  considered,  that  is,  depth
 of irrigation water applied/depth  of  drainage water removed, on a
 unit basis,  the total quantity  of  insecticide residue in tile  drainage
 effluent  did not  exceed and was generally  less than the  total  quantity
 of residue applied  in the  irrigation  water.   Tailwater,  or  surface
 runoff,  contained from 7  to  12  times  as  much  residue  as  the  applied
 water when DDT was applied to the  land and  as much  as  85  times  more
 residue  than the  irrigation water when Lindane was  applied  to  the  land.
 Relatively large  concentrations  of  residue  were  found  in the surface
 soil of  the  area  studied.

As  a generalization,  it appears  that  the chlorinated  hydrocarbons,
 such as DDT, persist  in soils  (18,19)  and do  not move  in  appreciable
concentrations through the soils and  into drainage  effluent  as  ground-
waters.  Movement  is  primarily with suspended sediment,  either  organic

or inorganic materials in streams and open drain flow.  The thiophosphates,
such as Parathion, decompose rapidly and do not persist in soils or water.

Pesticides can be transported in the air while applications are being
made and be deposited in waters remote from the area of application (20).
Wind can remove surface soil to which pesticides are adsorbed and be
deposited by rain or the settling dust.

Faulkner and Bolander (21) have found large numbers of nematodes
including plant parasites in irrigation and drainage waters.  There
is no indication yet as to the nature and magnitude of any pollution
problems that might accompany the treatment of water for the control
of nematodes.

Indirectly, pesticides may add other pollutants to soils and water.
The organic phosphorus insecticides and raiticides readily decompose
in soil and release soluble phosphorus.  Other organic pesticides are
composed of compounds containing mercury, zinc, manganese, copper,
chromium, cadmium, and tin.  When the organic compounds are decomposed,
the metal ions are released.

Municipal and Industrial Pollution

The occurrence of municipal and industrial wastewaters in water  supplies
used by irrigated agriculture may be the result of incidental discharges
into a common receiving water subsequently used for irrigation or from
direct, intentional application of  such wastewaters as a prime source
of supply.   In either case, the nature and concentration of any  constituent
that may be  considered as a potential pollutant will depend upon the
specific characteristics and origin of the wastewater; that is,  whether
(a) of purely domestic origin,  (b)  a combination of domestic and
industrial  origin, or  (c) essentially an industrial discharge.   In
addition, the characteristics of the wastewater may be ameliorated  by
the degree  of treatment and/or dilution afforded the effluent.

Municipal effluent.  Several studies of mineral increments  from
community use have been made, and an example  of data reported  is shown
in Table  2.  In  another study  (22), the  salt  pickup in the  sewage
system of  the City of Los Angeles was  635 mg/1.  The most  important
potential pollutants  in municipal wastewater  effluents affecting an
irrigation  supply would include  total  dissolved solids,  sodium,  chloride,
and boron.   Even one  use  of water could  increase the boron  content
above  the  tolerance  limits  for  some crops.  Recycle a  few  times  and the
boron  content would  almost  certainly be  too high for most  crop plants.

Industrial  wastewaters.   Characterization  of  industrial wastes  is
exceedingly difficult  for  several reasons:   (a) the numerous different
water  using and  waste  producing variety  of  industries,  (b)  the wide
range  and  spectrum  of  potential pollutants  that are  involved,  sometimes

                                   TABLE 2

                     FOR 15  CALIFORNIA COMMUNITIES  (23)
Dissolved Solids
Boron (B)
Percent Sodium (percent)
Sodium (Na)
Potassium (K)
Magnesium (CaCO-j)
Calcium (CaC03)
Total Nitrogen (N)
Phosphate (PO^)
Sulfate (304)
Chloride (Cl)
Normal Range
Domestic Sewage
varying significantly within the same industry, and  (c) the paucity of
factual  data available on  the volumes and pollutional characteristics
of many industrial wastes.  An example of important water using industries
and associated pollutional  characteristics of the wastewaters is shown
in Table 3.

Potential pollutants of industrial origin that are of particular concern
to irrigated agriculture include:  (a) total dissolved solids, sodium,
and chlorides, (b) boron, (c) heavy metals, (d) pesticides, (e) radio-
activity, and (f) numerous  organics.

Recreational Wastes

Pollution from recreational activities are probably the least delineated
of all sources.   It may not greatly influence the quality for irrigation,
but it certainly does influence the quality of water for other uses.
Man's activity is responsible for human wastes at campsites and in-
directly from summer homes.   Fishing, boating, and production of wild
game all contribute.  The building of roads, trails, homesites, etc.
expose the soil to erosion which may well be the most serious form of
pollution attributed to recreation.

                      Quality Changes from Irrigation

The only certain change in water quality caused by using water for
irrigation is the increase in the concentration of soluble salts.   How
much this change will be depends on variables at each specific location.

                               TABLE 3
Acetic acid

Citric acid

Fats, oils, grease


Hydrogen peroxide

Mineral acids

Nitro compounds
Organic acids



Tannic acid
Tartaric acid
Acetate rayon, pickle and beetroot manufacture.
Cotton and straw kiering, cotton manufacture,
mercerizing, wool scouring, laundries.
Gas and coke manufacture, chemical manufacture.
Sheep-dipping, fell mongering.
Laundries, paper mills, textile bleaching.
Plating, chrome tanning, aluminum anodizing.
Soft drinks and citrous fruit processing.
Plating, pickling, rayon manufacture.
Plating, metal cleaning, case-hardening, gas
Wool scouring, laundries, textiles, oil
Gas and coke manufacture, chemical manufacture,
fertilizer plants, transistor manufacture, metal
refining, ceramic plants, glass etching.
Manufacture of synthetic resins and penicillin.
Petrochemical and rubber factories.
Textile bleaching, rocket motor testing.
Battery manufacture, lead mining, paint
manufacture, gasoline manufacture.
Oil refining, pulp mills
Chemical manufacture, mines, Fe and Cu pickling,
DDT manufacture, brewing, textiles, photoengraving,
battery manufacture.
Explosives and chemical works.
Distilleries and fermentation plants.
Gas and coke manufacture, synthetic resin
manufacture, textiles, tanneries; tar, chemical
and dye manufacture, sheep-dipping.
Plating, photography.
Food textile, wallpaper manufacture.
Dairies, foods, sugar refining, preserves, wood
Textiles, tanneries, gas manufacture, rayon
Wood process, viscose manufacture, bleaching.
Tanning, sawmills.
Dyeing; wine, leather and chemical manufacture.
Galvanizing, plating, viscose manufacture,
rubber process.
     Reproduced by permission Butterworths.  "River Pollution.
2: Causes and Effects," Klein.

 Some  of these  are:  (a)  the  proportion  of  the water  consumed,  this  is
 dependent  on irrigation efficiency,  number  of  times the  return  is
 reused,  etc.,  (b)  the amount  of  residual  salts  leached from the soil
 profile,  (c) the amount of  salt  carried into the  drainage  system by
 seepage  from canals, storage  reservoirs,  etc.,  and  (d) the  amount  of
 salt  loading of drainage effluent  from other unidentified  sources.

 The probable changes in salinity and other  pollutants are  indicated
 in Table 4.  These  are  the  changes that are likely  to occur when water
 carrying the pollutants comes  in contact  with  soil  surface  or passes
 through  the profile.  As noted,  the  probable effects are very different
 depending  on whether or not the  water  passes through the soil and whether
 or not  the concentration is high in  the original  water.

                    Problems  of  Irrigation  Agriculture

 The users  are  concerned with  the overall  degradation of water quality
 and the presence of specific  pollutants that can  adversely  affect  the
 value of water for  irrigation  as well  as  for other  uses.  Regardless
 of the  source  of pollutants, water quality  should be evaluated  for
 potential hazards  to crops  and soils before being used.  The harmful
 effects of salt and the specific effects  of sodium, chloride, arsenic,
 boron,  and the heavy metals have been  well  established (25).

 Different pollutants have very diverse and  changing effects on  the
 value of water.  This is illustrated in Figure  3.   Salts generally
 decrease the value more or  less  in proportion to  the concentration
 increase; however,  there are broad critical ranges  where the user  is
 forced  to change the type of  crop, and then there may be a  sharper
 value decline  for  a given increment  of salt.  This  can continue  until
 at some concentration the water  can  no longer be  used for irrigation and
 must be disposed of or  treated.  At  such  a  concentration, there  is a
 change  from a  small positive value to  perhaps a large cost  depending
 upon the method of  treatment or  disposal.

 The effects of other pollutants  on value may be more nearly as  indicated
 for some specific  toxicants.  Whether  it be the  salt concentration or
 the amount of  some other pollutant that makes treatment or  disposal
 necessary, there is then an effect on  the value of  plant nutrients
which may abruptly change to a liability.    The  situation in the  San
 Joaquin Valley of California  is  an example where  there is a large cost
 for disposal of return  flow waters.  One cost is  for removal of  plant
 nutrients before the water can be discharged into San Francisco  Bay
 and the other  in the construction of the San Luis Drain to  convey the
water to the Bay (26,27).  There are,  of course,  in some instances less
 costly alternatives, such as discharge into a water fowl refuge  where it
may have some value or  directly  into a dead sea or  lake where the water
may have limited value but is not necessarily a liability.

                       TABLE 4
Sodium and
Chloride Ions
Pathogens and
Sediments and
Heavy Metals
Irrigation Return Flow
Not greatly different from sources
Relatively unchanged.
More likely a slight increase than a
decrease and highly variable.
Content may increase, but closely
correlated with erosion of fertile
Highly variable content. Surface
waters subject to polluting. Likely
associated with amount of erosion.
Variable and may increase or decrease.
Often more than in source but may
be less—highly variable.
Manures, debris, etc., likely to
Kinds and amounts are variable. Likely
to be greater than in subsurface flow.
Not greatly changed except by filtering
and oxidation effect of crops if
sprinkled .
Subsurface Drainage
Concentration increased usually 2-7 times.
Depends on amount in the supply, number of
times reused, the amount of residual salts
being removed, and the amount from non-
agricultural sources.
Both proportions and concentration likely
to increase.
Likely to decrease if the content in irri-
gation water is high and increase if amounts
are low. Greatest hazard from heavily ferti-
lized porous soils over irrigated.
Decrease if considerable in source. Not
likely to greatly increase.
A reduction in many instances. Concentra-
tions likely to be low.
Low content with a likely reduction in most
all pathogens. Other organisms may increase
or decrease.
Little or no sediment or colloidal materials
in the flow.
Most oxidizable and degradable materials to
decrease .
More likely to decrease in concentration.
Concentration of all pollutants reduced
except common soluble salts.


                                                    CRITICAL LEVELS
                          V            /


 Figure 3.  The effect  of  different  kinds of pollutants on the value

            of water  for irrigation.

                                     of Return Flow
The concentrating of some pollutants, such as salts, is an inescapable
consequence of consumptive use of irrigation water.  There are, however,
possibilities for regulating the concentration.  On the other hand,
the loading of a stream with pollutants can, in some instances, be
more nearly controlled.

Concentrating Salts

Even though it is not possible to prevent concentrating salts, it is
theorectically possible to regulate the concentration of the return
flow.  This is by some form of dilution of which there are several:
(a) regulating the amount of applied water that is returned to the
system (regulating the amount and time of leaching), (b) importing
water for direct dilution or alternative uses, (c) increase the water
supply by weather modification, and  (d) desalt some of the water and
use for dilution.

Such activities as increasing the supply by weather modification and
desalting introduces new problems.  More water by  increasing precipitation
will undoubtedly bring more salt and sediment  from the watershed.
This will depend on where and how the increase comes.  Brine disposal
is a problem created when water is desalted somewhere along a  river

Loading Effects

Considerable of the  salt  loading effects can be reduced by diverting
salty water  from the supply.  This may include diverting natural
salty water  as well  as seepage waters that have accumulated  salt.
Establishing a drainage network whereby most of the drainage water
is  from the  soil profile  offers some hope  for  reducing  loading.   In
such a system the  soil would be managed so  as  to  keep  the  salty groundwater
below  the  active drains and,  thereby, reduce  the  amount of  loading.
Lining of  canals,  ponds,  etc.,  to prevent  seepage and  leaching from
non-irrigated soil is  another  practical method.   Exclusion  of  lands
containing  appreciable amounts  of residual  salts  or pre-leaching  of
such soils  and diverting  the  drainage waters  also prevents  the addition
of salt to  the  system.  Drainage waters  from new  lands  usually contain
the greatest amounts of  salts  because  of  the  salt in  the  profile  not
previously exposed to  leaching water.

The loading of  pesticides,  plant  nutrients,  and  sediments  can largely
be controlled by  preventing the erosion  of the top soils  and runoff.
We recognize that  there will  be spillage  and accidental discharge as
well  as movement  of some  soluble  pollutants through the soil and  into
 the drainage waters.

The identification of kinds, amounts, and sources of pollutants and utilizing
the mentioned control methods may appear relatively simple.  This would not
be a proper evaluation of the situation.  The salinity problem alone is
highly variable and as expressed by the Bureau of Reclamation:

             Each irrigated area has a different effect on
             quality depending upon properties of the soils and
             substrata in the drainage area, number of years the
             land has been irrigated, number of times return flow
             is reused, nature of the aquifers, rainfall, amount of
             dilution caused by surface wastes, temperature, storage
             reservoirs, vegetation, and types of return flow

It is our opinion that loading of heavy metals and boron by industry
and domestic users offers major hazards to irrigation agriculture.  There
is no known method of detoxifying the soil once critical levels of heavy
metals have been reached.  Boron compounds have many uses; and hence,
there are many sources of contamination.  It is very harmful to plants at
low concentration--levels well below the tolerance levels to man and

Beneficial Effects

Not all of the effects on the quality of return flow are adverse.
The soil can improve the quality by: (a) filtering suspended solids,
(b) removal of heavy metals, pesticides, and phosphate by chelation,
sorption and/or precipitation, (c) degrading detergents, wastes and
other organics, and (d) by providing the death time for harmful micro-
organisms.  Such benefits can be used to counter the disadvantages
resulting from the consumption of water.  Eliminating irrigation within
a basin may reduce some of the salt loading and concentrating of the
salt,  but certainly would not eliminate the salt problems, and it  could
increase some of the problems created by other pollutants.


1.  Pillsbury, Arthur F., and Harry F. Blaney, "Salinity Problems
    and Management in River Systems," ASCE 92(IRI):77-90, March 1966.

2.  lorns, W. V., C.  H. Hembree, D. A. Phoenix, and G. L. Oakland,
    "Water Resources of the Upper Colorado River Basin Basic Data,"
    USGS Prof, paper 442, 1964.

3.  U.S. Dept. of the Interior, "Quality of Water,  Colorado River
    Basin," Progress report No. 3, January 1967.

4.  U.S. Dept. of the Interior, "Quality of Water,  Colorado River
    Basin," Progress report No. 4, January 1969.

5.  Federal Water Pollution Control Administration,  "The Cost of
    Clean Water," Vol. II, Detailed Analysis, USDI,  1968.

6.  Van Denburgh, A. S., and J. H. Feth, "Solute Erosion and Chloride
    Balance  in Selected River Basins of the Western Conterminous
    United States," Water Resources Research, Vol. 1:537-541, 1965.

7.  Doneen,  L. D., ed., "Proceedings,  Symposium on Agricultural
    Waste Waters," Report No.  10, Water Resources Center, University
    of California, Davis, April  1966.

8.  Doneen,  L. D., "Effect of  Soil Salinity and Nitrates  on Tile
    Drainage in  the  San  Joaquin  Valley of Calif.," Water  Science
    and Engineering  Papers 4002, Dept. Water Science  and  Engineering,
    University of California,  Davis,  December 1966.

9.  Grinstead, R. R.,  et al.,  "Feasibility of Removal of  Nitrates  from
    San Luis Drain Waters by  Ion Exchange," A report  to  the U.  S.
    Bureau of Reclamation, Dept. of  the  Interior, by  the  Dow Chemical
    Company,  August  26,  1968.

10.  Biggar,  J. W.,  and R. B.  Corey,  "Agricultural Drainage  and
    Eutrophication," International  Symposium  on Eutrophication,
    Madison, Wisconsin,  June  11-16,  1967.

11.  Johnston, William R.,  F.  I.  Ittihadieh,  and Arthur F.  Pillsbury,
     "Nitrogen and Phosphorus  in Tile Drainage Effluent," Soil  Science
     Society  of America Proceedings,  Vol.  29(3):287,  1965.

12.   The  Secretary of Agriculture,  and the Director  of the Office of
     Science  and  Technology,  "Control of Agriculture-Related Pollution,"
     A report to  the President, 102 pages, Washington, D. C.,  January  1969.

13.  Wadleigh, C. H., "Wastes in Relation to  Agriculture and Forestry,"
     USDAMisc.  Publ. No. 1065, Washington, D. C., March 1968-

 14.  Miner, J. R., R. I. Lipper, L. R. Fina, and J. W. Funk, "Cattle
     Feedlot Runoff--Its Nature and Variation," Jour.  WPCF, Vo. 38,
     No.  10, pp.  1582-1591, October 1966.

 15.  LeGrand, H. E., "Movement of Pesticides in the Soil," Pesticides
     and  Their Effects on Water Symposium  Special publication, Vol.
     8:71-77, American Society of Agronomy, Madison, Wisconsin, 1966.

 16.  Nicholson, H. Page, "Pesticide Pollution Control," Science,
     Vol. 158:871-876, 1967.

 17.  Johnston, William R., F. T. Ittihadieh, Kenneth R. Craig, and
     Arthur F. Pillsbury, "Insecticides in Tile Drainage Effluent,"
     Water Resources Research, Vol. 3(2):525-537, 1967.

 18.  Nash, Ralph G., and Edwin A.  Woolson, "Persistence of Chlorinated
     Hydrocarbon Insecticides in Soil," Science, Vol. 157:924-927,
     August 25, 1967.

 19.  Texas A&M University, "Water for Texas," Water Quality and Chemicals
     Conference, Proceedings 9th Annual Conference Water Resources
     Institute, November 1964.

 20.  Weibel, W. R., R. B. Weidner, J.  M. Cohen, and A.  G.  Christiansen,
     "Pesticides and Other Contaminants in Rainfall and Runoff," Jour.
     AWWA, Vol. 58(8):1075-1084, August 1966.

 21.  Faulkner, Lindsey R., and W.  J.  Bolander,  "Occurrence of Large
     Nematode Populations in Irrigation Canals  of South Central Washington,"
     Jour-  International Nematological Research,  Vol.  12:591-600,
     (A-011-WASH), 1966.

22.  Meron,  Aharon, and Harvey F.  Ludwig,  "Salt Balances in Groundwater,"
     Jour.  Sanitary Engineering Div., ASCE, pp. 41-61,  June 1963.

23.  Water Pollution Control Board, "Studies of Waste Water Reclamation
     and Utilization,"  State of California, Publ. No.  9,  1954.

24.  McGauhey, P.  H., "Engineering Management  of Water  Quality,"
     McGraw-Hill Book Co., New York,  1968.

25.  Federal Water Pollution Control  Administration,  "Water Quality
     Criteria," Report of the National Technical Advisory  Committee
     to the  Secretary of the Interior, 215 pages,  Washington,  D. C.,
     April 1968.

26.  Department of Water Resources, "San Joaquin Valley Drainage
     Investigations," State of California,  Sacramento,  Bulletin 127,
     January 1965.

27.  Berry,  William L.,  and Edward D.  Stetson,  "Drainage Problems
     of San  Joaquin Valley," Jour.  Irrigation  and Drainage Div., ASCE,
     Vol.  85 (IRI):97-106,  September 1959.




                             Stanley J.  Dea I/
Although the Federal role in water pollution has evolved over a 65'
year period, there has not been a very long history of interest or
concern with the subject of wastewater reclamation.  In fact, many of
the primary and secondary sewage treatment processes in use today were
known some fifty years ago, and it was not until the early 1960's
that the degradation of our waters as a resource became a national issue.

This awareness, occasioned through the accumulated and continuing
effects of rapid economic and population growth, culminated in the
passage of two very important and far-reaching laws -- (1) the Water
Quality Act of 1965 which required that standards of water quality be
established, implemented and enforced for all interstate and coastal
waters of the United States, and  (2) the Clean Water Restoration Act
which provided for the Federal Government's participation in financing
needed treatment plants and in undertaking, fostering and sponsoring
needed research, development and demonstration efforts.

Under these laws, the 50 states have proceeded to establish standards
of water quality for each  of their interstate waters, and many States
have  further chosen to establish  such standards  for their intrastate
waters as well.  The standards are not uniform across the country, but
vary  as you might expect according to individual circumstances relating
to  climatic zone, hydrogeologic  factors, present water quality,  and
a host of other  location-related  variables.  There are only  two  uniform
guiding principles:  (1)  the  standards for  any given river, or  stretch
of  river, must  spell out the beneficial uses which  the public  expects
to  make of  the water resource  (i.e.  recreation,  fishing, municipal or
industrial  water  supply, etc.) and  (2)  the  criteria chosen to  support
such  uses   (i.e. dissolved oxygen content,  temperature,  pH,  etc.) must
be  adequate  to  protect  and in  fact enable  such  uses to be made.

The establishment  of  river uses  and  criteria has profoundly  affected
 the philosphy  of water  quality management  on  a  national  scale.   This
has been  particularly  true in  the case  of  wastewater  treatment for
pollution control.   In the United States,  to  date,  treatment requirements
have been usually  expressed as removal  efficiencies.   The  removal
 efficiencies in turn have been almost directly  related to specific
 treatment operations  or processes.   However,  the stated  purpose of  the
Water Quality  Act of 1965 is to "enhance the  quality  and value of our
 water resources."  Treatment requirements become more meaningful when
       —  Formerly Chief, Agricultural Pollution Control Section;
 Office of Research and Development, Federal Water Pollution Control
 Administration, U. S. Department of the Interior, Washington, D. C.


They are  expressed  in  terms of quantities of  impurity when  the  objective
is attempting  to protect water quality.  Therefore, requirements are
moving  to the  concept  of specifying  the  total quantity of impurity which
may be  discharged into receiving water.  The means of accomplishing
that quantity  are being determined by  the industry or the municipality,
because in most cases, it is  this quantity which  impairs  the  quality
of the  stream.

It is now recognized that specification  of the quantity of  impurities
is the  only means to maintain the quality of the  receiving  water where
there might be an increase in wastewater flow.  Thus, as population
grew or industrial  activity increased, more effective treatment or
control devices would  have to be installed in order to meet the established
quantity  requirement.

Brief reflection upon  the dual problems  of water  supply (quantity)
and water pollution (quality) should manifest the inseparable bond
which exists between them.  If water were used only once and  then
disposed  of, any degree of water quality degradation would  be incon-
sequential.  But, except in rare cases,  reuse does occur in some form.
Gone are  the days when man can readily depend upon the hydrologic cycle,
upon dilution, or upon natural purification to restore the  quality and
quantity  of his water  source.  Thus, when one user degrades the water
quality so as  to deny  reuse to the next  user, the latter's water supply
is diminished by that  amount.

By restoring the quality of waste effluents to higher and higher degrees,
the point is reached when they can be deliberately and directly, or
indirectly, reused  for any beneficial purpose, even for potable water.
In addition to alleviating pollution, the renovation of wastewater can
simultaneously augment the water supply.  Thus the concept  of complete
water renovation solves the problems of water pollution and water supply,

Presently, heavy reliance is  placed on secondary treatment  of municipal
wastes and its equivalent for industrial waste to achieve and maintain,
in a reasonably short  time frame, the quality of water as it is specified
in the standards for the receiving water.  The standards for each State
include a so-called "Implementation Plan," which is usually a listing
of specific needs to install  new secondary sewage treatment plants or
upgrade and improve existing  primary plants for given locations and
in a given time frame.   At some locations, however, plans of the States
call for primary treatment only; at others,  even secondary treatment
will not suffice to restore quality, or to maintain it in the face
of expected future economic and population growth, and the plans call
for the installation of tertiary, or "advanced waste treatment."

From the overall view of potential water supply shortages in the
United States, advanced waste treatment has the greatest promise at
locations where the municipal wastewater is presently discharged into

the ocean or other sink and is thus lost for reuse.  These locations
include some of the largest American cities, such as New York, Los
Angeles and San Francisco, where population concentrations are high,
and where it is becoming increasingly costly to follow the conventional
approach of reaching out into more remote interior locations to import
additional water supplies.  This also includes the arid and semi-arid
regions where treated effluents have not been reused.

One of the largest alternative sources of water available to a city is
the wastewater which it has thus far thrown away.  As a rule of thumb,
some 60% to 90% of the water delivered to a city is returned to waste
discharge.  If treated to the conventional secondary level, this
water contains usually less than 0.1% of impurities, and advanced
waste treatment can further serve  to make it completely suitable for
a wide range of reuses.

The United States  learned a lesson in this regard during the severe
drought of 1965 in the Northeastern Region.  New York City was particularly
hard hit; air conditioning was shut off; businesses shut down or lost
customers; restaurants could  serve a glass of water only upon request.
Yet 3 billion gallons of unused water were flowing down the Hudson
River  into the ocean each day -- about three times the amount consumed
daily by  the City.  The water was  unusable because it was polluted.

Emergency conservation measures were instituted  immediately  to relieve
the most  pressing  hardships.  Studies were  started to consider the
alternatives available  to  secure additional  fresh water supplies  to
prevent  a recurrence of water shortages  in  the  future.  Sea water
desalting and waste water  purification were  the  two most  important
alternatives to  importation from  the interior watershed.

Not  surprisingly,  desalting came  out second  best to  advanced  waste
 treatment.   A  feasibility analysis of a  100 million  gallons  per  day
 advanced waste  treatment  plant which could  be  added  to  an existing
 secondary sewage  treatment plant  showed  that the plant  could be
 constructed for $33 million (at  then-prevailing prices  and interest
 rates)  and  would  produce  and deliver potable water into the  City's
 system at about  16 cents  per 1,000 gallons.   The costs  for the desalting
 alternative  were  considerably higher.   It is likely that  this desalting
 cost disadvantage will continue in most locations, if only for the
 simple reason that sea water contains  some 3.57, of dissolved salts
 plus some organic matter -- equivalent  to more tihan 35 times as much
 foreign matter as secondary sewage effluent.

 The advanced waste treatment facility postulated for the New York City
 situation envisioned the following steps:

 A.  A second stage, intensive biological treatment process would be
     installed following the existing high rate activated sludge treatment.
     This second stage bio-oxidation would provide more than 90%

      removal of all biochemically oxygen-demanding (BOD) organic
      compounds entering the treatment plant.   In addition,  the 3.5-hour
      additional aeration would eliminate essentially all of the ammonia
      and organic nitrogen from the waste stream.

 B.    The effluent from the biological treatment process  would  be
      subjected to a coagulation-sedimentation and sand filtration
      sequence similar  to that  utilized in conventional water treatment
      plants.   These purification procedures are capable  of  removing
      both suspended and colloidal particles to produce a sparkling
      clear water.   The alum coagulation also  serves  to reduce  bacterial
      and viral disease-producing organisms.

 C.    From the filters, the water would pass through  deep beds  of
      granular activated carbon which will adsorb residual dissolved
      organic  impurities from the water.

 D.    While this series of purification steps  will yield  a high quality
      water,  a final positive disinfection step,  complete with  fail-safe
      provisions and a  very large factor of safety, would be  imposed.
      The disinfection  step would employ three separate chlorination
      contactors;  while one is  being filled and another emptied,  the
      third will provide an absolutely certain contact  with  free  chlorine
      This batch or  fill-and-draw system would eliminate  even a remote
      possibility of inadequate contact time for  bacterial and  viral

 E.    Quality  of the product water would  be continuously  monitored
      and,  in  fact,  the entire  plant would be  highly  instrumented both
      for control  and for quality monitoring purposes to  assure  the
      complete  safety and reliability of  the operation.

 F.    The product  water would be  pumped through a 1000-ft. force main
      to  an existing but presently unused  shaft,  extending downward
      directly  to  the city's principal  water distribution tunnel  to
      Brooklyn  and Queens,  and  injected into the  tunnel at a  pressure
      of  150 psi.  The  tunnel now carries  400  to  600 million  gallons
      of  tap water each day which would provide a  dilution factor of
      at  least  3:1 for  the  renovated  water.  The  combined  supply would
      be  completely  potable  in  every  respect and  should meet  or exceed
      the highest  Public  Health Service Drinking Water  Standards.

 The treatment  process  proposed for  New York City  is only one of many
 alternative systems available.   The  final  system  selected depends on
 the use  of the water and  the impurity  to  be removed.

 In returning to the broader  effort  in  the  United  States  to research,
develop, and demonstrate new technology for sewage treatment,  this
discussion will attempt  to  categorize  the  effort  in general  terms
 first, and then proceed  to  the specifics.  Basically, our most urgent
needs fall into two broad categories:

(1) We need treatment processes for more effective removal of organics,
nutrients, and suspended solids, which are now only partially removed
by "conventional" treatment; and

(2) We need processes for the removal of dissolved pollutants not
ordinarily removed at all by "conventional" treatment.  Within and
across these two broad categories, two lines of attack are being

   (1) Modifications of "Conventional" Processes; and
   (2) "Advanced" or Tertiary Processes

Now to the specific efforts underway:


    In this category some eight projects are now in the design or
    construction stages, and three projects are already in operation.

    A.  Modification of the Activated Sludge Process  for Increased
        Nutrient Removal

        At Manassas, Virginia, and at three locations in California
         (Santee, Irvine, and Chino), these study efforts are underway:

         1.  Nutrient removal through biological oxidation; involving
            very high organic  loadings in the aerators and rapid
            solids-liquid separation.

         2.  Progressive bio-oxidation; aerobic  oxidation of nitrogen
            compounds to nitrates, followed by  anaerobic conversion
            of  nitrates to  nitrogen  gas.

         3.  Three-stage nitrification-denitrification; high-rate
            activated sludge process, treatment with  sludge enriched
            with nitrifying bacteria, denitrification with anaerobic

     B.   Combined Trickling  Filter -  Activated  Sludge  Process

         At Dallas,  Texas,  and  Ventura,  California,  projects are  underway
         to evaluate tandem use of both  processes  in different  sequences
         to determine how  trickling filters must be  supplemented  by
         additional  treatment  to produce  satisfactory  effluent.

     C.   Dual-Train Experimental Activated Sludge  Plant

         At Washington,  D.  C.;  one train to  furnish effluent  to tertiary
         processes,  the  second  to study  modified activated sludge
         processes.   (Operates  in conjunction with existing tertiary
         pilot plant.)

     D.  Polymer Addition to Activated Sludge Process for Phosphorus

         At Washington, D. C.; an operational project involving addition
         of three polymeric materials to raw sewage to increase sedimentation
         of solids in primary settling tanks.  Evaluation of effects
         of this treatment throughout plant, including the anaerobic

     E.  Mineral Addition to Activated Sludge Process for Phosphorus

         At Pomona,  Santee and Irvine, California; lime precipitation and
         ammonia stripping for treatment of digester supernatant;  addition
         of sodium aluminate to aerator;  single-stage tertiary clarification
         and filtration using lime or alum as coagulant;  Dorr-Oliver
         process involving chemical and biological methods for phosphate
         removal from raw wastewater, with lime recovery  and reuse.


     Some ten tertiary treatment  research and demonstration projects
     are operational  in various parts of the United States, and another
     nine are in the  design or construction stage.  The areas under
     investigation include the following:

     A.   Chemical  Coagulation,  Sedimentation, Filtration,  and Granular
         Carbon Adsorption - Emphasis on  tertiary processes to reduce
         suspended nutrients and  organics because they contribute  so
         heavily to  the overall water pollution problem.

     B.   Direct Carbon Treatment  of Secondary Effluent -  For removal of
         organics  from clarified  secondary effluents.

     C.   Ammonia Stripping - Countercurrent air contacting lime-clarified
         secondary effluents containing nitrogen as ammonia as organic

     D.   Electrodialysis - Lime coagulation and granular  adsorption
         precedes  effluent passage through electrodialysis stack;  40%
         of dissolved salts  removed with  a wastestream only 10% of

     E.   Ion Exchange - Parallel  operation of electrodialysis  unit for
         comparison of process  economics.

     F.   Reverse Osmosis -  Different membrane configurations  tested  on
         same wastewater to  achieve  higher  flux  rates  and  product-to-
         waste  ratios,  with  critical determination of  pretreatment
         techniques necessary  to  prevent  fouling and deterioration of

              Summary of Research Progress Achieved to Date

A wide range of wastewater treatment processes have been evaluated from
laboratory-scale through pilot-scale in recent years.  The treatment
methods investigated include processes for suspended solids, organic
and inorganic removal, nutrient removal, and, conjuctively, certain
aspects of the biological processes.  A number of processes have been
studied extensively enough to assess their feasibility with a fair
amount of accuracy.

For wastewaters with appropriate mineral composition, lime clarification
will effectively remove suspended solids and the nutrient phosphate.
Alum clarification is expected to be successful at a cost of 8 cents/1,000
gallons at the 10-mgd plant.  For organics removal, activated-carbon
treatment is promising.  Granular carbon treatment without clarification
of the feed can be carried out for about 8 cents/1,000 gallons or
less at the 10-mgd level on high quality secondary effluent.  Powdered
carbon treatment has been estimated to cost about  12 cents/1,000 gallons
at the same plant capacity, provided the carbon can be reactivated;
this treatment yields a highly clarified water.  For removal of gross
inorganic content, electrodialysis treatment should be possible for
about 16 cents/1,000  gallons or  less in a 10-mgd plant, although pre-
treatment appears to  be a necessity.  Ion exchange will cost about
25 cents under the same conditions.  Reverse o smosis has  great promise
for effective results.  It  is still in a developmental stage and costs
are difficult to estimate.  Removal of nitrogen, either as  ammonia  or
nitrate, is a difficult problem.  An air-stripping process  for ammonia
may be technically feasible at 3 cents/1,000 gallons or less for a  10-mgd
plant, but requires  lime clarification  to adjust pH  to 11 or above.
Studies of denitrification  of a  highly nitrified effluent on granular
stone or sand shows  promise for  nitrate removal at 3 cents/1,000 gallons
for a  10-mgd plant.   Electrochemical treatment appears at present  to
be economically unfavorable.

                              The Outlook

In  summary,  a great  deal  of research progress has  been made, and  the
outlook  for  the  future  is bright.   A range  of processes have been
evaluated  and  improved  to  the  point where  the designers of new  systems
have  a great range  of technological options  in  selecting  efficient
 treatment  processes  for various  wastewater  streams and  effluent
qualities.  We  must  depend  on  current  and  future  studies, however,  to
provide  the  optimum process selection.

As  in the  past,  the  economics  of particular processes  and combinations
will  greatly  influence  the  design and  selection of individual  systems.
 The  costs  set  forth in the  table below apply to a 10-mgd  plant  and
 include  amortized  construction,  operation and maintenance costs;  they
 are  projected  best estimates  for the tertiary processes  shown,  and
 are based  on actual experience for the conventional primary and
 secondary  treatment stages.

                     Process                              Cost
                                                  (cents/1,000 gallons)

     Primary treatment                                      7.5
     Activated sludge                                      11
     Microscreening                                         1-5
     Coarse Media                                           2.5
     Fine Media                                             3.5
  Phosphate Removal
     Mineral Addition to Aerator                            3
     Coagulation, Sedimentation  (lime ovalum)               7
     Coagulation, Sedimentation, Filtration                10
  Ammonia Stripping                                         3
  Granular Carbon Adsorption                                4-8
  Dissolved Inorganic Removal
     Electrodialysis                                       14
     Reverse Osmosis                                       25
     Ion Exchange                                          25

In summary, advanced treatment for the removal of nutrients, organics,
and  inorganics can be accomplished for about 26-30 cents/1,000 gallons
compared to 11 cents/1,000 gallons for secondary treatment.  However,
the wastewater reclaimed by the improved or advanced treatment has
economic utility and value as related to the reuse application selected
for it, and, by logical extension, becomes once again available for
sale, to the user.

As a final word  about economies of scale for the electrodialysis and
reverse osmosis dissolved inorganic removal processes, pre-publication
results of current work by Interior's Office of Saline Water indicates
that a 30-mgd plant located in a Southern California could demineralize
secondary effluent at 21 cents/1,000 gallons for the electrodialysis
process, and at 22 cents for the reverse osmosis process, both at 1968
prices .

                          FROM IRRIGATED AREAS
                        A DEMONSTRATION PROJECT


                          Norman A.  Evans I/
The Upper Colorado River Basin comprises approximately 220,000 square
miles in the states of Utah, Colorado, New Mexico, Arizona and Wyoming.
The main stem of the Colorado River heads in Colorado at the Continental
Divide and runs more than 500 miles southwestward through Utah and
Arizona to a place called Lees Ferry, which marks the division between
the Upper Colorado River Basin and the Lower Colorado River Basin.  This
river and its tributaries literally is the lifeline of southwestern
United States.

Although problems abound in the utilization of the water, none is
considered so great as the mineral degradation which occurs as the
water flows westward.  This problem is serious because the basin is
approaching conditions of full development and utilization of the
available water supply.

The seriousness of mineral pollution in the Colorado River is illustrated
by the 1963 salinity crisis at the U. S.-Mexico border arising from
saline drainage from the Welton-Mohawk irrigation project.  Here,
as a  solution, the federal government provided a waste canal  to carry
the return flow from the project around Imperial Dam.  Such drastic
measures cannot be expected to be used to solve other salinity problems
along the river.  Methods and practices must be developed which will
afford control of the  salt load in the river while permitting continued
use of the water.

Salts in the  river accumulate from several sources but the heaviest
contributor is water returning to the river from underground  drainage
after it has  been used for  irrigation on  lands near  the  river.

Figure 1 represents  a  typical geologic  cross  section along  the upper
Colorado River.  Note  the shale base material over which has  been
deposited  alluvial material which now constitutes  the irrigated  soil.
This  figure also shows a water budget,  indicating water  applied  as
irrigation on the  land,  seepage  losses  from the canal, deep  percolation
into  the ground water  of a  fraction  of  the irrigation water  applied,
and evapotranspiration into  the  atmosphere of a part of  the  irrigation
water applied.   Lastly,  a component  of  the  irrigation water applied
 is  shown running back  to the  river  as  surface runoff.
       I/  Director,  Natural Resources Center,  Colorado State University,
 Fort Collins.


Water returned to the atmosphere by evapotranspiration leaves behind
in the soil any salt which it contained when it was applied to the land.
That salt residue left behind may be dissolved by deep percolation
water and carried back to the river.  This is one source of salt load
returning to a river and in some cases, especially where the irrigation
water contains a heavy load of salt, can contribute a large salt load.
Seepage from a canal passing through the soil as it moves toward the
river may also dissolve salts from crystalline form in the soil and
thereby gain a load of salt.  These two processes by which salt is
added to return flow might be called (1) evapotranspiration residue,
and  (2) solution pickup.

In the Upper Colorado River the  irrigation water has relatively low
salt load,  on the order of 300 ppm, so the evapotranspiration residue
is relatively small.  On the other hand, solution pickup is relatively
high because the parent material and base material contains large
amounts of  crystalline salt.  Figure 2 shows electrical conductivity
 (ECX1CH) and exchangeable sodium percentage  (ESP) in soils and shale
of Grand Valley.

Figure 3 is the Upper Colorado River Basin showing the main stem and
principal  tributaries.  The numbers show the annual salt load at three
points expressed  in  tons.  At Cameo, Colorado, the annual  salt load
 is  1,549 tons.  At Cisco, Utah,  the annual salt  load is 4,242 tons.
The  Gunnison River at Grand Junction adds  1,519  tons.  Quick  arithmetic
 shows  that the  salt  load gain in this  section of the main  stem of  the
Colorado River  is 1,174 tons.  This  is  almost equal to  the  load at
Cameo  and  is primarily the result of solution pickup in return flow
 from irrigated  land  along the river.

 The  purpose of  this  paper is  to  summarize  a  demonstration  project  which
 has  been  initiated  in  the Grand  Valley area  (Figure 3)  for the purpose
 of showing that saline agricultural return flows are controllable  and
 that if  improvements in water management  practices  are applied,  the
 salt load  returning  to  the  river will  be  reduced.

                       Mechanics of Return Flow

 Before describing the  demonstration project, a brief discussion of the
 nature of  return flow will  be helpful.  Figure 4 represents a typical
 irrigated  area along the  river.   Phreatophytes are illustrated because
 the water-loving plants  are almost invariably found along western rivers
 Now let us look at the hydrograph of return flow as computed from a
 2-dimensional mathematical  model.   Figure 5 shows the  return flow
 during and after the irrigation season.  Note that the return flow
 is negative at first.   The  water table at time zero is assumed hori-
 zontal and the negative  return flow represents phreatophyte withdrawal
 of water from the river.   However, as the groundwater rises, flow
 returns to the river reaching a peak shortly after the irrigation
 season ends and gradually declining thereafter.  Let's look now at the

 o  15
                             EC x I01
                 0-9             9-18           18-30
                                        DEPTH  IM INCHES


                                                                   VALLEY BOUNDARY
                          IRRIGATED  LAND

                               CANAL SEEPAGE, PHREATOPHYTES
                               ALONG RIVER, OVER-IRRIGATION
               REDUCED 50%, OVER IRRIGATION
                 REDUCED 50%
                      DAYS AFTER IRRIGATION

 effect  of improved  water  management  by eliminating canal seepage,
 reducing the  area of phreatophytes by 50 percent,  and reducing the
 amount  of deep  percolation  by  50 percent.   By  eliminating canal
 seepage,  we notice  first  that  the peak runoff  is  smaller and  occurs
 earlier.   Comparing the areas  under  the two curves indicates  a reduced
 total volume  of return  flow.   It has been frequently  observed that
 salt  load in  return flow  is proportional to volume of water returned,
 so  we might expect  a reduced total amount  of salt  to  enter the river.

 The mathematical  model has  been  used also  to illustrate  the effect
 of  system geometry  on return flow.   Figure 6 shows a  river valley with
 the main canal  located one-fourth the distance from the  river to the
 valley  boundary.  Canal seepage  is considered  for  a given period of
 time  and  the  resulting hydrograph of return flow  is displayed.  Note
 that  it  has a high  peak rate of  return dropping off rapidly.   The second
 case  locates  the  canal at the  valley boundary.  This  is  generally more
 typical  of the  Colorado River  Valley.  The same amount of seepage
 during  the same time is reduced  and  the return flow hydrograph is seen
 to  be much flatter  and with the  peak occurring  much later.  Of course
 both  situations return the  same  volume of  water to the river  but with
 a different rate  distribution.   Unfortunately,  we  know very little
 about the effect  of return  flow  rate on solution pickup.

                          Demonstration Project

 A demonstration project to  show  effects of seepage  reduction  on salt
 load was  proposed by the  principal water-using identities  in  the Grand
 Valley  near Grand Junction, Colorado.   Six irrigation  companies, a
 power company,  and  a drainage  district combined resources  to  form a
 corporation for the  purpose of conducting  the  demonstration and study.
 They received a grant from  the Federal Water Pollution Control Admin-
 istration for construction  and project evaluation.  A  contract was in
 turn negotiated by  the corporation with Colorado State University for
 assistance in evaluating  the results  of the project.   The  study area
 is  represented  in Figure  7.

 The first  step  in the evaluation  program was a  "before treatment"
 inventory  of water  and salt budget in the  demonstration  area.  Canal
 seepage  losses  have  been  measured and  a plan for lining  certain sections
 of  canals  is being  formulated.  This  lining will be constructed during
 the forthcoming winter season prior  to  the  1970 irrigation season.
An  "after  treatment"  inventory will  be  made during  and after  the 1970

                              Water Budget

Water flow measurement in all canals, ditches,   and  drains  leading
 into and  out of the   study area are being made using a wide variety of
measuring methods.  Measuring flumes have been  used in some places,
existing  structures  have been calibrated for measurement in others,
and dye-dilution has been used for measurement  where other methods






                                                    IRRIGATED  AREA


      i    ..Government     //
      f~" *~~-.,------^
	 — *•
\ \
\ \

were not possible.  Evapotranspiration estimates will be made from a
survey of vegetation type and density.  The estimate will be made
by the Jensen-Haise method of calculation.

Groundwater flow will be calculated from hydraulic gradient and per-
meability data.  A grid of piezemeter installations has been made
with which the groundwater flow net can be measured.  Permeability
measurements in situ by standard methods will also be made.  River
flow measurements upstream and downstream from the demonstration area
also will be made.

                              Salt Budget

Salt monitoring the river will afford the final evidence of positive
benefit  from reduction in canal seepage.  However, the  lag time in
return flow for this particular system  is uncertain so  salt monitoring
in  the groundwater will also be performed.  A grid network of porous
cups has been  installed in the alluvium at several depths from which
groundwater samples will be extracted.  Changes in sale flux at these
sampling points will add evidence  as  to the effect of reduced volume
of  groundwater flow.


Water users in the Grand Valley area  of Colorado  have  long recognized
the damaging effects of canal  seepage and excess  water  application  in
irrigation.  They have seen  it  in  the progressive deterioration of
agricultural land beginning  shortly after irrigation was introduced
to  the area.   They also recognized river  quality  deterioration which
has been outlined in these remarks.  With the  cooperation  and  assistance
of  the Colorado Water  Conservation Board  and  the  strong interest  of
the Federal Water Pollution  Control Administration,  these  citizens
set about  doing  something  about  it through  a  demonstration  project
 financed by FWPCA.   Canal  seepage  will  be reduced.   This should  reduce
by  1/2  the volume of return  flow,  and affect  a significant  reduction
 in  salt  load originating  from solution  pickup.  We  believe  also  the
 attention  focused upon water management through this  demonstration
will result  also  in  greater  effort toward better  irrigation water
management on  farms  which  in turn  will  further reduce  return flow

While return flow control  will reduce salt  load,  a certain amount is
 essential  for  maintenance  of salt  balance and we  do not suggest  that
 elimination of all return flow is  an objective -  rather its control
 to  satisfy salt balance  requirements.

 It  is expected that  the  experience gained in this project will serve
 as  a guide to other similar areas  along the entire Colorado River as
 well as  other  areas  of the western United States.



              Richard C. Bain, Jr. and John T. Marlar !/


All rivers do not flow to the oceanic sea; some create their own
unique inland seas in the desert.  Desert lakes like desert lands
are harsh, and few life forms survive.  The tenuous balance between
vegetative cover and precipitation, animal life and water supplies
in arid lands is reenacted with different players in the desert lake.
Here survivors from a wetter past or newcomers introduced by man,
struggle in the specialized environment created by rivers without

The arid lands of the western United States contain numerous closed
river basins, or inland sinks, which have unique water quality and
ecological problems.  Each of these basins will support an inland
sea which typically is  increasing in salinity, has fluctuating water
levels and various ecological problems associated with salt, nutrients
or pesticides often from agricultural drainage.  Since these sumps
are rarely or never flushed,  the  trend is toward ecological imbalance
as a result of salt buildup.

Figure 1 is a comparison of recent  salinities  in six well-known inland
sinks in the Western United   States.  These inland seas are in various
Stages of "aging" as far as water quality is  concerned.  Several of
these seas are becoming more  saline at a rate  faster than nature alone
would dictate, because  the freshwater inputs  have been reduced or made
more saline by man.  Pyramid  Lake in western  Nevada is a good case
study illustrating the  effect of  inflow reductions on the aging process,
The Salton Sea,  in southern California receives relatively saline
inflows comprised of drainage from  irrigated  lands.  The water quality
and quality related problems  affecting aquatic life resources of
these rather different  desert lakes will be described to emphasize
the unique water quality management problems  which occur in inland
s inks.

                              PYRAMID  LAKE


Pyramid Lake  is  the  largest  remaining remanant of  ancient Lake
Lahontan.   Its  present  area  of  100,000 acres  is  only  one-fiftieth
that  of its  Pleistocene ancestor.  Pyramid  Lake  has been appropriately
       I/   Respectively,  Chief,  Operations Branch and Sanitary Engineer,
 Planning  Branch,  California/Nevada Basins, Federal Water Pollution
 Control Administration,  USDI,  620 Central Avenue, Alameda, California.








called North America's most beautiful desert lake.  Set at an altitude
of 3,800 feet in the practically barren Nevada desert, it is indeed
a rewarding sight to view its vast expanse of blue-green waters
ringed by peaks of brown.  It is a welcome relief from the surrounding
arid lands.

The life blood of any lake is its water source.  The Truckee River
which originates in Lake Tahoe and flows past Reno, Nevada, has been
the major source of water to Pyramid Lake (Figure 2).  The River
apparently supplied sufficient water to the Lake to result in a
reasonably constant surface elevation in Pyramid Lake until 1910 when
Xruckee River water was diverted at Derby Dam, the first reclamation
project undertaken in the West by the U. S. Reclamation Service, now
the U. S. Bureau of Reclamation.  Truckee River water is diverted
to the Carson River Basin where it is stored in Lake Lahontan for use
by the Truckee-Carson Irrigation District.  Drainage from the District
flows to the Stillwater Wildlife Refuge in the Carson Sink.  Although
there are some additional diversions from the Truckee River upstream,
the diversion at Derby Dam has been the most important single factor
affecting Pyramid Lake in this century.

Prior to 1910 the entire flow of the Truckee River was tributary to
Pyramid and Winnemucca Lakes.  Based upon data and analyses assembled
by Harding  (1) the total flow reaching  the two lakes during the period
1780-1905 averaged 546,000 AF/Yr.  After major diversions  for irrigation
purposes began in this century, Lake Winnemucca received no overflows
from Pyramid Lake and  finally evaporated to dryness  in 1939.  Recent
discharge of the  lower Truckee River tributary to Pyramid  Lake  (1957-67)
has averaged only 223,000 AF/Yr.  (2).

When  the diversion of  Truckee River water  through  the  Truckee Diversion
Canal  started, Pyramid Lake  held over  35 million  acre-feet  and had
a surface  area estimated at  over  120,000 acres.   Since that time, due
to  the  unbalanced water  budget,  the Lake has  increased in  salinity
by  about 50 percent,  receded some  80  feet  in  depth,  lost  15 million
acre-feet  in volume,  and 20,000  surface acres.  Figure 3  shows  salinity
trends  based on  several  data sources  (1,3,4).  During  the  1940"s
the famous  Lahontan  Cutthroat  trout  disappeared  from the  Lake.   It
was erroneously  concluded  by biologists at  that  time,  that the  increase
in dissolved solids  had  become  toxic  to the  trout.   However,  in  1948,
experiments demonstrated that  trout  could  survive lengthy exposure
 to Pyramid Lake  water.  The  lowering of the  Lake  surface  had  caused
 an increase in the  gradient  of  the lower Truckee  River and a  shallow
delta formed at  the  River's  entry  to the  Lake which  blocked the  access
of the trout to  their spawning  areas in the  River.   Thus  streambed
 changes caused by the lowering  of the  Lake had caused the population
 of cutthroat trout  to disappear.   Restocking programs have since
been  initiated by the Nevada Fish and Game Commission.

Although the ultimate tolerance of Lahontan Cutthroat trout to dissolved
 solids has not been adequately  defined, it is known that certain

                                                  <'LAKE ,'
                                                             V-PYRAMID LAKE
                                                                SAMPLING STATIONS
                                                                                     \   CARSON    ,
                                                                                     \  SINK  + '--'
Pyramid LOIM Indian R«s«rvo1ion
                                       DIVERS/OKI DAM

                                                                                     CARSON LAKE
                                                                      — IRRIGATION AREA
                                       FIGURE  2-  TRUCKEE -CARSON  RIVER AREA

               Derby Diversion Dam Completed
4000      5OOO

     TDS  (mg/l )
6000       7000

                SOLIDS -- PYRAMID  LAKE

 physiological changes may occur with continued exposure to IDS levels
 above 10,000 mg/1.  Trout transplanted to Eight Mile Lake, Wyoming,
 exhibited evidence of liver anomalies after two or three years in
 12,000 to 13,000 mg/1 TDS lake waters (5).  Even though the fish were
 said to be of "good sporting quality" no assurance was given that the
 trout population could be maintained indefinitely at IDS concentration
 of 13,000 mg/1.  These experiences should serve as advance warnings
 of the probable future effects of the imbalanced water budget of
 Pyramid Lake.

 Other fishes of interest include the Cui-ui sucker (Chasmistes cujus)
 which is believed to occur only in Pyramid Lake.  This species has
 adapted to the changed hydrologic regime and presently spawns in the
 gravels around the shore of the Lake.  The Cui-ui is included on the
 Bureau of Sport Fisheries and Wildlife list of endangered species.

 The apparent effects on the biota and desired use of the Lake have
 thus far been intimately connected with the physical changes caused
 by man rather than from the chemical or biological changes resulting
 from his actions.   The effect of physical changes which prohibited
 the spawning run of the Lahontan Trout is not the only problem caused
 by lowered lake levels.   A $500,000 park being planned for Pyramid
 Lake has also been affected because boat launching facilities and
 restroom facilities will eventually have to be moved once  the Lake
 level has receded  from them.

 Pyramid Lake Water Quality

 Chemical  and biological  changes may be more  subtle.   A brief  water
 quality survey by  FWPCA in the  fall of  1968  was  performed  in  order to
 document  the present  state of water quality  in Pyramid Lake  and provide
 base  data from which  to  estimate probable future  conditions.   These
 are the  only known detailed  data on the  hypolimnion  of the Lake.
 Although  the sampling  was performed after the  fall overturn had started,
 it  is apparent that a  stable  stratified  condition  still existed.
 The bottom of the  epilimnion  was noted at about  70 feet, while the
 summer  depth has been  recorded  at 20  to  25  feet  (3).

 Dissolved  oxygen,  temperature,  and  salinity  profiles  for two  stations
 within  the Lake are shown in  Figure 4.  These  profiles  demonstrate
 the effect of thermal  stratification within  the  lake;  organic matter
 which falls  from the epilimnion decomposes in  the deeper waters and
 produces  the  characteristic oxygen  depression  found  in  many lakes.
 The stratification  of  dissolved  solids as indicated by  the conductivity
 measurements  is indicative of the large evaporative  loss experienced
 by  the Lake during  the stratified period  and the lack of exchange
 between the upper and  lower portions of the Lake during stratification.
 The mean TDS was 5420 mg/1 consisting principally of  sodium, chloride
 and bicarbonates.   TDS levels were below  3500 mg/1 in  1882 and below
4000 in 1933.

              DO(mg/l )

            5         10

             (TEMP  C°)
            10     ^    15
i r
Conductivity ^^j
.s"^ x/



J^~ Temp
X ' I v
/ / /
                  DO Probe

                 STATION No. 3
                Off Sutcliffe
                 Oct. 1968
                     15 0
                    2O 5
   DO (mg/l)

 5          10

 (TEMP C°  )
10      _  15
                                    STATION No. 4
                                   Off Truckee  River
                                     Oct. 1968
8700      8900      9100 85OO    8700

                                 8 OXYGEN

                               PYRAMID  LAKE

 The concentration of the nutrients,  nitrogen and phosphorus from the
 1968 survey is fairly high.   Total nitrogen averaged 0.58 mg/1 and
 total phosphates (as P)  averaged 0.12 mg/1.  Although algal blooms
 have been reported to occur  with regularity in the Lake,  there have
 been no reports of conditions resulting in fish kills or  other oven
 signs of extreme eutrophy.   It is suggested that these are yet to
 come.  In 1962, La Rivers described  the Lake as "literally a culture
 medium for all organisms in  the food chain—temperatures  are warm,
 nutrients plentiful and  fish growth  rapid" (6).  With the combination
 of present agriculture and the rapidly growing urban area around
 Reno and Sparks, Nevada, contributing nutrients in return waters
 and sewage to  the Truckee River complexed  with the effects of evaporation,
 it is certain  that the future water  quality of Pyramid Lake will suffer.

 The Future of  Pyramid Lake

 Preliminary estimates indicate that  continuation of existing water
 use practices  together with  projected nutrient inflows will cause the
 present nutrient levels  to nearly triple in the next fifty years.
 Algal growth is expected to  increase as a  result of increased nutrient
 loadings.   Increased primary productivity  in Pyramid Lake is expected
 to supply enough biodegradable organic  material to result in anoxic
 conditions in  the hypolimnion of  the Lake  within the coming fifty-
 year  period.   Limnological investigations  should be carried out  to
 monitor the Lake algae,  nutrient  and oxygen levels.   Control of  nutrient
 discharge  to the Truckee River may be necessary to arrest the rate
 of eutrophication of Pyramid Lake.   Controls  might include  tertiary
 treatment,  land  disposal, or diversion  of  effluents  to the  Truckee-
 Carson  Irrigation District.

 From  the  time  Pyramid  Lake was deprived of an outlet,  it  was destined
 to eutrophy and  became more  saline at a faster  rate  since it is  now
 the repository  of all  nutrients and  other  salts  which  are washed  in
with  the  tributary  flow.  Accepting  this premise,  water quality  control
 becomes  focused  on  means  to  reduce the  rate  at which such terminal
water bodies are  allowed  to  deteriorate.

Efforts have been made recently by the  Department  of the  Interior to
maximize  flow available  to Pyramid Lake while  satisfying  other
existing water rights.  A 1964 Task  Force  Report  (7)  to the  Secretary
of the  Interior  resulted  in  the formation  of  the Interior Committee
on Operating Criteria and Procedures--Truckee and  Carson  River Basins.

Due to  the  efforts  of the Interior Committee, the  coordinated operations
of the Truckee and Carson Rivers have been controlled by  operating rules
and regulations  instituted on October 1, 1967.  Additional water
reaching Pyramid Lake during  the first year following use of  the
operating rules has been estimated at between 73,000 and  125,000 AF.
The operating rules and regulations are set annually to provide the
flexibility to make needed changes and adjustments which would result
in better use of the water resources available.  Even though the current

water year (1968-69) is much above normal, an additional 40,000 to
60,000 AF has reached the Lake due to basin operation under the Interior
Committee operating rules this year.  Thus, it is apparent that con-
siderable progress has already been made in arresting the decline of
the Lake.  The Committee is optimistic that even though the water
budget for the Lake has not been balanced, further progress can be made.

In its efforts to provide a solution, the Interior Committee has
considered other approaches to the problem.  These include the possi-
bility of reducing  the evaporative loss by artificially mixing the
Lake or by the use  of monomolecular films.  Preliminary studies indicate
neither evaporation suppression approach appears feasible; mixing
indicates a  theoretical water savings during summer months but heat
storage is expected to increase winter evaporative losses; film methods
may be prohibited by the high winds on this high desert lake.  Studies
by the Interior Committee are continuing toward the development of a
long-range water management policy  for the Truckee and Carson Rivers
and Pyramid  Lake.

                               SALTON SEA


The  Salton Sea  is  an  inland  sink  in a low-lying desert  area  south  and
 east  of Los  Angeles,  California  (Figure  5).  The  230,000-acre  sea
 is  threatened with rapidly rising salinity  levels which,  if  uncontrolled,
 are  expected to  eliminate  the  currently  valuable  sport  fishery within
 the  next  decade.   The Sea has  a volume of 6.0  million acre feet  at
 its  present  water  surface  elevation of  about  232  feet below  mean sea
 level.   Fluctuating water  levels  and eutrophication  symptoms such  as
 dissolved oxygen deficiencies  in  deeper  waters,  discolorations,
 turbidity and odors caused  by  dense phytoplankton populations  are
 also major  Salton Sea problems.

 The Salton Sink Sea Basin,  which  in its  lowest part  is  278 feet  below
 sea level, was the site of a large lake  in Pleistocene  times called
 Lake Cahuilla.   Several geologic  histories have been written on  the
 Sink and the theories conflict regarding a possible  connection with  the
 Gulf of California.  One possible explanation is that the 8360-square-
 mile Salton Sea Basin was cut off from the Gulf as the Colorado  River
 extended its delta.  During the last century water entered the Sink
 from the Colorado River on several occassions forming a small sea
 first discovered in 1850's.  A 100,000-acre lake was formed in 1891
 through a connection between the Alamo River and the Colorado River.
 This water  evaporated rapidly and was mined for salt the following year.

 The "modern" Salton Sea was formed by floods in 1905-07 which cut
 through a channel which carried irrigation water from the Colorado
 River to the Imperial Valley.  The break in the channel was repaired
 by 1907 and since  that time the Sea inflow has been  controlled by

                                         -SAMPLING STATIONS
^m * J 1 "
Water surface elevation of the Sea as
shown Is 235 feet below mean sea

irrigation practice.  The salinity of the Sea has increased from less
than 4,000 mg/1 in 1907 to about 37,000 at the present time.  Salinity
levels approaching  ocean values have persisted for nearly 50 years while
water levels were rising.  Slightly higher salinities, up to 40,000
mg/1, were observed during the late 1940*s due to reduced inflow.
Salinity is increasing in the Sea now that water levels are more
stabilized.  See Figure 6 for historical salinity observations.

Published data are available on chemistry of Salton Sea waters, including
a review of ionic composition from 1907 to 1955 included in the Cali-
fornia Fish and Game Bulletin edited by Walker (8) and of 1964 sampling
efforts described by Pomeroy  (9).  Recent data show salt levels are
approximately equal to oceanic salinity although ionic composition is
somewhat different.  Salton Sea sulfates are approximately triple,
calcium about double and chlorides 20 percent lower than typical
ocean water values.  Oceanic  fish, barnacles, and algal species are
now  common in the Salton Sea.

Most of the drainage to the Salton Sea comes originally from  the
Colorado River near Yuma, Arizona, where waters containing about 850 mg/1
salt are diverted through a series of canals westward  to the  Imperial
Valley and Coachella Valley for irrigation use.  Drainage from irrigated
land collected in open field  drains  and  subsurface  tile drains is
channeled  to the Salton Sea.  Evaporation, transpiration, and vegetative
uptake of water applied  to  the  land  concentrate  the  salts in  the moisture
remaining  in the field soils.   The resulting drainage  is often 3  to
5  times as  saline as the  irrigation  supply and may  be  much higher  if
excess salts have accumulated in  the soil.  The  character of  this
drainage usually is of a  sodium-chloride-sulfate character  in contrast
to the sodium-calcium-sulfate supply.   Of  the  annual  5 million acre
feet imported  from  the Colorado River  for  use  in  the  Imperial and
Coachella  Valleys and  in  Mexico about  1.2 million  acre feet  is returned
to the Salton  Sea.  Evaporation losses  within  the  Salton  Sea  approximate
this annual  inflow.  Thus a hydrodynamic balance  exists.

The Salton Sea currently supports a  valuable  sport fishery  including
Corvina,  Sargo and  Bairdiella (Croaker) which  were introduced in 1948
 from the  Gulf  of  California.  These  oceanic  species have  thrived in
 the Sea  but are  not expected  to tolerate salinity levels  above 40,000  mg/1
 Physiology studies  conducted  by the  California Department  of  Fish and
 Game indicate  survival of eggs  and larvae  is  unlikely above that
 salinity.   Adults  may  be more tolerant.  Food  chain organisms,  of
which there are very few species in the Sea,  are not expected to
 tolerate any substantial salinity rise.  The  Sea is expected  to  pass
 the 40,000 mg/1 level  during the 1970"s unless a water quality
 control  plan is implemented.   Delays will only increase the magnitude
 of the control developments and their cost since salt buildup, currently
 estimated at 5.6 million tons per year, is proceeding at such a rapid
 rate in the Sea.





   18-r 300
   2 •
   O-1-   0

                           THE  SALTON SEA

Water surface elevations have been generally rising in the Salton
Sea basin in contrast to the falling levels described in Pyramid Lake.
Rising water levels have flooded out shoreside developments and forced
bulkheading and channelization projects in other areas threatened
with flooding.  The low angle of repose of the Sea bottom magnifies
the water level problems.  Drainage waters flooded the federal wildlife
refuge during the 1930's, and today this area is primarily managed
as a waterfowl resting area.

The Salton Sea is objectionably eutrophic and is characterized by an
overabundance of mineral nutrients, mainly compounds of nitrogen and
phosphorus, which produce intensive "blooms" of floating, microscopic
plants  (phytoplankton) in the upper levels of the water mass.  Wind,
wave action and currents distribute these planktonic algae throughout
the Sea.  The immediate visible results are discoloration and  reduction
of clarity of the water.  In addition, although phytoplankton  are
essential to  the ecological system of  the Salton Sea, death and
decomposition of large populations of  these algae often result in
temporary anoxic conditions, particularly in the deeper waters, and
subsequent production of obnoxious odors over extensive areas  of the
Sea.  Temporary anoxic conditions often occur in Salton Sea during
the  summer months,  commonly leading to fish kills and the disappearance
of other  animals that are  intermediate links in the biological food
chain of  the  Sea.   Mats  of decomposing benthic blue green algae which
are  torn  loose  from the  bottom  occasionally form rafts  of unsightly
and odoriferous  scum on the  surface of  the Sea, particularly  near shore.

Eutrophication symptoms  such  as these  were described  earlier  by Walker
and  co-workers  as  being  prevalent  in  the years  1954,  1955,  and 1956,
the  period  of their study  of  the  Sea  (8).  These conditions have  reduced
 the  aesthetic appeal of  the  Salton  Sea and  limited water  contact
recreation  such as swimming  although  fishing  activity has  probably
been stimulated by the productivity  of the  Sea.

 The  tributaries to the Sea carry high concentrations  of nutrients
 originating from agricultural drainage and  sewage  from the  Imperial
Valley and  from Mexico.   The major  tributaries  averaged approximately
 0.5 mg/1 total phosphorus and 7 mg/1  total  nitrogen,  primarily in the
 nitrate form.  See Table 1 for details on nutrient content of sources.
 These sources discharge approximately 1  million pounds  of phosphorus
 and 25 million pounds of nitrogen annually to the  Salton Sea.

 Salton Sea Water Quality

 Field measurements and water samples were collected on the Salton Sea
 between July 1968  and May 1969.  These data serve to document  the
 present quality of the Sea, its tributaries and the nature of  any
 water quality problems.  Sampling stations are shown on Figure 5.
 Samples and field  data collected included nutrient samples at  several
 depths at each station, profiles of dissolved oxygen, pH, temperature

                                  TABLE  1

Alamo R.
NO 2
•-N, mg/1
-N, mg/1
-N, mg/1
-N, mg/1
, mg/1
, mg/1
New R.
Water R.
. 28*
CV Drains
           *Includes FWPCA and DWR data

observations of color, odor, transparency, light penetration profiles,
productivity measurements, chlorophyll and biological collections
including both plankton and benthic life.  Extensive salinity data
were not collected since the mineral content of the Sea has been
documented; limited mineral data gathered confirmed that Sea salinity
has passed ocean values and is high in sulfate.

The mean total phosphorus and total nitrogen concentrations for the
Sea during the study period were 0.07 and 3.30 mg/1 respectively.
Seasonal data are tabulated in Table 2.  A nutrient budget of the Sea
indicates that, on the average, about 45 million pounds of nitrogen
and one million pounds of phosphorus are present within the Sea waters.

Nitrogen forms within the Sea are predominantly organic in contrast
to the inorganically rich tributaries.  Inorganic nutrients entering
the Sea are converted to organic matter through photosynthetic processes
Nutrient levels in Salton Sea bottom sediments also reflect the high
organic content of the sea waters.  Sediment samples collected by
dredge and coring devices contained about 5 percent organic carbon,
0.3 percent organic nitrogen and 0.1 percent total phosphorus.

Data from field and laboratory studies of the Sea in 1968-69 also
provide further documentation as to the seriousness of fishery problems.
Extensive fish kills of species such as corvina and gulf croaker were
observed in the Sea near the Whitewater River inlet on two separate
occasions and  dead mullet were seen near the Alamo River on one occasion,
Observations of dead fish were commonplace throughout the Sea.
Extremely unpleasant odors were also encountered; these were especially

          TABLE 2


N03-N (ing /I)
N02-N (mg/1)
NH3-N (mg/1)
Org.-N (mg/1)
Total N (mg/1)
Ortho P (mg/1)
Total P (mg/1)
pH (units) *
Temperature °C *
Transparency (feet)
Euphotic Depth (ft)
* Surface

7 .3




prevalent  near  shore,  often  at  the  sites  of  marinas  or  popular  fishing
grounds.   Strong  odors,  especially  the  rotten  eggs  smell  characteristic
of  hydrogen  sulfide  (lUS) were  often  noted and were  nearly  overpowering
in  the Whitewater River  area at the  time  when  one of the  extensive
fish  kills was  observed.  A  level of  H^S  lethal to  fish or  other
animals could very well  have been present in the water  on that  occasion.
High  H2S  levels were also reported  in May 1969.

The density  of  algal populations in  the Salton Sea  at times was so
great that the  water was highly discolored,  varying  in  hue  from a
brick red  in some areas  to brown and  light green in  others.   Examination
of  these water  samples indicates that the brick red  color was probably
due to dinoflagellates,  brown by diatoms  or  fish eggs and green by
green flagellates.  The  Sea  water was always somewhat colored and
always turbid.  Secchi disc  readings  averaged  about  one meter varying
from  about .5M  to 2M;  euphotic  depths were approximately  triple
Secchi disc  values.

Dissolved  oxygen  (DO)  concentrations  in the  euphotic zone _' were
invariably supersaturated during daylight hours, sometimes by a factor
of  200 percent  reflecting trie incentive r^r.o .osyncr.e tic  activity of  the
massive phytoplankton  population.

Dissolved  oxygen  measurements in the  Sea  at  depths below  the  euphotic
zone  (15 feet and below) for  the months of July-November  show that
the DO concentration often drops to dangerously low  levels, at times
near  zero.   See Figure 7 for  some representative profiles.  Extensive
regions of the  deep water during these months  often  contained less
than  3.5 mg/1 of  oxygen during  daylight hours.  Lower concentrations
occurred at  night when oxygen inputs  from photosynthetic  oxygenation
were  absent.  Water temperatures varied from 29.5°C  in  summer to
14.2°C in  winter;  pH levels  ranged from 7.3  to  8.8,  the highest values
being observed  in surface waters during May.

Comparisons  of organic production from other fertile waters show that
maximum levels of primary production  are  often  similar  in different
physical environments due to  light limitations.  Production of phyto-
plankton algae expressed as  gms Carbon per square meter per day may
be the same  in a  100-ft. deep euphotic zone  in  the ocean  and  in a
5-foot zone  in an enriched murky bay  made turbid by  the phytoplankton
themselves.  A plateau of maximum organic production is reached in
highly eutrophic  waters as a  result of this  self-limiting effect.
This  phenomenon is illustrated  by Figure  8.

Odum has classified production  rates  for  various ecosystems and shows
maximum values of  1.0 gram of carbon  fixed per  square meter per day
for oligotrophic  (nutrient poor) lakes and oceanic areas  (10).
       2] The euphotic zone is often defined by the depth which sunlight
sufficient for photosynthesis occurs—of ten this is approximated by
the depth at which light energy equals 1 percent of surface  light intensity,


                  DO ( mg/I)
                                       DO  (mg/l)
      024    6    8    10  _ 12   0     2    4^6






10    12    14    16    18    20   22   16    18

                           DEEP   STATION

       10    12    14    16
                18   20    22    16    18

                   SHALLOW STATION
                                                    20   22   24   26
                                              20   22   24   26

                               SALTON  SEA

a: o
S <°


O -1
z o:
o <
»- H

o a:
cr u
a a.
                          /—NATURAL  EUTROPHICATION
                          AGE OF THE LAKE
        Nott: Adapted from Hosier, A. O. Eutrophicotion of Lakes by Domestic

            Drainage, Ecol ^8<4)I947

                      SALTON  SEA STUDY

Shallow, eutrophic lakes are expected to produce up to 5 gms C/m
day; values over 3 gms C/m^/day in aquatic systems are considered high.
Measurements of primary production in the Salton Sea during 1968
averaged about 3.0 gmC/m2/day and exceeded 5 gmC/m2/day, on several
occasions.  These high productivity values are in the range expected
in the shallow, nutrient rich Salton Sea.

The Future of the Salton Sea

A salinity control plan is undergoing study by agencies of the Department
of Interior and the State of California.  A reconnaisance Report, to
be published by the Bureau of Reclamation in 1969 will outline al-
ternative salinity control plans.  Earlier studies by Pomeroy considered
the use of large evaporation ponds formed by diked areas within the
Sea  (10).  Such a scheme provides a salt outlet through salt extraction
from  solar evaporation, thus stabilizing the salinity of the Sea.
If  such a method were employed,the resulting salinity level of the
Sea would depend on pond size and the timing of such a project.

The nutrient content of the Sea is not  greatly different from the
computed annual inflow; yet comparable  annual loads of nutrients have
been  entering  the Sea for decades.  Soluble forms  such  as NO-j have
not built up in the Sea over the past decades, but rather have been
converted to phytoplankton  in the warm,  shallow sea  later to be
deposited as dead organic matter on the sea bottom or consumed by
 predators  within the sea.  An  equilibrium  is maintained wherein
entering nutrients are  assimilated by the Sea's ecological  system  or
deposited  into the rich bottom  sediments.   Only a  relatively small
 fraction of  the nutrients which have entered  the  Sea  over  the years
 are maintained in the water phase.

Fish harvests,  although  sizeable,  cannot account  for  these  major changes
 in  nutrient  level; for  example, annual  harvest  of  100 Ibs.  of fish
 per acre would remove  slightly  more  than one  half  million  pounds of
 nitrogen  or  about  2  percent of  the  annual nitrogen load (based  on
 2.5 percent  nitrogen in fish  flesh  by wet weight).   The estimated
 Salton Sea  harvest rate was about  six pounds  per  acre in 1966.

 In  summary,  the nutrient related problems of  the  Salton Sea are those
 expected  in highly  eutrophic  waters.  The enrichment of the water
 phase is  probably as advanced as is likely  in this inland  sink  where
 nutrient  trapping and the dynamics of  the eutrophic  ecosystem have
 subdued the fertilizing effects of the  rich tributaries.   While
 salinity  increase is the most pressing  water  quality problem and a
 task force comprising agencies of the  State of California and the
 Department of Interior is evaluating salinity control plans, work
 is  also in progress  on plans for water  level  stabilization, nutrient
 control and ecological protection for  the Salton Sea.


The problems of Pyramid Lake, Nevada, and Salton Sea, California,
are similar in many ways and are common to othpr inland sinks.
Salinity increases and water level fluctuations attributable to water
and salt inflows and evaporation losses may be controlled or abated
through river basin and water quality management schemes.  Pyramid
Lake water levels and the rate of salinity increases can be controlled
by increasing the water supply to the Lake.  Salton Sea salinity and
water level problems can be better controlled by salt extraction,
lower irrigation efficiencies in nearby agricultural areas, bulkheading
on developed parts of the shore, and possible future evaporation
pond operation.  Eutrophication symptoms, advanced in the Salton
Sea and emerging in Pyramid Lake, are less easily manipulated.
Natural forces of deposition and consumption of organic matter within
these waters will tend to limit nutrient buildup; however trapping
and predation effects alone will not eliminate algal blooms.  Control
of eutrophication must begin with control or elimination of major
nutrient sources.

Although the quality of both the water bodies discussed is far from
"pristine," nonetheless both are economically valuable water resources.
The future of either is uncertain;  however, it is clear that unless
water quality control measures are taken, both will eventually become
aqueous deserts.  The problems of these two desert lakes are recognized
both locally and nationally.  Local,  State and Federal efforts are
underway to preserve or enhance the water quality and associated uses
of these two inland sinks.


1.  HARDING, S. T.  1965  Recent Variations in the Water Supply of the
    Western Great Basin.  University of California Archives Series
    Report No. 16, pp 226.

    Water Resources Data for Nevada, p. 114.

3.  NEVADA FISH AND GAME COMMISSION.  1968.  Data Tabulation received
    from T. J. Trelease.

    Survey of Pyramid Lake, Oct. 1968.

    Evaluation of the Lahontan Cutthroat in Eight Mile Lake, Carbon
    County, Wyoming.  Administrative Report.  March.

6.  La RIVERS, IRA.  1962. Fishes and Fisheries of Nevada.  Nevada
    State Fish and Game Commission.

7.  U. S. DEPARTMENT OF INTERIOR, TASK FORCE.  1964.  Action Program
    for Resource  Development, Truckee and  Carson River Basins,

8.  WALKER, B. W.  1961.   The  Ecology of the  Salton Sea, California,
    in Relation  to the  Sport  Fishery, California Department of  Fish
    and Game.  Fish Bulletin  113.

9.  POMEROY,  R.  D. and  CRUSE, H.    A Reconnaissance  Study  and Preliminary
    Report  on a  Water Quality Control Plan for the Salton  Sea.
    Prepared  for the California  State Water  Quality  Control Board,
    December  1965.

10.  ODUM,  E.  P.   Fundamental  of  Ecology, W.  B. Saunders Company,  1959.



                            John M. Neuhold I/
If pollution is a degradation of the environment as a result of man's
activity in it, and if man is considered to be apart from the natural
environment, then the terms natural and pollution are clearly con-
tradictory.  In this paper I explore the meaning of natural pollution
as it might apply to an arid lands water system, generalize a definition
for this pollution and speculate on the possible consequences of the
pollution thus defined.  The water system we will consider will be
limited to the surface waters in arid lands, since these waters most
obviously reflect the effects of the meteorological contribution from
the hydrological cycle.

Characteristics of Arid Land Waters

Arid lands are characterized by a precipitation-evapotranspiration
ratio that favors evaporation.  Under these circumstances, shallow,
standing bodies of water with a large surface area are not favored
except  in endorheic basins where the input of surface water from the
watershed is at equilibrium with evaporation from  the surface of the
basin.  Such a permanent body of water  is essentially a function of  the
size of the watershed and characteristics of the catchment basin.

Aside from permanent bodies of water in endorheic  basins, surface
water in arid  lands exists primarily as streams or rivers.  The water-
sheds are chacterized by shallow soil development  and low vegetative
cover,  a situation that favors substantial  surface runoff.  Sustained
flow in water  courses in arid regions is  the result of melting snow
packs at higher elevations or of sub-surface water flows  in deep aluvia
or deeper aquifers.  Because of the high  degree of surface runoff when
precipitation  does occur, waterflows in the  streams are marked by
violent fluctuations  in volume.  In the higher  order  streams,  they
can range from nothing to  floods,  and in  the  lower order,  sustained-
flow streams  it can range  from  low, clear flows to high,  turbid  flows.

Because of  their  relatively  low mechanical  stability, soils  in arid
lands are highly  susceptible  to erosion.   During  periods  of  precipitation,
therefore,  the surface flow  is  usually  loaded with relatively  high
concentrations of particulate matter which in  turn increases  the
corrosive  quality of  the water, and  its turbidity.  High  evaporative
losses  result  in  a concentration  of  solids dissolved  from the  geological
formations  making up  the watershed and  the silt loads carried  by
the  runoff.   In general,  the  sustained  water flows in arid lands are
        !_/  Director,  Ecology Center,  Utah State University, Logan.

characterized by  violent  fluctuations  in water  level,  high  turbidities,
and a relatively  high proportion  of dissolved solids.   Down stream,
salt concentrations  and water  temperatures  are  increased while
fluctuations in silt  loads  and waterflows are modulated.

An ecologist cannot  discuss  any aquatic system  without also mentioning
its biological system.  Every  environment in the earth's biosphere
has a life  system of one  form  or  another developed  in  it.   Waters
in arid  lands are no exception.   The remarkable thing  about the  life
systems  in  arid land streams are  their adaptive qualities.   Not  only
is each  life system  geared  to  the violent changes in quality, but
the individuals making up that system  are morphologically adapted
to sustain  themselves under  these violent changes.  Fish, for example,
are morphologically  adapted  to cope with torrential flows and corrosive
silt loads.  They are also  physiologically  adapted  to  handle sudden
changes  in  temperature and  salt concentration.

Aquatic  insects,  the predominant  herbivores in  the  system,  are likewise
adapted  morphologically and  physiologically with timed stages of their
life cycle  to "fit"  the demands of the system.  The primary producers
of the system, the algaes and diatoms, are  perhaps most susceptible
to changes  which  occur.  The scouring  action of silt-laden  waters
makes life  for the primary  producers somewhat tenuous.  Although  it
is not unreasonable  to assume  that a significant amount of  primary
production  does occur in  these waters, it is also likely that terrestrial
sources  supply quantities of organic materials  via the surface runoff.
In any case, biological systems are important in arid  land  waters,
particularly relative to pollution, since it is the biological system
that first  shows  signs of the effects of that pollution.  The aquatic
system thus is characterized by a specifically  adapted biological
system that is a  living, cycling  pool of organic matter and nutrients,
and may  serve as  an  indicator of  pollution.

Uses of  Arid Land Waters

Because  of  the scarcity in  arid lands, water is much sought-after
for both consumptive and non-consumptive uses.  Predominant uses
include  irrigation,  power generation,  stock watering,  community,
industrial, recreation, and navigation.  Each of these uses has  a
unique set  of water-quality  requirements.   Those irrigating crops
and watering stock,  for example,  are concerned  with the type and
quantity of salts.   Power generation and navigation usage require
certain  flow regimens.  Culinary  and industrial use must consider
the economics of  treatment.

Pollution Defined

The subject of this  discussion is natural pollution in arid land
waters.   Pollution is variously defined depending upon man's use or
nonuse of the water.  But most definitions  agree that  pollution  implies a

change in quality as a result of man's use.  Similarly, the term
natural can be variously defined.  It can include or exclude the
influence of man.

The "I - Thou" Definition of Pollution

Since man is an inextricable part of the biosphere and must be
incorporated into any consideration of ecosystem dynamics, I prefer
to look upon natural pollution as including his effects.  However,
since he is rational and in potential control over his actions, his
effect in the natural system must be given a set of continuously
variable values dependent upon the state of his technological
development.  The most natural system, then, would include man in a
hunter-gather culture, whereas the least natural system would have
him in a high state of technological development.

Most conservationists would treat the natural environment as a dis-
continuous variable.  Under their interpretation, natural pollution
could only be contributed by catastrophic geomorphic and meteorological
events.  The only criterion for measuring that pollution V7ould be
a change in the precatastrophe ecological system.  Such events could
include volcanic activity, sudden and abrupt faulting resulting in
changes in water courses and sudden and abrupt changes in weather
patterns.  Man's role in the environment defined as most natural
is relatively minor.  He serves as a top carnivore with a limit to
population size dependent upon the production of the land area.

Development toward  an agrarian-herdsman culture results in an  increas-
ingly intensive use of land by man, with concomitantly increasing
effects upon the waters of that region.  More use of the watershed
by grazing animals  under man's control, and his development of culti-
vation and irrigation practices increase erosion probabilities and
thus  the silt loads of the streams.  Irrigation  increases  the  total
dissolved solids in the waters returned to  the natural system.  In
addition, human populations densely congregated  and their associated
effluents become more of a factor in the ecosystem.

If we follow the development of man into an industrial culture, we
find  additional uses of the  lands including extraction of mineral
resources from the  watersheds,  intensification of man's activities
on those watersheds, and more conditions conducive  to  changes  in  the
quality of water in the area.

At the existing  state of technological development, man's use  of  an
ecosystem becomes more pervasive  through the adding of contaminants
to the atmosphere,  which in  turn  are precipitated upon watersheds
and contribute qualities to  that watershed  previously not present.
These eventually are reflected  in the stream collecting systems.
For example, consider chlorinated hydrocarbons,  which  though used
primarily in areas  quite remote  from arid  lands,  can  find  their way
through meteorological sources  onto the watersheds  and  eventually
into  the  streams.


As  I  am defining natural  pollution,  it  is  a function of the state  of
technological  development of  the  human  population on earth.  Man is
part  of the  system.   Taking Martin  Buber's words, man is the "I" and
the environment  is  the  "Thou."  Note that  pollution is considered  to
be  whatever  is added  to the water that  causes  a change in the ecological
system developed there.  This definition admits man into the system
and allows  for the  development  of a naturalistic ethic that man is
fully capable  of imposing upon  himself.  In other words, as an ethic
is  developed,  the effect  of technology  may be  reduced and the eco-
system becomes the  true criterion for pollution identification.

The "I - It" Definition of Pollution

If  any ethic has developed however,  it  is  founded on the egocentric
viewpoint of material gains from  watershed and water (man is the "I"
and the environment is  the "It").   Thus  our definition of pollution
must  incorporate the  use-oriented value  system.   In other words, water
can or cannot  be polluted relative  to the  use  to which it is put and
not relative to  the system (including man) that has developed under
most  natural conditions.   Therefore,  if  arable lands are available
at  the terminal  ends  of arid  land systems,  but the  water arriving  there
is  too salty for irrigation use,  the water is  polluted in relation
to  that potential use.  Or the  water  is  polluted when it is too  silty
for industrial use  even if the  water at  that point  in space and  time
had received its salt and silt  loads in  a  "natural" way.

In  this context,  "natural" is considered to be any  influence on  water
quality not  caused by man.  Salty water  from springs,  silt from  pristine
watershed, wildlife fecal contributions  are examples of  "natural
pollution."  The problem  with this definition  of natural  is that
natural salt springs  contribute insignificant  amounts  of salt to the
surface water, pristine areas no  longer exist  and no population  of
wildlife has escaped  the  influence of man.  For  example,  some duck
populations  around  the  Great  Salt Lake are  several  magnitudes greater
in  numbers now as a result of marsh management and  agriculture,  than
they  were in early pioneer days.  Certainly, the nitrogen input  into
the marshes  via  duck  droppings  has also been increased.


There  is  virtually no arid land in this world  that  does  not support
some  form of man's activity.  Certainly  irrigation  technology has  been
widely  applied to arable  lands.   Stock raising predominates  over great
portions  of  arid  and  semi-arid  watersheds.  Many of  the  arid  lands
are also  rich  in  minerals  and other geological deposits  of value to  man,
and therefore  mined.  Man's activities in  arid  lands  require  road
construction;  therefore,  surface disturbance results.  Power  generation
requires  the construction  of dams on the rivers  and  these  change the
quality of the water  below the  dam as well  as  above.   In  the  context
of our  first definition of natural systems, these activities  produce
a  semi-natural type of  pollution  that nonetheless falls  into  the
category of natural.


Despite technological development, arid lands in North America are
still sparsely populated.  Intensive agriculture and industry and urban
settlement involve only small portions of the total arid land use.
However, whatever water is present in such areas is sure to be polluted
regardless of the definition used.  Any additional use of an arid land
watershed produces materials sufficiently different from that which
would have occurred under the existing use to qualify as pollution.

From geological sources, one can expect increased concentrations of
salts of various  types, including the heavy metals and increased
turbities.  Mining activity brings minerals to the surface that
eventually may find their way into the stream courses and cause con-
siderable damage by producing toxic concentrations of elements that
are deleterious to the ecological system.  Certainly this occurs when
mined minerals are upgraded and the liquors of the upgrading process
are released to the stream courses.  Meteorological sources will bring,
in addition to the precipitation, airborne pesticides and other
organic and inorganic effluents of industrialization, some of which
may be in sufficient quantity to be toxic to components of the
aquatic ecosystem.  Grazing activities tend to reduce plant cover,
and if not managed properly can denude the watershed resulting in
increased erosion and subsequently increased silt loads.  Intensive
concentrations of grazing animals near watersheds produce quantities
of organic nitrogen compounds.  Irrigation use of water results in
increased salt concentrations of the returned effluents.  The lower
Colorado River provides  a good example of such phenomena.  All these
contributions to the aquatic system affect the "naturally" evolved
ecological system.  At the same time, they also  affect other uses
of the waters downstream.

Dams  constructed on the  main streams of  arid lands have done a great
deal  to reduce turbidities and regulate  flows.   The effects produced
on the ecosystem in the  forbays and on water quality  for  long stretches
downstream from the dams have been great.  The existing ecological
systems of these streams were essentially wiped  out and other systems
replaced  them.  Further, the dams have  allowed  the  lands  under their
influence to  accommodate greater  numbers of  people.   Greater numbers
of people, in turn, contribute more effluents  to their environment.
The net result has been  that  the  streams must bear  the effluents  from
that  increased population, which  affects  the area's newly developed
ecological system, man  included.

The  distinction between our  original  two definitions  are  important.
In the first, man  is  considered  part  of an  ecosystem  which he can
manipulate but only  to  the  limit  of  available  resources or  to  levels
of limiting  factors  before  collapse  of the  system results.   As Marston
Bates points  out,  man is part  of a continuous  and interrelated  network
of life  that  makes him as natural as  an algae.   What  affects the
 system affects him.   In the  second definition,  man sets himself apart

from the system.  He manipulates it to maximize his immediate economic
gain.  In the first, an ecological ethic of land and water use is
inherent.  In the second, it is nonexistent.

The ramjet  process of people begetting development begetting people
is limited in arid lands by the availability of water.  Unless an
ecological ethic is developed and implemented by man for the use of
these waters and the associated land areas, man may find himself to
be the factor limiting his own existence.


Bates, Marston.  1960.  The Forest and the Sea.  Random House, Inc.

Buber, Martin.  1958.  I and Thou.  Charles Scribner Sons.



       Allen Cywin, George Rey, Stanley Dea, and Harold Bernard •!•'
The use of distillation as a means of producing high quality water
in arid regions has previously be.en limited to applications using
saline waters as a feedwater supply, either from brackish ground
water or the ocean.  Another potential source of distillation feed-
water in arid regions which should not be overlooked and may be
useable for distillation processes is the wastewater effluent from
secondary municipal sewage treatment plants.

Conceptual arrangements of how distillation may be used in wastewater
renovation schemes center about the concept of wastewater recycle.
Typical systems have been outlined by Hickman (1) and Stephan (2).
Both systems are based on'recycling for potable water reuse, some
or all the municipal effluent from biological secondary treatment
plants.  These proposed systems are still conceptual, and remain to
be demonstrated.  The system proposed by Stephan is shown in Figure 1.
Here distillation is used in a split flow manner in order to provide
the salt removal capability required for continuous water recycle  for
potable reuse.  In this plan pretreatment requirements before distillation
were not identified in detail.

An alternate to the potable water reuse plan by recycle would be the
production of  low mineral content water for industrial purposes,
particularly for those industries which require  such water  in  large
quantities.  The scarcity of low mineral content water in many  of  our
arid regions currently requires high treatment costs for the water
sources available, if such  treatment is not applied excessive maintenance
costs  for machinery, boilers, piping, etc.  are  incurred.

A review of past studies  (3,4) suggests that with  the proper develop-
ment of a municipal  secondary effluent conditioning process, this
source of water may be suitable  for use as  distillation  process
feedwater.  This very possibly results in  less  costly distilled water
as compared to the costs  of conventional distillation processes using
saline water  sources as  feedwater.   In addition, a part  of wastewater
renovation costs can realistically  be attributed to pollution  control
requirements.   This  is particularly true in areas  where  tertiary
treatment of  effluents may  be necessary to  meet water quality  standards.
        I/ Respectively,  Director, Division of Applied Science and
 Technology;  Professional Engineer, Industrial Pollution Control Branch;
 formerly Section Chief,  Agricultural Pollution Control Section; and
 Chief, Agricultural and  Marine Pollution Control Branch, Office of
 Research and Development, Federal Water Pollution Control Administration,
 U. S. Department of the  Interior, Washington, D. C.


Total- 54^/1000 gal.

     Figure 1 - Water Renovation Scheme
Total= 57^/1000 gal

It is felt that for the immediate future, industrial reuse of municipal
effluents will take precedence over potable water reuse.  This is
particularly true in view of the water needs for industry as forecast (5,6)
In addition, reuse for industrial purposes would have less stringent
health and safety requirements to meet.


Renovating municipal effluents to meet the chemical requirements of
potable water standards can be accomplished by using tertiary treatment
processes for the removal of the remaining organic, ammonia, and
mineral constituents.  In some cases the use of a demineralization
step may even be avoided by blending tertiary-treated effluents with
a lower mineral content municipal water intake.  This approach was
outlined by Hickman (1) and can produce a product water of acceptable
mineral content in some cases.  Such a method effectively reduces
the mineral content of recycled water by dilution.

In addition to the possibility of renovating effluents  for potable
use, consideration should be given to renovating effluents for use
as an industrial water supply where a dissolved mineral content of
50 ppm or less is desired.  It should be realized that  the cost of
demineralizing effluents may well be competitive with the cost of
desalting brackish or  saline supplies by the use of distillation.
In fact, a  study by Gerster  (7), indicated  lower costs  may be possible
if the maximum operating temperature could be raised to 350° F.

Research on the problems and costs of using effluents have been under-
taken by the  Federal Water Pollution Control Administration  (FWPCA).
However, more development work, and engineering demonstrations are
necessary in  order to  give potential users  the necessary  assurances
needed to implement effluent wastewater  recycle or  reuse  for producing
high quality  water.

An  important  consideration  for  the attractiveness  of municipal
effluents as  distillation  feedwater relates to  the  sulfate  content.
Table  I  presents  average  sulfate concentrations  for various  types
of  potential  feedwater supplies  in arid  regions.   It  shows  that
wastewater  effluents  are  considerably  lower in  sulfate  content  than
either ocean  or  brackish waters.

The  lower concentrations  of sulfate  and  total dissolved solids  in
wastewater  effluents  will  permit  less  percentage  blowdown in a
distillation  system than with most natural brackish waters  and  far
 less blowdown than with seawater.  The net results will be  more  product
water  and heat  conservation.  Approximately 25% of the  feed in ocean
water  must  be used for blowdown versus an estimated 57. for  waste
 effluents because of  lower sulfate  and solids  contents.  Lower  sulfate
 contents of wastewater should also  allow higher operating temperatures
 to be  used  for  evaporation,  less  extensive sulfate scaling, and
 consequently  lower potential cost  of distillation per unit of water


                                  TABLE I

                         SULFATE CONTENT OF WATERS
                   Source                       Concentration, rag/1

    Ocean                                              2700

    Los Angeles - San Diego, Calif.                     300
    (Wastewater Effluent)

    Tucson - Phoenix, Arizona                        150 - 300
    (Wastewater Effluent)

    Buckeye, Arizona                                  50 - 1500
    (Brackish Supply)
Stephan's prior prediction (2) on the role of wastewater effluents
for reuse indicates that the highest cost of renovating effluents for
use in a water recycle plan is related to the demineralization operation.
If we were to assume a hypothetical secondary effluent wastewater with
a mineral content (TDS) of 850 ppm (City of San Diego, half of South
Dakota, etc.) and we require a water of 50 ppm or less (therefore a
removal of greater than 800 ppm), it is our estimate at this time
that distillation of wastewater could, for large scale use, be economical,
corapetetive or even advantageous in comparison with other sources of

Using a 10-20 MGD demineralization capacity as a study case, the total
cost of distilled water production is estimated to be about thirty-
six cents per thousand gallons of effluent used.  The cost includes
our best estimate of pre- and post-demineralization treatment require-
ments.  On the basis of this estimate, it appears the distillation
process should be considered for wastewater renovation to produce
industrial waters requiring less than 50 ppm of dissolved mineral
content.  In contrast, electrodialysis (ED), another method of de-
mineralizing wastewater, would be limited to producing water of about
300 - 500 ppm when used in an optimum manner (8).

In light of recent advances in thin-film distillation technology (9),
even further cost reductions may be possible.  Particularly if long
tube vertical (LTV) distillation is utilized.  For this type of plant
the blowdown ratio should be about 5% of the total flow when distilling
many municipal effluents.  The recent development in higher heat
transfer coefficients for falling thin-film evaporative surfaces is
comparable to increasing the permeability of existing membrane

demineralizing systems (ED or RO) by a factor of 3 to 4, with no
additional increase in power consumption or transfer area.  It should
be realized that this relatively simple development took some eight
years to become a reality in spite of the fact that it was known to
be theoretically possible for years prior to initiation of development

Also, to be given consideration is the quality of the distilled water
in terms of total dissolved mineral solids  (IDS) content.  It generally
is too good to blend into a lower mineral grade water supply, particularly
when low mineral content water is expensive to make and processes
for making it result in additional cost appreciably above the initial
supply used (assuming municipal water supply).  A further consideration
is that the projected demand for lower mineral content water is
increasing considerably (10).

If a distillation-dehydration process (11) were to be used for treatment
of municipal  sewage  sludges, 0.5% of the total plant wastewater  influent
could be recovered as a by-product distillate water.  In  such a  process
the heat required  for distillation would be obtained by  incineration
of the dehydrated  sludge.  This  example implies municipal sewage
wastewater has  sufficient recoverable heat  values to provide  some  of
the energy necessary to purify the per capita water consumption  demand.

Our  survey of sewage and refuse  heat values coincides with those of
Burns and Roe (12)  in which  the  heat values in municipal  wastes  (both
solid and liquid)  on a per capita basis was found  to be  sufficient to
distill  25% of the total per  capita water  demand.   The  energy involved
is nearly  (approximately  757,) enough  to demineralize  the  per  capita
wastewater effluent  from  850 to  550 ppm using distillation  in a  split
flow water reuse plan  (Figure  1).

Research and  Development  Requirements

In view of  the considerations presented  and initial studies  (3,4,7,13)
on the  application of  distillation to wastewater  renovation,  R&D work
with  distillation processes,  as  applied  to wastewater renovation,  should
be continued.  The work  of  0*Conner  (4)  is encouraging,  and  the  problems
 of ammonia  and volatile  organics identified in  the study may hopefully
be resolved  by further laboratory and pilot plant work.   In view of
 the  potential for obtaining higher heat  fluxes  in the use of LTV
 distillation vs. the multiple stage flash (MSF) system,  pilot plant
 or demonstration efforts  emphasizing the use and further development
 of LTV distillation systems is  recommended.  Particular attention
however, will need to be  devoted to the  feedwater pretreatment require-
 ments and operating conditions for the first stage effect.   Pretreat-
 ment systems generally include deaeration - decarbonation devices,  and
 in some cases, as for boiler water preparation, include hot lime
 softening within the deaeration operation.  Thus, developing the
 pretreatment system to provide for multiple functions and increased
 effectiveness for organic and ammonia removal should be possible.

For example,  as  shown  in Figure  2,  a  countercurrent  steam  stripping
deaerator could  result  in producing the  same  chemical effects  as  the
"hot"  lime process and  thus precipitate  temporary  calcium  hardness
as calcium carbonate while stripping  carbon dioxide, oxygen, and
volatile organics.  The carbonate precipitation naturally  softens
the water but also can be expected  to coagulate and  remove suspended
and possibly  dissolved organic matter on clarification.  This  should
reduce organic contamination of  distillate further than that reported
by O'Connor and  thereby further  reduce the ammonia reportedly  generated
by the hydrolysis of organic matter in the still bottoms.

It should also be obvious that secondary effluent  saturated with
temporary calcium bicarbonate hardness may be ideal  for treatment.
If insufficient  temporary hardness  is available, hot soda-lime processing
may be required.  Another lime process alternative would be the
"cold" lime process to precipitate  carbonate  and free carbon dioxide,
followed by stripping ammonia in a  deaerator  tower.  The incremental
cost for the  pretreatment system as discussed should be reasonable
since  the basic  operations performed  are akin to the requirements
for preparing distillation feed  and is standard practice in many
boiler feedwater preparations.   In  case  the ammonia  in the effluent
is not stripped when treated, nitrification of the ammonia in  the
effluent can be  included as a requirement of  the preceeding biological
treatment operation.  Some work on  the development of this pretreatment
technique to  the extent necessary to  permit its employment with the
LTV distillation process is currently being initiated.

Total Treatment Costs

Total cost estimates for renovating municipal secondary effluents
into a high grade industrial water  supply are as follows:

                                                  Total Cost ^/lOOO gal.
A.  Pre-Treatment                                    10 - 20 MGD Scale

    1.  Nitrification                                  1

    2.  Hot-Lime-Deaeration stripping and              2
        clarification  (incremental  increase
        over existing)

B.  Demineralization

    Un-0ptimi2ed (15 MGD) LTV (4)                      30   (1961 Cost basis)

C.  Post Treat & Disposal

    1.   Aeration                                       1

    2.   Chlorination                                   1

    3.   Brine disposal                                 1

                                       TOTALS         36^


         CaC03  -  ORGANIC
(1)   Hot Ltme  Treatment   Ca(HC03)2
(2)   Soda-lime Treatment Ca SO^+Na CO —

(3)   Cold Lime Treatment Ca(HCO )   + CaO
                                                Na SO +CaCO
             Figure 2 - Distillation Feedwater Treatment

Pre- and post-demineralization treatment costs are included based on
our best estimate of technical requirements for successful operations,
The "hot lime" operation as a distillation pretreatment step assumes
a substantial reduction of the organic matter in the feedwater would
occur.  Nitrification assumes essentially a complete conversion of
feed ammonia to a stable nitrate salt.


On the basis of this literature review we believe -- "A New Look at
Distillation" (14), is in order in arid regions faced with providing
low mineral content waters for industrial uses.


 1.  Hickman, K. C. D., "Role of Distillation in a Treated Waste
     Recovery Cycle."  Jour. American Water Works Association,  55,
     1120-1130 (Sept. 1963).

 2.  Stephan, D. G., "Renovation of Municipal Waste Water for Re-Use."
     A. I. Ch. E., Jour. Chem. E. Symposium. No. 9 (1965).

 3.  "Advanced Waste Treatment by Distillation."  AWTR-7.

 4.  O'Connor, B., et al., "Laboratory Distillation of Municipal
     Wastes Effluents."  Jour. Water Pollution Control Federation
     (Oct. 1967).

 5.  "Why Water Shortages?"  Power (June, 1966).

 6.  Weinberger, L. W., et al., "Solving Our Water Problems - Water
     Renovation and Reuse." FWPCA, Dept. of the Interior (Aug.  1966).

 7.  Gerster, J. A., "Cost of Purifying Municipal Waste Waters  by
     Distillation."  Public Health Service Publication, No. 999-WP-6
     (Nov. 1963).

 8.  Harty, H., "Desalination of Sea Water: A Survey Paper." BNSA,  134
     (Apr. 1965).

 9.  Lotz, C. W. "Thin-Film Distillation."  Industrial Water Engineering
     (Dec. 1965).

10.  Calmon, C., "Water Purity in Perspective."  Industrial Water
     Engineering   (Oct. 1967).

11.  "The Choice is Yours."  Carver-Greenfield Corp. Brochure.

12.  "Use of Waste Heat for Production of Fresh Water."  OSW, Dept.
     of the Interior (Saline Water Conversion Report for 1965).

13.  Middleton, F. M., "Flash Evaporation for Sewage Distillation and
     Concentration of Wastes."

14.  Ahlgren, R. M., "A New Look at Distillation."  Industrial  Water
     Engineering   (Oct. 1968).
Additional References:

Anon,  "Ion Exchange Now Purifies Even Saltier Water." Chemical
     Engineering  (June 1965).

Brunner, C.,  "Pilot Plant Experiences in Demineralization of Secondary
     Effluent Using Electrodialysis."  Jour. Water Pollution Control
     Federation^ Research Supplement (Oct. 1967).

Cywin, A., "Saline Water Conversion and the Demonstration Plant
     Program." ASME, 60-SA-24.

Kunin, R., "A New Ion-Exchange Desalination Technique."  First
     International Symposium on Water Desalination, Washington, D. C.,
     October 3-9, 1965.

Office of Saline Water, "Cost of Large Electrodialysis Plants."  Dept.
     of the Interior (Saline Water Conversion Report for 1965).

Schmidt, K. A., and Odland, K., "A New Ion Exchange Process for
     Economical Brackish Water Desalination." Presented ACS Div. of
     Water, Air, and Waste Chemistry, Detroit, Michigan (Apr. 1965).

Sturla, P., "Demineralization of Brackish Waters by Means of Ion
     Exchange. " First Internation Symposium on Water Desalination,
     Washington, D. C.  October 3-9, 1965.



                            Anthony V. Resnik
                          John M. Rademacher —'


The feeding of livestock in confinement has created a new major
industry.  Having become firmly established in the United States by
the late 1950's, it continues to rapidly expand.  During the emergent
stage, designers of cattle feedlots selected sites based primarily
on two criteria:  drainage and accessibility.  The lots were situated
on the nearest draw where the rains could scour the waste materials
from the lots into nearby gullies and streams.  Since, traditionally,
animal wastes were considered as "natural" or "background" pollution,
control measures were not implemented.  In the absence of positive
control measures, pollution of the surface waters resulted.  Now it
is known that animal wastes contaminate water supplies, destroy fish
and aquatic life in streams, and generally degrade water quality.
More important, it is also known that animal wastes are a controllable
major source of water pollution necessitating immediate attention.

However, there are still gaps in our knowledge concerning the most
efficient, effective and efficacious means of controlling pollution.
This will require that we delineate specific research needed relative
to the expected trends of the feedlot industry.  Not only must this
research answer the most pressing present problems, but also must be
simultaneously part of long range plans for developing sufficient
technology to control feedlot pollution 5, 10, or 25 years from now.
For instance, the interregional adjustments (shifting of location),
size, density and other factors are of vital importance in planning
research activities.  We must, as accurately as possible, project
these adjustments.

Prevention and control of animal waste pollution cannot wait while
all the data are collected and assembled.  To wait for all the answers
before taking action would squander time that we do not have.  To
wait may mean the degradation of many waters beyond the point of
recovery with accompanying health hazards of undefined proportions.
To quote Robert H. Finch (1), "echoing Aristole, that the ultimate
end....is not knowledge, but action.  To be half right on time may
be more important than to obtain the whole truth too late."
       \l Sanitary Engineer and Director, respectively, Missouri
Basin Region, Federal Water Pollution Control Administration, U. S.
Department of the Interior, Kansas City, Missouri.

Increased control  is  imperative now.  To date,  the kaleidoscope  of
alternatives  to  animal waste pollution control  have been honored more
fully  in principle than  in practice.  Feedlot runoff  could be greatly
reduced with  a minimum expenditure by utilizing known information.
The majority  of  feedlot  operators have not  used techniques which
minimize the  quantity and strength of runoff waste.   For instance,
research has  shown that  feedlot runoff may  be reduced by adjusting
stocking rates and utilizing optimum feedlot surfaces (2,3).  What
does the future  portend?  Is it possible that animal  wastes and  city
garbage disposal may  both be operated on a  public utility basis  (4)?
Furthermore,  is  this  the mechanism to bring together  an entire animal
production unit  to research methods for the utilization of these

A much broader view of waste management may be  dictated by socio-
economic changes.  While the return of the  wastes to  the land may
not be competitive with  commercial fertilizers  on an  immediate crop
production basis,  it  may be highly profitable in terms of public
welfare over  both  the short and long range  to use these wastes to
reclaim marginal lands.  We are losing approximately  a million acres
of agricultural  land  each year as a result  of urban growth, highway
construction, and  other natural and man-made incursions into the
reserve of productive land (4).  It is difficult to equate the true
worth  to society for  the reclamation of lands.  Certainly it extends
much beyond the yearly crop production.

The residents of the  arid and semi-arid regions realize the value of
water.  Ground water  in  the semi-arid regions of the  Southwest is
being  mined at an unprecedented rate.  For  example, in some areas
of Arizona the water  table is declining as  much as 20 feet per year.
In many locations the quality of the water  deteriorates as the water
table  lowers.  Much of the water now pumped in  Central Arizona does
not meet minimum agricultural and public health standards (5).   Since
the agricultural industry consumes the overwhelming portion of the
water  used, it has the greatest stake in protecting and enhancing
water  quantity and quality.

                            ANIMAL PRODUCTION

There  are approximately 110 million cattle  in the United States.
Dairy  cattle outnumbered beef cattle in this country  until 1942.
Since  that time the upward trend in beef consumption, the downward
trend  in milk consumption per capita, and the upward  trend in milk
yield  per cow have combined to shift this cattle population emphasis
to almost four to one in favor of beef — in just 25  years!  Approx-
imately one-half of the two billion tons of livestock wastes produced
annually in the USA comes from animals in confined feeding.  The
magnitude of the problem caused by feedlot  operations is reflected
in the statistics for feeder cattle.  Data  compiled by Loehr (8)
show the waste population equivalent of feeder cattle is greater than
the human population  in 17 of our 50 states.

The Missouri Basin  States  of  Iowa, Nebraska,  Colorado, Kansas, Missouri,
North Dakota and  South Dakota,  feed  approximately  50  percent  of  all
slaughter  cattle.   Iowa  leads  the Nation  in  the number of  cattle and
calves on  feed.   In 1967,  more  than  4 million beef cattle  were marketed
from Iowa  feedlots.   The majority of the  cattle were  in .small farm
feedlots.  Only four  percent were in feedlots of more than 1,000 head  (9)
Nebraska ranks second with approximately  35  percent of the fed cattle
in feedlots of more than 1,000  head.  Third  is California,  with  an
average of 1,800  head per  feedlot.   There was an 87 percent increase
in cattle  marketings  in California between 1957 and 1963 with virtually
all the growth occurring in feedlots with 10,000 head or more capacity.
Texas, Colorado and Kansas, respectively, rank fourth, fifth  and sixth.

The new glamour area  for cattlemen is the Central  and High Plains
areas, including  parts of  Kansas, Nebraska, Colorado, and  the panhandles
of Oklahoma and Texas.  A  recent survey (1968) conducted by the
Southwest  Public  Service Company of Amarillo, Texas,  enumerates  274
large commercial  feedlots  in a  42 county area in Texas, Oklahoma, Kansas,
and New Mexico.   They have  a total one-time capacity  of over  1 million
head -- 300,000 more  than  the year before and almost  a half-million
more than  in 1966 (10).  The Texas High Plains has become  the center
of the rapidly expanding cattle industry, experiencing a remarkable
146 percent increase  in cattle  inventories between 1965 and 1968.
Fed cattle inventories for  the  State increased 66 percent  in  the  same
three year period.  The exceptional growth of the cattle industry on
the High Plains is  attributed to an availability of feed,  adequate
supplies of feeder  cattle,  an adequate transportation network, rapid
growth of  irrigation  wells, and a favorable climate.  Livestock  feeders
state that cattle performance is better at higher elevations where
summer nights are cool and humidity is low (11).

Surveys reported by Colorado, California and  USDA during the early
growth of  the commercial feedlot indicated that optimum feedlot capacity
ranged between 10,000 and  20,000 head.   Today 30,000  head capacities are
routine with 40,000 to 70,000 head lots becoming more prominent  in
the panhandle area  of Texas.  Thus, it becomes apparent that growth
is still a part of  this industry (13).   It has been estimated that
by the early 1970's,  approximately 2,500 large commercial feedlots
in the United States  will  supply nearly 70 percent of all the Nation's
finished cattle (10).  There does not appear  to be an optimum size
feedlot.   The continuous decline in costs with increases in size seem
to justify continued  increases  in the size of the lots.   However,
additional studies  considering both internal  and external costs of
operation  are needed  (12).  Studies to date have largely dealt  with
internal costs -- tax benefits, buying advantages, and other external
factors have not been fully evaluated.


The runoff from cattle feedlots can be  potent.  Miner, et al,  (3)
reported COD concentrations from 3,000 to 11,000 mg/1, ammonia nitrogen
concentrations ranged from 16 to 40 mg/1 and  suspended solids  ranged


from 1,500 to 12,000 mg/1.  These data provide a basis for an example
of the significant difference between population equivalent (PE)
values based on runoff and values based on manure production (10,14).

The oft cited PE values based on total animal production have little
meaning with regard to water pollution.  What we are really concerned
with is the amount that enters ground and surface waters.  If the
objective is to quantify the magnitude of the potential stream
pollution, PE values should be based on the strength and volume of
wastes which can enter a stream by storm water runoff rather than the
total manure production.  Dague (14) cites calculations, for a given
set of conditions, which demonstrate the BOD actually contributed
to the stream is about five percent of the total BOD production of the
animal.  Other investigators have made estimates of the total annual
pollution loads generated by runoff from feedlots.  These investigators
also demonstrated the quantity and strength of the wastes which enter
the streams to be considerably less than that defecated by the animals.
Let us now attempt to place this problem into perspective.

Sixty-six thousand feedlots, ranging in capacity up to 100,000 animals
blanket 7 of the 10 Missouri Basin States.  Animal wastes from the
more than 20 million cattle, 16 million swine and 7 million sheep
defecate wastes equivalent to 370 million people.  Using the previously
cited 5 percent figure, then the magnitude of the stream pollution
from animal wastes is more than 18 million PE in the Missouri River
Basin.  The human population of the Missouri Basin Region is 7.9
million.  Thus, the calculated stream pollution from animal wastes
is more than twice the human population equivalent.  We must use
caution in predicting and interpreting stream pollution from feedlots.
There are many variables which influence the effect of feedlot runoff
upon the receiving water course.  Among these factors are the climate
of the region and the area and nature of the feedlot surface.  Also,
the antecedent moisture condition of the accumulated waste and the
rate at which precipitation occurs are of primary importance in
determining the quantity and quality of runoff from a feedlot (2).
It has been noted by various investigators (2,10) that the greatest
pollutant concentrations are obtained during warm weather, during
periods of low rainfall intensity, and when the manure has been
dissolved by water soaking.

During warm, dry weather, especially in the semi-arid regions, the
most noticeable change in the deposited manure is evaporation of
moisture.  The wastes become pulverized by the hooves of cattle.  If
the accumulated waste on the feedlot floor becomes tightly compacted
and dry, it provides a relatively imperious barrier to the initial
rain, resulting in large quantities of organic runoff.  However, if
the accumulated manure on the feedlot floor is slightly damp when
precipitation begins, it can readily absorb a large quantity of
rainfall at a rapid rate, resulting in lesser amounts of runoff during
the early stages of the precipitation.  The dry, high altitude of the
Texas High Plains provides excellent drying conditions for the huge
quantities of feedlot wastes.  During the summer months, the moisture
content of the finely pulverized dehydrated feces and urine solids
may go as low as 2 percent  (2).


It must be remembered, however, that generalizations concerning
feedlot runoff are necessarily lacking in precision.  For example,
weather conditions alone can be quite important.  Data reported by
Kansas State University indicated all pollutional parameters greatly
exceeded previously measured values during a heavy rainstorm with
lot surfaces wet when the rain began.  Three inches of precipitation
fell during an eight-hour period.  Suspended solids were 26,850
mg/1 in samples taken 2-1/2 hours after the storm began and 4 hours
later were 45,200 mg/1 (10).


Since feedlots have generally been located without regard to the
soil inventory and topographic characteristics, surface runoff to
streams with subsequent damage from high BOD wastes is common.
Infiltration of nitrates from manures to well waters is well documented (6,7)
Field disposal of large concentrations of manures can lead to contamination
of underground supplies.

Field investigations of fish kills and other water pollution episodes
substantiate that the degradation of water quality due to animal
wastes is indeed a serious matter.  The release or runoff of these
wastes to surface streams during periods of rainfall produces "slug"
loads of the polluting material which can traverse the receiving
stream for many miles, kill all desirable aquatic life in its path,
disrupt or prohibit the use of the affected stream for water supply
purposes, and generally create public alarm (15).  The slug flow and
resultant adverse effects of animal wastes can be felt hundreds of
miles from their point of entry.  Spring rains in Kansas in 1967
washed tons of cattle feedlot wastes into receiving streams resulting
in fish kills and ruining the water supply of downstream towns (16).
Stream surveys were conducted on the Missouri River in June and July
of 1967 during and after a fish kill in the River.  The following data
were obtained (16):

       Kansas City, Missouri - The dissolved oxygen level dropped
       to 1.5 mg/1 in the river water, and was less than 4 mg/1 for
       11 days, and did not reach 5 mg/1 for 19 days.

       St. Joseph, Missouri - At times, the dissolved oxygen level
       was virtually zero and was less than 4 mg/1 for 7 days, and
       did not reach 5 mg/1 for 15 days.

       Jefferson City, Missouri - The dissolved oxygen content dropped
       to 2.1 mg/1 and was less than 4 mg/1 for 7 days and remained
       less than 5 mg/1 for almost a month.

The flow in the Missouri River at all three stations ranged from
approximately 80,000 to 260,000 cfs with an average of 180,000 cfs
at Kansas City.  Based on the above flows and dissolved oxygen
deficiencies, the oxygen demand was equivalent to the waste BOD
from 80 to 120 million people.  Approximately 3 million population


equivalent is the maximum that can be accounted for from municipal
and industrial sources (16).  Animal wastes are one of the prime
suspects for the large unaccountable pollution load.

Surface water supplies in Kansas have been seriously disrupted by
feedlot runoff pollution.  One such incident is described by an
Official (17) of the Kansas State Department of Health:

       "In 1967 one small Kansas community using surface
       water as a supply source was forced for a period
       of two weeks to treat water with the following
       characteristics:  ammonia content up to 20 mg/1;
       BODg up to 75 mg/1; dissolved oxygen 0.0 mg/1;
       total coliform count 4 million; fecal coliform
       count 2 million, and total fecal streptococcus
       count at 5 million per 100 m/1 sample.  Additionally
       the water was heavily loaded with pungent and
       difficult-to-describe organic materials which
       produced a finished water product highly offensive
       to the senses of taste and smell.  The city was
       forced to use activated carbon and increase
       chlorination by a factor of 10 in order to 'not-too-
       successfully' continue operation of the water
       treatment plant."

There is additional evidence that animal wastes are a major source
of water quality degradation.  During the past year, an  estimated
12 million fish were killed by pollution in our waters.  This terrible
toll reflects only the actual kills discovered and reported.  Many
more thousands of dead fish go unnoticed or unreported each year (18).
Thirty-six fish kills in Kansas streams were investigated by the
Kansas State Department of Health and the Forestry, Fish and Game
Commission during 1967-1968.  Twenty-two of these were attributed
to runoff from commercial feedlots (19).  Spring rains in Kansas in
1967 washed tons of cattle feedlot wastes into the receiving streams
killing an estimated 500,000 fish.  This is not to say that fish
kills are unique to Kansas, but rather suggests a greater awareness
by Kansas officials of the pollution caused by animal wastes.  Recently,
in Kansas, a large dairy herd was decimated after drinking from a well
polluted by the runoff from beef cattle waste.  This dramatically
illustrates the serious contamination that can be caused by uncontrolled
animal wastes (8).

Animal waste pollution is not restricted to the Midwest; it is a
national problem.  In early 1966, the Interstate Commission on the
Potomac River Basin reported (20):

       "Every time it rains ... enormous amounts of animal
       wastes are washed from farmyards into the river,
       rendering it unsafe for swimming .. although only a
       quarter-of-a-million people live in the river basin

          above Great Falls, it has been estimated that the
          number of farmyard animals -- cows, sheep, pigs,
          chickens, turkeys — is the equivalent of a human
          population of 3.5 million.  While most of the human
          population is served by some sort of sewage
          treatment plant, there is no comparable treatment
          for the animal wastes."

Still another affected area is in the great Southwest.  For example,
the residents of Milford, Texas, have brought numerous damage suits
involving pollution against a large feedlot located a mile from the
community (21).  The rapid growth of the cattle feeding industry in
the semi-arid lands of the Southern and High Plains areas has resulted
in the concurrent development of major water pollution problems.

Numbers of cattle on feed and feedlots with a capacity of 1,000 head
or more increased five-fold in the Southern Plains since the mid 1950's (2)
The problem starts with the cumulative build-up of large quantities of
organic waste on cattle feedlots subjected to sporadic and intense
rainfall.  Evaporation rates are high in summer and the limited rain-
fall (15-20 inches annually) comes in sporadic bursts over short time
periods and unless controlled, this runoff will enter the water courses.

One of the most pressing needs in water pollution control is to slow
the eutrophication rate of lakes (aging process) which is accelerated
by overenrichment from agricultural, industrial and municipal wastes.
Lake Erie is the most dramatic -- and potentially tragic — example
of oxygen depletion in the water caused by nuisance aquatic plants
filling the l#ke.  Many other lakes -- large and small — are in the
same desperate condition but have not achieved the national recognition
afforded Lake Erie.  Although other nutrient sources such as municipal
sewage and industrial discharges are big contributors to eutrophication,
the vast amount of manure being produced in this country is one of
the major causes of the killing of a lake or river by accelerated
eutrophication (22).  Nitrates and phosphates cause eutrophication,
and manure contains both of these plant nutrients.  They can be carried
by runoff into the streams or percolate through soils to enter the

In Minnesota, attention to the problem of eutrophication was brought
forth by the study on the Big Stone Lake where preliminary investigations
indicate a large amount of the nutrients entering the lake is from
cattle feedlots.  The Minnesota Pollution Control Agency stated (23)
"there are places in the country where three or four times as much raw
sewage enters our streams from animals as from human beings."  Studies
on Lake Mendota near Madison, Wisconsin, points the accusing finger
at manure carried by spring runoff into the lake as the source of
unwanted nutrient enrichment and growth of water plants.  Limnologists
see eutrophication taking place in other beautiful lakes in Minnesota
and other states (24).


In a statewide survey the University of Missouri analyzed more than
6,000 water samples in Missouri.  Forty-two percent of the water
samples contained more than 5 parts per million as nitrogen nitrate (25).
In some counties in Northwest Missouri, over 50 percent of the wells
sampled contained sufficient nitrogen to be of concern in livestock
production.  Data indicated animal manure to be one of the major
sources of nitrate in water supplies.  There was a definite statistical
relationship between livestock numbers and shallow wells containing

Agriculture's effect on nitrate pollution of ground water was also
investigated in the South Platte River Valley of Colorado.  Most of
the 621,000 cattle in Colorado feedlots (February 1, 1967) were located
in this valley.  Data showed that nitrate under feedlots is moving
through the soil and into the ground water supply.  Since the feedlots
are usually located near the homestead, they may have a pronounced
effect on the water quality from domestic wells.  The findings that
water under feedlots frequently contained ammonium and organic carbon
cause further concern about the effect of feedlots on underground
water supplies (7).


The culmination of comprehensive Federal water pollution control
legislation came with the enactment of the Federal Water Pollution
Control Act, Public Law 660, in 1956.  This law is the basis for the
Federal role and responsibility in water pollution control and stresses
the recognition of the State responsibility in water pollution control.
The amendments represented by the Water Quality Act of 1965 and the
Clean Water Restoration Act of 1966 were extensive and far-reaching.

The official state enforcement agencies are assuming their responsibility
in animal waste control.  For example, eight of the 10 Missouri River
Basin States have enacted or are now in the process of enacting,
feedlot regulations.  Regulations are, in effect, the blueprints
for the animal waste control program.  They act as a guide to planning,
construction and enforcement.  Regulations are needed to ensure the
feedlot operator that the measures he is taking will guarantee a
reasonable tenure of operation.  It is necessary that the operator
know the controls being installed are adequate, and secondly, that
frequent changes will not be sought by the official agency.  Uniformity
which concurrently allows for flexibility must be built into the
regulations.  Different requirements may constitute an economic barrier
and are especially confusing to operators conducting business in two
or more states.

The existing legislation pertaining to feedlot pollution control should
be thoroughly evaluated.  Many of the basic concepts contained in the
regulations are sound.  However, more attention should be directed

to management practices which would prevent the wastes from entering
surface or ground waters.  For instance, the percent removal concept
of municipal sewage treatment is not applicable to the control of
feedlot pollution.  Cattle feedlot runoff is a highly concentrated
organic waste.  The strength may equal that of normal domestic sewage
or may be 10, 100, 1,000 or more times greater.  Feedlot runoff may
still contain, after treatment, as high pollutional parameters as
domestic sewage, before treatment, if percent removal is the only
criterion used for treatment.  Therefore, a "residual" concept of
waste treatment is proposed;  That is, acceptable treatment is that
which reduces the pollution to a prescribed level or residual which
would assure adequate treatment.

Our laws must give due consideration to the location of feedlots.
Feedlots have generally been located without regard to the soil
inventory and associated topographical characteristics.  It may be
not only desirable, but also necessary, to employ zoning regulations
to prevent the encroachment of the animal population into urban
areas, as well as to prevent the encroachment of the human population
into the feedlot areas.  Hawaii and California have shown the way
with the passage of land conservation acts.  Basically, their legislation
prevents encroachment of urban development into agricultural areas
and also provides a more favorable tax assessment for agricultural

Regulations should also provide for a continuing, comprehensive
animal inventory, state by state, drainage basin by drainage basin,
which would provide definitive data on the character and composition
of agricultural effluents, points of discharge and other pertinent
information.  Just as we census the human population, we must also
keep up-to-date inventories of animal populations.

Leadership in animal waste control is not limited to the official
agencies.  Research has been underway in the state agricultural
experiment stations regarding the characterization, handling, and
utilization of animal manures since the turn of the century.  The
U. S. Department of Agriculture and many other Federal and State
agencies are conducting studies related to agricultural pollution.


An enlightened public has shown in all fields of environmental
protection, including water pollution control, that it is willing
to pay, in dollars, the added costs of maintaining a high quality
environment, rather than risk its own destruction.  Enlightened
leadership will continue to create its own consensus.  This paper has
presented an overview of the causes and effects of animal waste
pollution on water quality.  The extent of the problem as well as
the effects on surface and ground waters are illustrated with research
data.  The present status of legislation in regulatory control of
pollution is discussed.  Measures to strengthen present regulations
are proposed.



 1.   Finch,  R.  H. ,  "Finch is Energizer  in the  Administration."   The
     Kansas  City Times,  (May 29,  1969).

 2.   Grub, W.;  Albin,  R.  C.; Wells,  D. M.; and Wheaton,  R.  J.,  "Engineering
     Analyses  of Cattle  Feedlots  to  Reduce Water  Pollution."  Presented
     at the  1968 Winter  Meeting American Society  of Agricultural
     Engineers, Chicago,  Illinois,  (Dec. 1968).

 3.   Miner,  J.  R.;  Lipper, R. I.; Fina,  L. R.; and  Funk, J. W.,
     "Cattle Feedlot Runoff -- Its Nature and  Variation."  JWPCF,  38,
     1582-1591, (1966).

 4.   Gilbertson, W. E.,  "Animal Wastes:  Disposal  or Management."
     Presented at the  National Symposium on  Animal  Waste Management,
     East Lansing,  Michigan, (May,  1966).

 5.   National  Academy  of Sciences, "Water and  Choice in  the Colorado
     Basin."  A Report by the Committee  on Water  of the  National
     Research  Council  Publication 1689,  National  Academy of Sciences,
     Washington, D. C.,  (1968).

 6.   Smith,  G.  E.,  "Nitrate Problems in  Water  as  Related to Soils,
     Plants, and Water."  Water Forum, Special Rpt. No.  55, University
     of Missouri,  Columbia, Missouri, 42-52, (1965).

 7.   Stewart,  B. A., et  al, "Distribution of Nitrates and Other  Water
     Pollutants Under  Fields and  Corrals in  the Middle South  Platte
     Valley  of Colorado." USDA -  ARS Pub. 41-134, Beltsville, Maryland,

 8.   Loehr,  R.  G.,  "An Overview--Wastes  from Confined Animal  Production
     Facilities—The Problem and  Pollution Potential." Presented at
     the Conference on Animal Feedlot Management, University  of  Missouri,
     Columbia,  Missouri,  (Nov. 6, 1968).

 9.   U. S. Department  of Agriculture, "Agriculture  Statistics--1967."
     U. S. Government  Printing Office, Washington,  D. C.

10.   Lipper, R. I., "Design for Feedlot  Waste  Management."  Presented
     at the  Continuing Education  Seminar, Topeka, Kansas, (Jan.  23,  1969).

11.   Owens,  T.  R.,  and Griffin, W. L., "Economics of Water  Pollution
     Control for Cattle  Feedlot Operations." Special Rpt. No. 9,
     International Center for Arid and Semi-Arid  Land Studies,  Texas
     Technological College, Lubbock, Texas,  (Sept.  1968).

12.   Williams,  W.  F.,  Texas Technological College,  Lubbock, Texas,
     Informal  Communiciation, (May 1969).

 13.   Schake, L. M., Texas A6M University, College Station, Texas,
      Written Communication  to FWPCA,  (May 20,  1969).

 14.   Dague, R. R., "Discussion." Cattle Wastes  - Pollution and
      Potential Treatment by Loehr, R. C., and Agnew, R. W.,
      Sanitary Engineering Division, Proc. Paper 5379.

 15.   Mayes, J. L., "The Kansas Animal Waste Control Program."
      Presented at  the Animal Waste Management Conference, Kansas
      City, Missouri,  (Feb.  20, 1969).

 16.   Lightfoot, E., "Waste  Utilization and Conservation." Presented
      at  Joint Seminar between University of Missouri and Missouri
      Pollution Board, Columbia, Missouri, (April 9, 1968).

 17.   Gray, M. W.,  "Regulatory Aspects of Feedlot Waste Management."
      Presented at  the Continuing Education Seminar, Topeka, Kansas,
      (Jan. 23, 1969).

 18.   Moore, J. G., Jr., Remarks before the Western Regional Conference
      of  Trout Unlimited, Denver, Colorado, (Sept. 27, 1968).

 19.   State of Kansas, "Plan of Implementation  for Water Quality
      Control and Pollution  Abatement."  (June 1967).

 20.   Fry, K., "Land Runoff—A Factor  in Potomac Basin Pollution," 1966,
      Interstate Commission  on the Potomac River Basin, Washington, D. C.

 21.   U.  S. Department of Agriculture, "Wastes  in Relation to Agriculture
      and Forestry." U. S. Government  Printing Office, Washington, D. C.,
      (March  1968).

 22.   Smith, G. E., "Pollution Problems—How Much is Agriculture to
      Blame?"  Agricultural  Nitrogen News, (March-April 1968).

 23.   Badalich, J.  P., "Current and Proposed Regulations." Presented
      at  the Symposium on the Disposal of Animal Waste in Agriculture,
      Minneapolis,  Minnesota,  (Nov. 21, 1968).

,24.   Corey,  R. B., et al,  "Excessive Water Fertilization." Rpt. to
      the Water Sub-Committee, Natural Resources Committee of State
      Agencies, State of Wisconsin, Madison,  (Jan. 31, 1967).

 25.   Keller, W. D., and Smith, G. E., "Ground Water Contamination by
      Dissolved Nitrate." Presented at the 164th Meeting of the
      Geological Society of  America.