United States Office of Water EPA 570/9-88-005
Environmental Protection (WH-550) September 1989
Agency
4>EPA Sanitary Survey Training
Field Guide For Sanitarians
Of Micronesia
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FOREWORD
This fieia nindoook ic desired to ierve -35 an onsi'.a aid for sanitarians
ciunnq pucaic heali- field inspections of public drinking water systems.
Ini-, Handbook containc a set of eight inspection-forms which have been
compiled tq facilitate the inspection of a public drinking water system. Each
form has a series of questions designed to guide the inspector in the
consideration of all parameters and factors which may impact the quality and
quantity of the water supply. Spaces are provided to record responses, field
observations, and additional data. Form 1 is to be completed for "all water
-wstems. Forms 2-5 are used depending on the water source... Forms b, 7 and 8
are used for treatment, pumps, and storage/distribution respectively, At the
end of eaen form, there is a detailed explanation of each item and what factors
must be considered in completing each item,
Because this is a handbook, the' information is limited and not intended to
provide a comprehensive coverage of each-item. Sanitarians are encouraged to
use additional references for mere detailed explanations. A list of possible
referuncos is provided at the end of this handbook.
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CREDITS
;Tiu-:; Field Handbook w'js developed by the South Carolina Environmental
ier training grant No. T901536 with the Office of
'.I'raiqing Center (SCETC* ui{
Drinkjin<:\ Water, Chief B r in
Environmental Protection A
i
I
i
The following .individuals
handbook ,.
ing Water Branch, (.'John R. Trax, P.E.) United States
gency.
jere involved in the development of the field
SCJET C... Pr o j e ct. _ D i rector.
Dr. William Engel, Directors South Carolina Environmental Training Center;
Sumtejr Area Technical CoHige, Sumter, South Carolina.
Ken Hay, Kducation/Trainin
3 Specialist; Office of Drinking Water, United States
Eni.n ronnienlal Protection Agency.
A,, Holt in, Fresiden
Willi.au) Sowell. Manager of
South Carolina Department
SCEIC...lProject..Coprdinat(Br.
I" A. Holtan and Associates; Uhiteford, Maryland.
Engineering Surveillance and Technical Assistance;
jf Health and Environmental" Control';" ~ '
SCJSXC...JnstructionaJ....Deyelopient.
Suian HcMaster, Director ojf Staff and Instructional Development; Midlands
Technical College. Coiumbia. South Carolina.
Jann 'Joyroe, Media Special
Carujj ina.
SCETC. ,.Media...Deyel.op|ient.
t'st, Sumter Area Technical Collage; Sumter, South
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ACKNOWLEDGEMENTS
;-;um"r'-»!- texts arid publications have served as sources of information and
resource- .cor the compilation ot this field handbook. The following references
n3v* been used repeatedly throughout the nar.abooK and deserve special
recogniI '.on I
Orinr.inq Water Home Study Program:
uiater TreaUient. Plant. .Q^eraUon.E, Volume 1^
ifia'ter" Ir. Vat went. Plant. dee rations., Volume II
water. y.'-'.p.Q.i.v:. S.vs.t.v-.1!}. 9jP.6JCAt.iJ9J.1
""Ava'iliible from: Kenneth Kerri
Department of Civil Engineering
Calif. State University, Sacramento
6000 J. Street
Sacramento, CA 95810
(Phone; 916-454-6142:'
Water Treatment Plant Desi.gn., prepared jointly b'y the American Water Works
A3SQc\atTori7 Lonference""oF' State Sanitary Engineer i, and American Society of
Civil Enqmesrs
Available from: Data Processing Department, AUWA
6666 W. Quincy Avenue
nenver, CO 80235
Order No. 10006
(Phone: 303-794-7'/ll)
Uater .GuaHt.y. and. Treatment.: A Handj?o.oK. of. Pub.Lic Water. Sujpjp_lies.: American
Uater Works" Association, Third Edition, McGraw-Hill, 1971
Available from: Data Processing Department, AWUA
6666 W. Quincy Avenue
Denver, CO G0235
Order Ho. 10008
(Phone: 303-794-7711)
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TABLE OE CONTENTS
I. SANITARY SURVEY FORMS AND DETAILED FACTORS
1. Public Water System .................. .1-1
2. Springs and Infiltration Galleries ............ 2~1
3. Wells ....... . ............... ... 3-1
4 Surface Sources ..... ................ ^-l
. 5 Catchments. ......... ........... ... 5-1
6 Treatment ... ............. ....... 6-1
7 Pumps ............ ............. 7~1
8 Storage/Distribution
II. APPENDIX A ... ....... -
- "Need to Know1 Math and Calculations
APPENDIX B . . .. ...... -
"Need to Know1 Disinfection
APPENDIX C ..............
List of References ......
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Sanitary Survey
Public Water System Inspection
Date of Inspection
Inspection conducted by
1. ?\.3!ue 01 system
2, ;''«G Hi*
3, Location of system
4,- Owner? address and telephone no..
5. Name of operator _;
6. Per--ion';':-) contacted, address and telephone number ._
Number of people served __.
What is the source? Surface _.
Catchment.
Ground
11. ijces the system provide -an adequate
quanstity of water year around? _____
12, If the answer to #11 is 'no,' what is the limit-
.ino factor? Capacity ______________________________________
Treatment _____________ ..... ______ ..... ________
Distribution _______________________ ....... ....
13. How many master meters does the system
n a v e ?
14. Are the master meters operational?
3.5. How many service connections or stand-
pipes are there?
16. Are service connections metered?
1-1
9, What is the design capacity?
10. What is the present average daily production? __________________ M6D
.?.i No.
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I.'.; Estimate DCrcent of1
PUS Form
Continued
18.; Attach a site plan |:
!
|
19 Attach a treatment C
s e r v ice con n c c t1 o n s
or the system,
hit schematic.
Yes
20.' Doss the operator perform tests for
] Bacteriological) Quality
' Turbidity f
[ Chlorine Residual
i Chemical
i 01 h e r
21.
Is ins water treatment plant operator com-
petent in performing^
Are testing facilitx
adeauste? *
necessary tests?
es and equipment
Do reagents used hasje an expired shelf
i 1.1 e! ,_
34.! Arc records of test :
results maintained?
25. '. How often are the fo
! B 3 ctsr i o1o 3 i caT
; Turbidity
! Chlorine fiesitiu"
! Chemical
".C-irbictity
llowing tests performed?
^Quality
T
^ What are the dates o:f the most recent
I tests ? j;
Bacter iQiogical-j 'Quality
-i
Chlorine
(J n e m i r a J.
; riow oiany times nas ..t|te system failed to
; meet the drinking water standards in the
I p^sx, 12 months? ' ^
| Bactenoloqical^Qual i Ly
Turbidity ^
GiiJorine Kesidu*!
Chemical ' ' 1
No Comments
i -i1
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PUS fcorm
Continued
No COMMENTS
Is the public notified when the'" drinking
water test-:: are not oer formed or when the
tests indicate; contamination'' ^ ___ --- , ---------------
If i:'f'-~, explain; _________ __________ ; __________ _ ....... _____
Describe the problems which need correction'
30, Hollow-up inspection results and date:
Signature a:? person conducting inspection,..
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Name of system - t
DETAILED FACTORS OF FORM
PUBLIC WATER SYSTEM INSPECTION
Enter the name of the water system. Usually, this is the same
name as the! municipality or the qeoqraphical area in which the
system is located,
PWS I.D. -
ublic water_supply (PUS) identification number for the
Enter the
j, - - IT r .1 .-.. . -_ w 11 M j. j. j. t. .j v A WI | | iiJiHU'C J, 1, Ul" Ol
water system. Each PWS is assigned an identification number by
the Kequlatiary Agency.
3,' Location of system/-
Enter the njame of the municipality, township, village or general
Seographical area in which the system it located. Include street
.address, cross roads and any other- directions which would assist
in locating the water system. A person unfamiliar with the system
should be able to locate the system by following this description.
Attach a ma'p if possible*
Owner, addi-ess and
telephone no, -
Record-"the name(s) of the owner is) and the mailing address. This
may be an individual or a municipality, corporation, etc. If the
owner is a~Municipaltty, also record the name of the contact
person.
of operator -
Record the giame of the individual who is in charge of the daily
ooeraiion of the system. .
?ersori(s) contacted;
Record the r
ranie(s) of 3n individuals contacted during the survey.
7. , Number of people served -
Sec or o the
this may be ;
amber oi people serveu by the system. In many cases
an estimate. If it is an estimate, so indicate.
1-
L
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t actors of FWS
Continued
What is the source?
Indicate whether water source is surface. ground or catchment.
More than one type should be checked if the source is from more
than one type. Check each type of source used.
9. What is the design capacity? '
Record tne number of million gallons per day (MGD)
which the system was designed to deliver. For smaller systems you
may record hundreds or thousands of gallons per day. Note: The
desiqn capacity miqht be determined by the amount of source water
available, a specific unit process, the treatment of water or some
limitation in the distribution system. It is important to record
the design limiting factors for future reference.
10. What is the present average daily production?
Record the number of million gallons per day (MGB) which the
system is actually producing each day; This figure may be either
larger- or smaller than the design capacity. For smaller systems
you may record hundreds or thousands of gallons per. day. If
metered records are available you may determine daily production
by averaqing the available information. In the absence of meters
the inspector may have to rely solely on the owners or operators
estimate. This should be so noted.
11. Does the system provide an adequate quantity of water year around?
If customers actually run out of water, then record 'no". Also?
enter additional information under comments regarding informtion
such as how often customers are out of water or times when water
is unavailable.
12. If Answer. -to *11 is *no"n what is the limiting factor?
Indicate the reason why the water system is not providing an-
adequate quantity of water year around. Check either capacity
(i.e. an inadequate supply of water), treatment (i.e. the
treatment process is unable to treat an adequate amount of water
to meet consumer demands) or distribution (i.e. the distribution
system is unable to deliver the volume of water required by the
customers). Also? record under the column for comments
'roecif ic-ally what the limiting factor-;- are; for example, excessive
.i. e .3 k a q e m a y e x p 1 a i r i w h y t h e d i s 1 r i D u t ion s y s t e m is i n c a p a b 1 e o f
delivering an adequate supply of water.
1 .- s
i _'
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detailed F.actors of pus.
13.
How many master meflrs does the system have?
Record the
-lumber of master meters in the system. A master meter
is a large "petered connection either to or from the water system.
This could be the meter is) from which the system puchases water
from another system or from which water is conveyed to consumers
as well as ,]io other systems.
14, Is the master meter
operational?
Record whether the master meter is operating. If there is more
than one meter, indicate which ones are working and which are not.
Under comments also record other pertinent information such as how
ions the met.er has been inoperative and what is being done to
repair the meter.
How many service connections or standpipes are there?
Record how many individual service connections which are served by
the system. A service connection is a an individual tap to a
residence or other consumer. A stand pipe is a single faucet used
16.
17,
; by a n umber -
; Are service connecti
l
; Indicate the
Estimate percent of
i
: Record the n
! connections
whether the '
: (estimated) ;
t h e m .
Mote: To ca"
taps by the -
100, »
1 i
Attach a site plan :£
i *
1 3 site plan
'. such at loca
i access roads]
of consumers,:
ons meter ed?
appropriate response.
service connections metered -
umber or an estimate of the number of service
which are not raetered. Also, be sure to ascertain
meters are working and, if not, how many are
to be inoperative and what is leing done to repair
Iculate percent metered, divide the number of wetered
total number of service connections and multiply by
DT the system -
ts a freehand line drawing indicating key features
lion of water source, security fencing, buildings,
, etc, Be sure to locate the compass direction for
north, "drid"estimate distances between major structures on the site
olan. See t"u ample on Page 1-10.
1-6
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Detailed fcactors on PWS
Continued
19. Attach a treat merit unit schematic
A schematic is a line orawinq which traces the flow of water
throuqh the treatment system. Be sure to indicate points of
chemical addition.,. sampling points, etc. See Example on
Paqe 1-11.
20. Does the operator perform tests for:
Bacteriological Quality
Turbidity
Chlorine Residual
Chemical
Other
Indicate which tests the operator conducts. Be sure to specify
which chemicals are tested for, and record any other type of tests
which the operator may perform. If tests are conducted by an
outside service, record the name and address of the laboratory.
21. Is water treatment plant-operator competent in performing necessary tests?
In order to make this evaluation, you will need to combine both
personal observations and specific questions. A laboratory which
is equipped with outdated chemical reagentsand dirty lab-ware may
automatically raise questions. You may also wish to ask specific
questions about how and where the sample is collected, how the
test is conducted, the sequence of steps and the significance of
the possible results. If still in doubt, you may request that the
operator perform the test for you. Record. iddj.tj.onajl. observat_ions.
yOdei. ?.5J!)MJlis Subsequent questions 22-2-6 will assist in this
determination.
22. Are testing facilities and equipment adequate?
See item 21 for pertinent questions and observations to be made.
23. Do reagents have an expired shelf life?
Every covnmerically prepared cheraical reagent has a date .stamped oh
the container label after which the reliability of the chemical is
suspect. Locally prepared reagents should also be dated and
proper storage is important. Often refrigeration is necessary in
hot climates to ensure the full shelf life.
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Detailed Factors on PWS
C o n t i n u ? d
i
24. Are records of test resc
Its maintained?
Note whether the results of tests are recorded and kept on file at
the water systenj,. A standard form for recording test results will
help organise thjis process.
25.
1
Hoy often are the follow'ins tests performed 1
Bacteriological [Quality
Turbidity
Chlorine Residual
Chemical
Record how many.
performed. Be
performed.
times a day or a week each of these tests are
ure to also record which chemical tests are
What are the dates of tije most recent tests?
Bacteri o1og icai i Qu 31i ty
Turbidity j
Chlorine Residual
Chemical i
The records of the test results should show the date of the most
recent test for "each of the tests above. Be sure to record the
dates for each of the specific chemicals tested for.
27.
How many times has the <
in the past 12 months? ,
Bacter iological-
Turbidity .
Chlorine Residu--
Chemical
ystem failed to meet the drinking water standards
Oua.Lity
1
The record of test results should be compared with the current
drinkinq water standards. The number of times the standards are
exceeded shouldtbe recorded opposite the appropriate test. This
should bo done lor the past twelve months. Be sure to record what
specific chemicals have exceeded the standards.
1-13
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Dec ,:i.iiic t actors or, r'feib
Continued
2S. is the public notified when the drinkinq water tests are not performed or
when the tests indicate 'contamination?
There should be a record or file wincn will provide this
information. Also, determine how the public is notified (by
telephone, newspaper, notice through the mail, etc.) The public
notified should include the Co-burners of the water.
29, Describe the problems which need correction.
Once defeciencies are recorded, prepare a list of specific
, " recommendations (corrections etc) which are necessary. You may
also wish to record a deadline for each of the recommended
actions., ,
30. tallow-dp inspection results and date:
A follow-up inspection should be .scheduled as close to the
established deadline as possible,, The purpose i's to determine if
the recommendations have been acted upon and performed correctly.
1-9
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Example Of A Waterflow Schematic
Raw Water
Pump
rapid
mix
Flocculation Basin
cl
Note: Raw H20 Intake
has 4 possible intake Levels,
2 ft, 5 ft, 7 ft, 11 ft.
1
finished
water pump
Clear well
Chemical Feed
Q/ Potassium Pomanganate
© Lime
(3) Alum
© C12
0 CI2
© Sodium hydroxide
Sample Locations
IAJ
.Gravity
5J Filters
1-11
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1
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Sanitary Survey
and Infiltration Galleries Inspection
Date of Inspection
Inspection conducted by b_.
1, K3M5 of system
2. PwS ID*
3. Location of system
4. Per sonCs) contacted, address and telephone number
5. Type of source: Infiltration Gallery
Spring
6. Capacity 33!Ions per day
7, Number of people served
Yes No Comments
8, is the recharge area protected?
What are the types of protection:
Ordinance
Othsr
10. What is the nature of the recharge area?
Agriculture
Forest
Other (specify.'1 ;
11,. Is site subject^ to flooding?
12. Does the quality of water change
during or after a rain?
13. Does spring or infiltration gallery
have a collection chamber?
14. if yes, is it properly constructed?
2-1
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When was water last
vested:
DliTE
Microbiological
Turbidity
Other (specify)
RESULT
J-
16. ; Was a sample taken dtaring the survey?
i i
17. Analysis of inspection sample:
DftTE RESULT
Microbiological
Turbidity " "I.I
Othor (specify) ']:
18., Describe the problems which need correction
S/ICi Form
Continued
Follow-up inspection
Si3naiu r e of per son conduc
'ate.'
(results and date:
ting inspection
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DETAILED FACTORS OF FORM
SPRINGS AND INFILTRATION GALLERIES INSPECTION
anss- of system
Enter the name of the water system. Usually, this is the same
name as the municipality or the seosraphical area in which the
system is located.
FWD ID* -
Enter the public water supply (PWS) identification number for the
water system. Each PSU is assigned an identification number by
the Mediatory Agency.
3. Location of system -
Enter the name of the municipality, township, village or, general
geographical area in which the system is located. Include street
address, cross roads and any other directions which would assist
in locating the water system. A person unfamiliar with the system
should be able to locate the system by following this description.
Attach a map if possible.
4. Per son(s) contacted -
Record the naise(s) of all individuals contacted during the survey.
5U Type of source
Irifi 1 tration Gallery
Spring '_~_
Record whether the source is an infiltration or a spring. See
Curings and Infiltration Galleries page 2-6 through 2-8.
6. Capacity -
Record the number of gallons per day produced by this system.
7. Number of people served -
Record the number of people served by the system. -In many cases
this may be an estimate. if an estimate, so note»
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D e 1 -311 e d f a e tor s o t S /1B
C o ?! t i n u e d I
\ ' 1
S. Is the recharge areja protected?
i . '[
i The recharge] area is difficult to determine without the aid of a
qualified geologist. For the purposes of this handbook, we will
; .focus on th.su immediate physical surroundings. The recharge area
; is all of th> area which slopes or drains in the immediate vicinty
I toward the spring or infiltration gallery. It is important that
this area be protected from contaminating sources such as
: wastewater, Ispills of hasardous materials, garbage dumps,
; abandoned -automobiles, animal pens, benjos, etc.
10,
If the answer to fSfis yes, what are the types of protection?
There are nujnerous ways to protect the recharge area such as
fencing, ordinances (laws, soning restrictions, etc. preventing
s e p ti c ta n ks j" o r benj o s), e t c«
What is the nature |f the recharge area?
"].
Identify howj the recharge area is being used, such as forest,
agriculturalj residential or- other use. It may also be important
in some cases to record other observations; for example, is the
agr iculturaljuse for crops, cattle or pigs? Obviously, there is
greater concern if pigs are raised in the recharge area.
i !
II... j.3 site subject to flooding?
i i
! d
This is important because floods may introduce contaminates into
the source.
i.2*, Does the quality of!
water change during or after a rain?
If the quality does change,, it means that there is direct flow of
surface ruiVd'ff immediately into the source with little or no
filtration trirough the soil. Other surface contaminants may also
enter the source along with the surface run off.
Joes spring or infiltration gallery have a collection chamber?
A col lect-ran:;
col iactiriCj an
Galleries p3'j
amber is any structure designed for the purpose of
storing water. See Springs and Infiltration
= 2-6 through 2-8,
"> -
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Detailed Factors of S/IG
Continued
14. If yes, is it properly constructed?
A properly constructed chamber is made of a sanitary -and
impervious material such as concrete, steel, ferrocentent, etc,
Provisions must be made for access, sanitary protection and
ventin3. See Springs and Infiltration Galleries, example of
Spring Box page 2-6.
15. When was water last tested?
DATE RESULT
Microbiological
Turbidity
Other (specify)
Record the dates and results for the most'recent tests.
16. Was a sample taken during the survey?
Record both date and type of any samples that were collected
during the survey.
17. Analysis of inspection samples -
DATE RESULT
Microbiological
Turbidity
Other (specify)
Record the laboratory results of all tests conducted on samples
taken.
18. Describe the problems which need correction.
Once deficiencies are recorded, prepare a list of specific
recommendations (corrections, etc.) which are necessary
You may also wish to record a deadline for each of the recommended
actions.
19. Follow-up inspection results and date:
A follow-up inspection should be scheduled as close to the
established deadline as possible. The purpose is to determine if
the recommendations have been acted upon and performed correctly.
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Springs and Seeps
. A spring, or seep]is water that reaches the surface from some underground
supply, appearing as small water holes or wet spots on hillsides or along
river banks. The floiji of water from springs and seeps may come from small
openings in porous ground or from joints or fissures in solid rock.
i
; Before reaching the surface, spring water from a well protected recharge
area is generally frees from harmful contaminants. In order to avoid
contamination, the spijing should be protected at the point where the water
leaves the ground. There are three methods of developing springs as drinking
water sources: spring boxes (see example pages 2-7), horisontal wells (see
examples A S B on page 2-8) and seep development using infiltration gallery
(see examples C X D or page 2-8).
2-6
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SPRING BOX WITH PERVIOUS SITE
Mounded soil
Cover sloped to deflect
rainwater
Diversion ditch 8m above
spring
.^..>..1.:->..^:^ .-v..; 7? /
A High water level. IV /
..: - - i --»..--.._ v.. f -
-.. -. C :.. ___sj
Overflow pipe,
screened
apron
Water
bearing
level
Impervious layer
Outlet (to
storage)
Gravel
2-7
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Example of an
Artesian Spring
HT^/^AV^A galvanized pipe
Example of a
Gravity Flow Spring
Ground Surface
Water table
Open-end
galvanized pipe
Impervous layer
Example of an Infiltration Gallery (Seep Colfection System)
Gravel on uphill side of pipe
Anti-seepage wall
and spring box
Collection
pipe Puddled clay on
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Sanitary Survey
Well Inspection
Date of Inspection ___.
Inspection conducted by
1. Name of system
2. P«JG ID*
3. Name of Well and ID* _.
4. Location of well :
Yes No Comments
5. is recharge area protected?
6,, What are the types of protection;:
Ownership fencing
Ordinances Other
7. What is the nature of recharge area:
Forest Residential
Agriculture,,; . Other
8, Is the site subject to flooding?
9. Is the source? adequate in quantity?
10. Is the source adequate in quality?
11. Does well casing extend at least 12 inches above
the floor or ground?
12. Is weii'properly sealed?
13. Does well vent terminate 18 inches above flood level
with return bend facing downward and screened?
14 r l5oes the well have a suitable sampling tap?
15. Does the well discharge have a backflow
prevention device?
16. Is there a septic tank, benjo or other sewage disposal
facility or conveyance located within 200 feet?
If answer to $14 is yes, ho'w many feet?
is the well protected from animals, etc.?
3-1
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19.
20.
21
24,
What are the types
Fence
Other-
Is there any other
contamination? '
Is there a well log available?
Depth of well
Drawdown
Depth of casing ;_
Depth of grout
of protection?
Building
potential source of
If answer to #21 is yes, what are the sources?
27: Describe the probl
ems which need correction,
-ft
.ft
-ft
ft
Well Form
Continued
Yes
No
28.; Follow-up inspection results and date.
Signature of person CQadycting inspection
Hat'e
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DETAILED FACTORS OF EORH
UELL INSPECTION
Name of system
Enter the name of the water system. Usually, this is the same
name as the municipality or the geographical area in which the
system is located.
PWO ID* -
Enter the public water supply CPUS) identification number for the
water system. Each PSU is assigned an identification number by
the Regulatory Agency.
Name of well and ID* -
Record the official designation assigned to each well. This may
be a name and/or an identification number (ID*).
Location of well-
Enter the name of the municipality, township, village or general
geographical area in which the system is located. Include street
address, cross roads and any other directions which would assisst
in locating the water system. A person unfamiliar with the system
should be able to locate the system by -following this- description,.
Attach a map if possible.
Is recharge area protected ?
The re-charge area is difficult to determine without the aid of a
qualified geologist. For the purposes of this handbook, we will
focus on the immediate physical surroundings. The recharge area
is all of the area which slopes or drains in the immediate vicinity
toward the spring or infiltration gallery. It is important that
this area be protected from contaminating sources such as
wastewater, spills of hazardous materials, garbage dumps,
abandoned automobiles, animal pens, benjos, etc.
If ths answer to *5 is yas, what are the types of protection?
There are numerous ways to protect the recharge area such as
fencing, ordinances (laws, soning restrictions, etc., preventing
septic tanks or banjos) etc.
3-3
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Dot-ruled t-actors on Wells'!
Continued
11,
What i
is the nature of 1 the recharge area?
Identify howVthe recharge area is being used, such as forest,
agricultural-,' residential or other use. It may also be important
in some cases1 to record other observations; for example, is t..a
agricultural :use for crops, cattle or pigs?
i
8. Is ths site subject tc
This is
the sourceu
Is the Eo u r c e a deq u ate
flooding?
important because floods may introduce contaroinantes into
in quantity?
Record whether the consumers are out of water, how often this
occurs, and why*
Ls the source adequat
e in quality?
Refer to labor
meets establ
, D o e s w e 11 c a .: i n q e x te_
atorv results to determine if the water quality
shed microbiological and chemical standards.
at least 12 inches above floor or ground ?
F
Extending thei casing at least 12 inches above the floor or ground
will prevent surface contamination from entering the well and
offer some protection in the event of flooding. See examples of
gravel well construction, page 3-13. The casing may need to
extend higherr^in low lying areas which are subject to flooding.
well properly sealed?
A well cap aiij.the surface mounted pump must be sealed to well
casing to prejent the entry of surface water into the well. This
includes any Openings in the pump base which lead directly into
the well casing such as airlines, gravel tubes, etc.
!, 'I
Joes well vent tsrnuhjrts li' inches above flood level with return bend '
f.a cinq downward and screened?
The vent for the well must be designed to prevent the entry of
surfacs wateijinto the well. See example of gravel well
'". <~, n.-1. / ij o 110 n jf 3 ] e ."' .i.,:.!
3--'
-------
Detailed Factors on Well
Continued
14. Does the well have a suitable sampling tap?
A sampling tap must be located downstream of the check valve and
designed so that surface water cannot enter the well through the
sampling tap. See example of gravel well construction page 3-13.
15. Does the well discharge have a backflow prevention device?
A check valve must be located downstream of the air release-vacuum
breaker valve. See example of gravel well construction page 3-13.
The check valve prevents the flow of water backwards into the
well. No other device other than the air release-vacuum valve is
allowed upstream of the check valve.
16. Is there a septic tank, benjo, or other sewage disposal facility or
conveyance located within 200 feet?
This is especially important when wells are the source of drinking
water. The distance of 200 feet however is not absolute. Other
considerations include whether the waste is uphill from the
sourcein such cases the 200 feet may not be enough. The type of
soil, distance to the ground water table and other factors must be
included in the evaluation.
17. If answer to *14 is yes, how many feet?
Estimate how many feet between the water source and potential
waste sources. See page 3-12 for some recommended minimum
distances.
18. Is the well protected from animals, etc.?
The well should be protected by some structure such as a building,
fence or other conveyance front sources of contamination such as
animal waste, dumping of garbage, et.
19. What are the types of protection?
Record the types of protection (fence, building, etc.) and the
condition of the protection; for example, is the fence falling
down or are there holes in the fence which would allow access?
3-5
-------
Det.
Cont
20.
ileci Factors of Well
inusd
Is there any other
potential source of contami-nation?
Other potential sources of contamination include industrial waste
discharge,lillegal roadside dumping, abandoned cars or nearby
roads on wfjich accidents may introduce oil, gasoline or other
contaminatds into the water source.
If *20 is yes, whati are the sourceslist the potential sources of
contamination. f
Is there a well log available?
A well log Us a record of the thickness and characteristics of the
soil, roek|and water bearing formations encountered during the
drilling of the well.
Deptn of well
The depth of the well should be recorded in the file.
24,
Drawdown
When water "is withdrawn from the well, the level of water
immediately surrounding the wall is lowered creating a cone of
depression. The distance from the static water level to the
bottom of the cone of depression is the drawdown. See Cone of
Depressionjpage 3-14. If the drawdown extends below the depth of
the well, water will cease to flow from the well.
'1
Depth of casing
The casing iof a well is usually a metal or somethimes plastic pipe
which keeps the sides of the well from caving in and closing the
well. The leasing should extend to bedrock where possible.
Depth of grout--
Grout is "a'ljheat cement which is poured into the space between the
sides of trte well rind the casing. After hardening, the grout
prevents surface and subsurface drainage from entering the well.
The depth (if grout should be recorded. See example of gravel well
construction page 3-13.
-------
De t):t 1 ed factar;- of Uej.I
Continued
27. Hesenbe the problems which need correction?
Once defeciencies are recorded, prepare a list of specific
recommendations (correction etc) which are necessary. You may
als6 wish to record a deadline for each of the recommended
actions.
2'd. Follow-up inspection results and date:
A follow-up inspection should be scheduled as close to the
established deadline as possible. The purpose is to determine if
the recommendations have been acted upon and performed correctly.
3-7
-------
the
x
11 u
WELL COMPONENTS
There are various components of a well many of which cannot be observed during
sanitary survey. Sbjie of the more important ones are identified below and
i:;trated on page 3~13'|
Mojtpjr. .]
Air Release'Jacuuriii Breaker Valve:
This valve
system and
prevents air from being pumped into the distribution
eliminates vacuum conditions in the column pipe.
When the well pump is initially started, air inside the pump
column is forced out through the valve to the atmosphere and not
into the system.
when the well pump is shut down, air is allowed to enter the pump
column. This allows the column to dewater into the well.
The valve qi/jst be installed prior to the check valve on the
discharge side of the pump.
T.he opening' in the top of the valve must be equipped with a screen
arid turne'Tldown to prevent entry of rainwater. The valve must be
located above flood level.
c.;
d,!
Valve
Check Valve
A check val]ve is a valve designed to allow flow in only one
direction. 1 A check valve must be installed after the air release
valve on tile pump discharge to prevent the back flow of water from
the systemJback into the well when the well pump is not running.
There shoulfc! be no other devices between the check valve and water
sources. Even though a foot valve (a type of check valve) may be
installed down in the well, another check valve must be installed
and maintained -above grade for easy inspection.
A sample ;p|p is a means for allowing the collection of a water
sample direjctiy from the woll. This sample tap (faucet or
spigot)
-------
Gravel '1'ube
The qravel tube for -adding gravel must be sealed at all times
since this allows direct access to the water in the well.
Gravel Pack
The purpose of the gravel pack is to control the entrance of sand
into the well. The sise (or combination of sises) of gravel is
determined by an analysis of the grain sise of the material in the
water bearing aquifer.
Constructed of continuously poured concrete 18 inches above
finished qrade and steel reinforced.
12 Inch .Minimum
The pump pedestal should extend a minimum of 12 inches below
grade.
3 inch Minimum
The pump pedestal around the well casing should be at least 3
inches thick.
Grout Seal
Grout is a fluid mixture of neat cement (cement and water), saficT
cement (cement, sand, and water) or concrete (cement, gravel, and
water) used to form an impermeable seal between the well casing
and the formation in the drill hole. It is primarily used front
the surface down to an impermeable formation.
The functions of the conductor casing are to maintain the well
hole by preventing the wails from collapsing, to provide a way to
get water to the pumping unit, to form a chamber for the pump, and
to protect the quality of the water. The erasing is generally low
carbon steel, galvanised steel, stainless stell, or in some
smaller installations plastic PUC pipe.
The column pipe is an integral part- of the pump assembly and
serves three purposes: to connect the pump bowls to the pump
head, to convey water under pressure up to the surface, and to
provide alignment for the lineshaft which drives the pump
impellers.
-------
Air line
"t
The air line lis used to measure the level of water inside the
casing. By knowing the exact depth of the air line from the top
of the casing you can determine the exact depth of the water. By
using an air ipump to force water out the bottom of the air line
you can then read the pressure from a gauge attached to the air
line. Remember: For each 1 pound per square inch (psi) you have
a correspond!
X.yJ?J5.
-ig 2.31 feet of water level.
A sounding tube is a piped opening leading inside the inner casing
of the well, j This provides direct access to the water inside the
casing. The sounding tube is generally used for determining the
water level i'n the well by means of a stell measuring tape. This
tube must .be 'securely sealed when not being used.
Screened Vent 1
........._....._...... j, ,
Every well casing should be vented to allow drawdown during
pumping without creating a vacuum on the well casing. Also during
recovery following a pumping cycle the vent allows the water in
the casing to
must be locati
down) so that
s- £yi.P. M.otor. Base. Seal
return the static water level in the well. The vent
?d above flood level, screened and designed (turned
rainwater cannot enter the vent.
The base of tfjie pump motor must be securely attached to the pump
pedestal with!a sanitary water tight seal where the two meet.
t. S.l.ojje
The finished ijrade must be sloped so that surface run off flows
i away from the '.well.
I . !j-
Other points of interest not shown on the example are:
.. are installed fat the intake point of the well to hold back unstable
aquifer material and permit free flow of water into the well. The well
screen should be of go'od quality (corrosion-resistant) metal with mesh
openings which permit
the easy flow of water while screening out sand and
soil particles and has, good structural properties.
yeJJ._head_covers_gr._se3_l_s are used at the top of the casing or pipe sleeve
Connections to prevent! contaminated water or other material from entering
excluding eontaminatiolh are the same.
i r,
-------
Pit'lesT- fdaptero are used to eliminate the need for a well pit. Because of
the flooding and pollution hazards involved, a well pit to house the pumping
equipment or to permit accessibility to the top of the well is not recommended.
These pitless adapters units vary in design but generally include a special
fittinq designed for mounting on the side of the well casing. The well
dis-charge and other piping are screw-threaded into the fitting, providing a
tight seaL.
3-11
-------
i.WJl
.. S .? t w e e n_ 83 _1 1 __ and... 5 o u r c e s_ o f _ Po t _e n t_i a I_ P o .1 .1 u t i o n.
Source!of Pollution
Wells Cased to Depth of
2J_ Lt..!._ :!£.. fit 1 e.L?l._ 9 £_ S!3r..?_
j;eet . Meters
Remarks
Water -tight sewers
Other iiewers
Septic Tanks, Benjos
Sewage!Field, Bed or Fit
Animal:Pens and Yards
50
100
100
200
200
IS
30
30
60
60
Consult the
Agency for
special local
requirements.
3-12
-------
*i T"T~*lj&---'*:""T-:i^~T.^-*^!-*r* s*-»C=
Example of Gravel Well Construction
(Drawing not to scale)
3-13
-------
J-
EXAMPLE OF A CONE OF DEPRESSION
Discharge -*
Screen
-------
Sanitary Survey
Surface Source Inspection
Date of Inspection
Inspection conducted by
1. Name of system
2. !''WS ID *
3, Name of stream or lake
and location
4. Ownership, address and telephone no..
5. What is the nature of the watershed?
Forest
Residential
Agricultural
Other
Yes No Comments
6. Is the watershed protected7
7, What are the typas of protection?
Ownership
Fencing
Ordinances
Other
8. Has a watershed survey been performed?
9. Is the source adequate in quantity?
10. Is the source adequate in quality?
11. When were the recent tests-performed and what
were the results?
Bate Results
Microbiological ,-.,,.-
Turbidity
Total 1'f ihalomathaues , . , __,_
Other , ,,---, ,,-,__,-..
12. Is the raw water intake accessible?
13. Are there any sources of pollution
near the intake?
-------
SS forms
Continued
Yes No
14. Is the intake gravel jpacked?'
1 ' 1
15,. 'How often are the intakes inspected?
| =t -
1&. How often are intakes!" cleaned?
17. What conditions cause
changes in water quality?
Describe!
18. Draw a site plan showing
major potential sourc
1*3. Describe the problems"
Comments
the watershed and relative proximity of
of contamination.
which need correction!
I -"" ~ - - - -
20. ,b'ollow-up inspection results and date
Signature of person conduct inci inspection
I . , . r
-------
DETAILED FACTORS OF FORM
SURFACE SOURCE INSPECTION
Name oi system -
Enter- the name of the water system. Usually, -this is the sanie
name as the municipality or the geographical area in which the
y s t e ni i s 1 o c a t e c .
PWS l.D
the public water supply (P^) identification -number for the
water system. Each PteS is 'assigned an identification number by
the Kequlatory Agency,
flatus of stream or lake
and location
Record the official name of the stream or lake which serves as the
source. Also record the location of the source; use road names.
street addresses, intersections or any combination of landmarks'to
' qeoqraphicaily locate the source. A person unfamiliar with the
system should be able to locate the course by following this
description. Attach a map if passible.
0 g n e r., J d d r e s s a n d t e 1 e p h c n s n o ,
Record the name of the owner/aqency, address and telephone number.
yhai is the nature of the watershed?
The watershed is difficult to determine exactly without a
qeoioqist. For the purposes of this handbook, the watershed is
all of the qround sloping toward the water source. Controlling
the quality of the water entering the source is as important as
the consistency and effectiveness of any treatment process. In
qenerai, a forest area is safer than an agricultural area which is
safer than a residential area. Industrial areas, landfills, etc
are undesirable land uses in a watershed area.
I s the w a t e r s he d pro te c t ed?
Protection of the watershed is important as described in item 5,
Protecting the watershed may be accomplished through ownership or
ordinances which "control land use and fay fences or other physical
barriers which control access to the area..
4-3
-------
Detailed Factors of 55
Continued
; 'i
7. What are the types! of protection?
j
Indicate -the types of protection and combination of methods used
to protecjt the watershed. Be sure to determine who owns the
watershedj 3S this is an imP°rtari't consideration. Record the owner
(name, address and telephone number) of the source if different
than owner of system (Item 4).
i I'
8. Has a watershed survey been performed?
' Review the office files and talk to the owner to determine if and
when 3 watershed survey was conducted. Obtain a copy of the
survey results and use this to assist you in identifying problems
and arear] which deserve additional attention.
'. )
9. Is the source adequate in quantity?
Ask the oij'ner and operator and users of the system how often they
are out of water. Record the number of times and length of time
out of wa1jer. Look for trends as well as frequency patterns in
order to niake recommendations such as additional storage, leak
' repairs, e,tc. to make water available as needed.
10. Is the source adequate in quality?
Check the records to see if the water quality meets the various
standards. Consumer compliants and monitoring results conducted
by the regulatory agency can also provide information.
11.
When were the most Decent tests performed and what were the results -
j
Record the}dates and results for the most recent tests listed.
Compare thpse results with established standards to determine
violations]of water quality. Determine that these results have
been conducted using standard procedures and use these results to
determine changes or corrections in the system.
12.; Is the raw water intake accessible?
! f
.. ; Ihe raw watr»r intake is the location where water is taken from the
lake or stream. It is important that this area is accessible so
tn.jt it car be cleaned and protected.
-------
Detailed fcactors of SS
Continued
13. Are there any sources of pollution near the intake?
Determine if there are any sources of pollution near the intake.
Look for discharge pipes, illegal dumps, roadways, animal pens. etc.
14. is the intake gravel packed?
'Ha*, the surface intake been packed with gravel so that smaller
participate materials are filtered out? Check to see that the gravel
pack is in place and functioning properly.
15. How often are the 'intakes inspected?
The owner or operator should visually inspect the intake structure
looking for sources of pollution, floating debris or blockage. This
inspection should be done routinely and frequently. Record how often
inspections of the intake are performed.
16. How often are intakes cleaned?-
The intake should be cleaned as often as is necessary to prevent
clogging or -he entry of floating debris into the water system.
Record how often the intake is cleaned.
17,. U'nat conditions cause changes in water quality?
Describe the types of conditions such as heavy rains, high winds,
droughts, etc. which cause changes in water quality.
18. Draw a site plan showing the watershed and relative proximity of major
potential sources of contamination..
A site plan is a free hand line drawing showing the watershed and
relative proximity of potential sources of pollution. See example
on page 4-7. The recommended minimum distances between the water
source and potential sources of pollution are listed on page 4-8.
A* stated earlier other factors such as topography, soil types,
distance to water table, etc", must -also be taker, into consideration.
19 describe the.problems which need correction.
Once defeciencies are recorded, prepare a list of specific
recommendations (corrections etc) which are necessary. You may also
wish to record a deadline for each of the recommended actions. .
4-5
-------
I
Detailed factors of SS'
C o n t i i u e d
20. l-'ollow-up inspection r
;esults and date:
A follow-up inspection should be scheduled as close to the
established deadline as possible. The purpose is to determine if
the recommendations have been acted upon and performed correctly.
v
11
-------
"Example of a
Typical Site Plan"
Treatment
Plant
4-7
-------
Source of Pollution
j_WeJJL.3D.1_Source. s_of _P_gt en t i a.l _P0.1.1 ut_ion.
Wells Cased to Depth of
20 ft. (S Meters) or more
Feet
Meters
Remarks
U-'itor-tight" sewers ~ '.'f
Other Sewers .. ' ..
Septic fanKsy Bsh,io'%''" '"'
Sewacie field,. Bed or Pit
flrumai Pens and Yards '
100
100
200
200
Jti
30
30
60
60
Consult the
Regulatory
Agency for
special local
requirements.
4-8
-------
Sanitary Survey
Catchments and Cisterns Inspection
Date of Inspection
Inspection conducted by
1. ' Public water system? Yes No _
2. PWS ID#
3. Name of Household or community
Address
Telphone number
4. Person(s) contacted
5. Number of persons using catchment
6. Size of catchment
Length Diameter
Width or Depth
Depth ^
Calculated Volume
7. Roof or catchment area material and condition:
Material Condition
Galvanized Metal
Asbestos shingle
Concrete
Wood
Other (specify)
8. Storage Tank (cistern) material and condition:
Material Condition
Wood
Concrete .
Ferrocement
Fiberglass
Steel
Other (specify)
5-1
-------
9.
10.
11.
12.
14.
CC Form
Continued
What kind of paint o|r coating has been used on the inside of the
storage tank or cistrern?
Type
Paint
Coating
None
Condition
What kind of paint ojr coating has been used on the roof catchment surface?
Type Condition
i p
; Paint , J
Coating J ~~~
None i ~~~~~
Is the roof catchment system provided with:
Roof flushed ___^
Filter ;j
Other (specify)
None ;]
:j
Is the collection system properly screened to prevent
entry of birds, animals, etc.?
Yes No Comments
.. .j
13. What chemicals are used to treat the catchment water?
Chemical
Dosage
Not Treated
Is the storage tank (cistern)
structually sound ? 1
Yes
No
Comments
15. Is the storage tank (Cistern)
drained and cleaned Regularly?
1 'i
16. Is the faucet for the] storage tank
; (cistern) protected f|rom animals?
17. Is water from the storage tank
(cistern) piped to the house?
5-2
-------
CC Form
Continued
Yes No Comments
18. If piped, is the pipe or hose
connected to a community water
system?
19. When was the water last tested and what were the results?
Date Results
Microbiological
Turbidity
Other (specify)
20. What other purpose is the water used for besides drinking?
21. Describe the problems which need correction.
22. Follow-up inspection results and date:
Signature of person conducting inspection
Date '
5-3
-------
]. DETAILED FACTORS OF FORM
CATCHMENTS AND CISTERNS INSPECTION
1. Public water system f
i
! 1
Record whether this catchment is a public water system or private.
PWS ID# -
Enter the public water supply (PWS) identification number for the
water system. Each PWS is assigned an identification number by
the Regulatory Agency.
3. Name of household or community -
Record the ij.ame, address and telephone number of the household or
community contact person responsible for the catchment.
4. Person(s) contacted'
Record the
catchment.
rame(s) of the individual(s) contacted regarding the
5. Number of persons using catchment -
Estimate the number of individuals who regularly use the
catchment, j,
6. Size of catchment
Measure and record the dimensions of the catchment. See the
sample calculation on page 5-9 and Appendix A-I to assist in
calculating volume
Length
Width
Depth
Volume
or
Diameter
Depth
Calculated Volume
5-4
-------
Detailed Factors of CC
Continued
7. Roof or Catchment Area Material and Condition:
Material Condition
Galvanized Metal
Asbestos Shingle
Concrete
Wood
Other (specify)
Record the type of material used on the roof or catchment area, and
comment on the condition of the material (e.g. rusted, crumbling, rotting,
leaking, etc.) Deterioration of the catchment surface can cause
structural damage and unsafe conditions as well as allow undesirable
materials such as rust to enter the water supply.
Storage Tank (cistern) Material and Condition
Material Condition
Wood
Concrete
Ferrocement
Fiberglass '
Steel
Other
Record the type of material of which the storage tank is constructed, and
comment on the condition of the material (e.g. rusted, crumbling, rotting,
leaking, etc.) Tanks which are deteriorating present problems
structurally which may result in the loss of water and create safety
problems. Deterioration of the inside of the tank can cause water quality
problems by allowing the construction material to enter the water as well
as providing areas where debris, organic material and biological growths
can accumulate. Interior surfaces should be smooth and cleaned and
disinfected periodically.
5-5
-------
Detailed Factors of CC
Continued '
9.
10.
Vihat kind of paint br coating has been used on the inside of the storage
tank or cistern? j.
Type Condition
Paint , 5_ _ _ _
Coating -\ _ __^ _
None a _
. _^_ ^_^_^_^^_^_
Record the type of paint or coating and comment on the condition of the
paint or coating, i,e. blistering, peeling etc. Caution: Lead-based
paint is not acceptable for either the interior of the catchment tank or
the catchment roof surface.
Other materials to avoid include petroleum
based coatings such as tar. The surface of the interior of the catchment
tank should be smooth and cleaned periodically to remove accummulations of
debris, organic material and biological growths such as algae. Disinfection
with bleach or a mild chlorine solution peiodically is also recommended.
What kind of paint or coating has been used on the roof catchment surface?
I
i Type Condition
Paint J
Coatingj ~
None I
Refer to item 9 abo\j'e for conditions and examples.
11. Is the roof catchment system provided with:
Roof flusher
Filter "j
Other (specify)
None
In the absence of rain, an accumulation of debris, bird droppings, etc
will build up on the roof catchment surface. Some system should be in
place to either waste the first runoff (first flush) or filter out the
debris. See examples on page 5-12. Also determine if the flushing system
is operational and l^ow of ten the filter is cleaned or changed.
12.
Is the collection sy|stem properly screened to prevent the entry of birds,
animals, etc? j
Yes No Comments
Just as it is important to exclude foreign material such as bird droppings
from entering the drinking water, it is also important to prevent animals
from entering. f
5-6
-------
Detailed Factors of CC
Continued
13. What chemicals are used to treat the catchment water?
Chemical Dosage
Not treated
Although chemical treatment of catchment water is not typical, some
households may add certain chemicals such as bleach to control biological
growth such as algae in the catchment tank (cistern). It is important to
know not only what kind of chemical ( e.g. cholerine bleach, hypochlorite
solution, etc.) but also what concentraion (dosage). Pages 5-13
through 5-16 provide sample dosage calculations.
14. Is the storage tank (cistern) structually sound?
Inspect for signs of erosion around the base or supporting foundation of
the storage tank. Also look for cracks or deterioration in the tank or
the supporting foundation. Deterioration of the tank can result not only
in the loss of water and accumulation of undesirable organic debris and
biological growths but may also create safety problems.
15. Is the storage tank (cistern) drained and cleaned periodically?
In order to maintain acceptable water quality, it is necessary to drain
and clean the storage tank periodically to remove accumulations or organic
debris which may foster biological growths such as algae as well as impart
undesirable taste and odor to the water. Disinfection with bleach and
mild chlorine solution after cleaning is also recommended. See page 5-14
for a sample calculations.
16. Is the faucet for the storage tank (cistern) protected from animals?
Determine if the faucet (spigot) is accessible to animals such as dogs,
livestock, etc. which may lick or come into direct contact with the
faucet. Correct with fencing or raising the faucet to eliminate
accessibility.
17. Is water from the storage tank (cistern) piped to the house?
Determine if the water is piped to the house.
5-7
-------
I
Detailed Factors of CC {
Continued j
i . "i
18. If piped, is the pipe;or hose connected to a community water system?
Determine if the catchment system is physically connected to a community
water system. If there are connections, this is a cross connection and an
acceptable backflow device (a special one-way acting valve) must be in
place to prevent the flow from the catchment from entering the community
water system during periods of low pressure.
i
19. When was the water last tested and what were the results?
Date Results
: Microbiological
Turbidity!
Other(specify)
Record the results of; -the last tests and determine if they were analyzed
using approved methodology and if they meet approved water quality
standards. Unacceptable water quality may present a danger to the health
of the consumers. This is especially critical if the system is
interconnected with a! community water system.
20. What other purpose is|the water used for besides drinking?
Record the other ways in which the catchment water is used for example:
wash water, watering livestock, etc. .... , . . _. .......
21. Describe the problemsjwhich need correction.
ij
Once defeciencies are! recorded, prepare a list of specific recommendations
(corrections etc) which are necessary. You may also wish to record a
deadline for each of the recommended actions.
22. Follow-up inspection results and date:
A follow-up inspection should be scheduled as close to the established
deadline as possible.
The purpose is to determine if the recommendations
have been acted upon and performed correctly.
5-8
-------
SAMPLE CALCULATION TO DETERMINE
VOLUME OF WATER AVAILABLE FROM A ROOF CATCHMENT
To calculate the amount of water available from the catchment area
follow these steps: (Note: Dimensions used are the roof catchment area size
on page 5-10 with an assumed rainfall of 100 inches per year or 8.3 feet per
year.)
2
1. Determine square feet (ft ) of catchment area
10 ft x 26 ft x 2 = 520 sq ft NOTE: The area of one side of
the roof is multiplied by
2 to include both sides.
2. Convert square ft to cubic ft by multiplying by 8.3,ft rainfall per year.
520 Sq. ft x 8.3 ft/year = 4316 cubic ft/year
3. Multiply cu. ft x 7.48 gal/cu. ft to get gallons/year
431.6 cu. ft x 7.48 gal = 32,284 gal/year
1 cu. ft
4. Multiply this total by 80 percent. Not all water will be available
because of losses due to evaporation and run-off that does not flow into
the gutters. To be safe, figure a 20 percent loss for a rain catchment
area.
32,284 gal x 80 = 32,284 x .8 = 25,827 gal/year
year 100 1 .
5. Divide total gallons by 12 to get average gallons per month.
25,827 gal/year = 2152 gal/month
12 mo/year
6. Divide again by 30 day/month to get average gallons per day.
2152 gal/month = 71.7 gal/day
30 day/month
5-9
-------
Straps I
Cistern inlet
Example of a Roof Catchment Area
Not to Scale
c
T
u
-------
FILTER AND FOUL FLUSH DEVICES
Dust, leaves, and bird droppings will accumulate on the roof during periods
of no rain. These materials are washed off with the first rain and will enter
the cistern and contaminate the water unless a filter or a foul flush device is
used.
Several techniques are available for diverting the first roof run-off from
the storage tank. Water from the gutters runs through the downpipe and into a
small box built on top of the cistern. The first run-off is caught by this box.
The examples on page 5-12 illustrate two methods of allowing only clean water to
enter the cistern.
5-11
-------
Example of a Foul Flush Box
Screened
intake
Downpipe
Removable cover
\ Screen
Cistern
Fig. 1.4 Foul Flush Box
Overflow pipe
Tap to drain out flush
Example of a Filter System
Cistern
A
Fine screen
Gravel
Sand
Charcoal
Pea gravel
Downpipe
Coarse screen
removable
\
Overflow
Fine cover or
plastic screen
Fig. I.5. Filter System
5-12
-------
DOSAGE CALCULATIONS
The following concentraion equivalents and formulas are provided along with
examples to illustrate how to calculate dosages.
A. Concentration Equivalents
Concentration Percentages
1,000,000 mg/1 100%
100,000 mg/i 10%
10,000 mg/1 1%
1,000 mg/1 0.1%
100 mg/1 0.01%
10 mg/1 . 0.001%
1 mg/1 0.0001%
B. Formulas
1. Loading
Pounds = MGD x 8.34 Ibs x mg/1
Day gal.
2. Gallons (GPM) = Gallons x 1 day x 1 hr.
Min. Day 24 hr. 60 min.
1440
3. milliliters (ml/min) = gallons x 3.78 1 x 1000 ml
min. min. gal. 1
4. Chemical Volumes
xV,
where C. = concentraion of chemical that is provided
( i.e., 5% bleach or 65% HTH)
V = volume of chemical
(dosage needed)
V_ = size of tank (gallons)
C? = final concentration that is required
This is sometimes referred to as a dilution equation.
5-13
-------
Dosage Calculations ;]
Continued i
i ' J
Normally a more concentrated solution is added to water to make a dilute
solution. i:
Examples I and II relate to using liquid bleach.
i
Example I J
A storage tank has arvolume of 3000 gallons. How many gallons of and how
many liters of cholorine bleach (5%) would be needed to disinfect the tank in
order to provide a dosage ;of 5 mg/1?
cl x vl
= C0 X |v
x liters
°' i
= 5_mg/l ', x 3000 gal
50,,000 mg/1
= .30 gallons of 5% bleach
j
= .30 gallons x 3.78 1
gal-
I
= 1.13 liters
5-14
-------
Dosage Calculations
Continued
Example II
A water storage tank has the following dimensions:
diameter 8 feet; height 6 feet.
How many gallons and how many liters of chlorine bleach (5%) would be
needed to disinfect this tank in order to provide a dosage of 5 mg/L?
cl = 5% or 50,000 mg/L c2 = 5 mg/L
v = x V2 = 2254 £allons
v2 = TTxRxRxH
= 3.14 (4 ft)(4 ft)(6ft)
= 3.14 (16 cu. ft.) (6 ft.)
= 301.4 cu. ft
Gallons = 301.4 cu. ft x 7.48 gal
cu. ft
= 2254 gallons.
2
v = c x v
Cl
= 5 mg/1 x 2254 gallons
50,000 mg/L
= 0.23 gal of 5 % bleach
To convert to liters
liters = gallons x 3.78 L/gals.
= 0.23 gal x 3.78 L/gals
= 0.85 liters or 850 ml.
5-15
-------
Dosage Calculations j
Continued -f
Examples III and IV relatejto using solid HTH (65%)
Exampl^ III :;
A storage tank has a volume of 6000 gallons. How many pounds of HTH (65%)
would be needed to disinfect"] the tank in order to provide a dosage of 200 mg/L?
Ibs = MG x 8.34 x rag/1
\ = 6000 x 8.34' xl 200
= 10 Ibs
Since HTH is 65%
then 10 Ibs =
.65
15.:
bs
Example IV
A water facility has a flow rate of 500,000 gpd. The cholorine residual in
the distribution system needs to be maintained at a concentration of 1 mg/L.
a. How many Ibs/day 6.5J2 HTH are required to maintain the 1 mg/L residual?
b. If the facility uses a 55 gallon storage facility (day tank), what is
the feed rate in ml/minutes to the system?
a. Ibs/day = flow x j 8.34 Ib/gal x mg/L
(MGD) I
.514 MGD
x 8.34 x 1
= 4.17 Ibs/day
using 65% HTH then 4.17 = 6.41 Ibs/day
" <.65
b. GPM = 55 gallons ] = 1 day
day
1440 minutes
ML/MIN = .038 gallons x 3.78 L x
min. | gal
'!'.
= 144
1000 ml
5-16
-------
Sanitary Survey
Treatment Inspection
Date of Inspection
Inspection Conducted by
I . N a m e o 1' s y s t e m
Name of treatment plant
winat typesis) of treatment are used7
" Pretreatment chemical Addition filtration
Chlorination Hone
Attach a treatment unit schematic.
i. What chemicals are used, why and how much is used in pounds per day;
Name fur pose Liosage (Ibs/dy)
Yes No
7. .Is chemical storage safeT ______
8. Is mixing of chemicals adequate?
9 u is equipment in sood repair?
10. Is equipment operated properly?
1 1 u Is procecc adequate based on visual observation?
12. is equipment in good repair?
13. Is equipment operated properly?
Ei.j:trajt_i_opri
14. What type of filter is used? _______________ .......
15,, is process adequate based on visual observation and
w a t eT q u a i i ty t e st ing?
16,, Are instruments and controls for filtration process
adea.uste,, operational and being used?
6-1
-------
C h 1 o r i n a t i o n
T"' "
17. Where is chlorine applied? Pre Post
18.
19.
Does the operator keej) a log/record?
Type of chlorine usedj Gas
; ; t Liquid
Dry
I
Is adequate chlorine;
properly'
residual beinq maintained?
Is equipment being operated and maintained
Is there sufficient contact time between the
ch 1 or i nation point an]>:i first point of use?
!:; operational standb
y e q u i p m e n t a v a i,; a D i e Y
H r e s p a r e p a r t s read i" 1 y a v a liable?
How m u c h c h e in i c a 1 is'
jsed? Ibs/day
2t>. | Is chl or i nation room Vented to the outdoors?
A r e . f e e d 1 i n e s o p e r a tji n 9 p r o perl y ?
Have there been interruptions in chlorination
d u r i n -. j the past yea rJP;;
29.
If so, why?
Treatment Form
Continued
Yes
.30. Describe the problemsjwhich need correction.
;i. 'Fol.iow-up inspection i-esuita and date
-e
S .1 '- ."i a |t u r e o :(' p e r ;; o n c o r\ d (.i c tf.i n }
//3 'in _ ............... ___ ..... '_ ......... j
i r , s p e c t i o n
-------
DETAILED FACTORS OF EORH
TSEATMEivT INSPECTION
Name oi" system -
Ent.Pr t.he name of the water system. Usually this is the same name
as the municipality or the qeopqraphical area in which the system
is located.
pys I.D. -
Enter the public water supply (PUS) identification number for the
water system. Each PUS is assigned an identification number by
the Regulatory Agency.
Name of .treatment plant -
Record the name of the treatment plant if different from the name
of the system,,
Tyoe(c) of treatment used?
Pretroatment
Chemical Addition
filtration
C n 1 o r i n a t i o n
Hone
Record the type
-------
Detailed Factors of Treatment
Continued
7. Is chemical storage! safe?
Determine ijf the storage areas and storage methods are safe.
Chemical stjorage should be elevated off the floor and only
compatible phemicals should be stored together. Incompatible
chemicals sXich as grease and oils should never be stored next to
oxidisers such as granular chlorine (HTH). Storage areas should
be dry, clejan, cool and direct sunlight excluded.
jjj.xji.jn3 ;|
8. Is mixing of chemicals adequate?
Check where; chemicals are added to see if there is sufficient
turbulence or stirring to ensure thorough mixing. Also, check to
see if the points of chemical addition are sufficiently separated
to prevent unwanted interaction between chemicals.
9. Is equipment in goocl repair?
Inspect the,equipment used for chemical addition. Do motors run
hot, make excessive noise, have excessive vibration or leak oil?
Have calibration checks been performed to ensure accurate feed
rate? Are spare parts and back-up equipment kept in stock.
10. Is equipment operated properly?
Inspect equipment to determine if it is used properly. Is the
equipment used for the purpose for which it was designed? Many of
the observations listed in item 9 above may signal operational
problems. Look at the files on maintenance to determine if
routine maintenance and servicing is performed.
LL°..9.£.M.Lt.'t.ip' n/Sedimentatioiii
11. Is process adequate based on visual obervation?
Inspect the
sample from
flocculation and sedimentation areas. Draw or dip a
the flocculation tank and observe the floe. (The
= .. in P j. = 1.1 urn A.IIC j. iui.-i.-uJ.-31.-J.UM (,-diir-. .ana oc'serve tne iioc. tine
small but visible whitish cloud-like particles which form in the
water when the flocculation chemicals are added is called floe.)
Floe that is] too light and fluffy will not settle. Eloc that is
too small 'pan floe1 tends to settle too quickly without removing
the undesirable material. Check to see if the floe settles out
too soon or Carries over beyond the sedimentation area.
6-4
-------
tTictors of 'Ire-stroent
Continued
12. is equipment ^n good repair7
ppr tn itpm y for potential problem signs and consider the ^
following: Does i'iocculator drive work? Is operation smooth;
ftp* all Boards and/or paddles present? Are there any oil or
qrease leaks. If variable speed fiocculator drives are used, do
thev operate properly at all .peed.? Are all belts and sprockets
in good condition7 Are spare parts available?
Is equipment operated properly?
Refer to item 10 for potential problem signs.
I j. I tr.:il_ioij .
14. What type of filter is usea?
thp number and type of filters, and the components of the
media. Include information such as filtration rate, flow
rate control, and how often the filter media has been changed or
replaced. See types of filters page 6-14/15.
15. Is process adequate based on visual observations and water quality testing-
Look at the water leaving the filter, if it is turbid or colored,
there «av be problems with the filter. Is effluent turbidity
consistently less than 1.0 MTU? (turbidity units)
16,, Are instruments and controls for filtration process adequate, operational,.
and being used?
Inspect the instruments and controls for the filtration process.
Turbidimeters should be operational and controls should be
operating prcperlv and filter loss of head should be calibrated
and tracking properly. See troubleshooting tips for filtration
process page 6-16/18.
17. Where is chlorine applied?
Determine if chlorine is applied at the beginning of the treatment
process (pre), or at the end of the treatment process (post). If
not normally fed at one of' these locations, but the capability is
present so note.
6-5
-------
Detailed Factors of Treatnifnt
Continued I
18. tioes the operator- keep a log/record?
: i
Determine if tine operator keeps a 103 or- record of the day to day
operations of jthe treatment system. Look for information on
chemical dosages, water quality (raw and treated) and equipment
maintenance, [-
' !i'
: ... , , :
I9/ '.type of chlorine used.]
- -I-
Gas j
Liquid 1
Dry """"""" f
. J ^ ij1
Record the typ'je(s) of chlorine used. Gas chlorine is stored in
cylinders (ISO lb or 1 ton). Liquid chlorine is stored as a dry
powder (calcium hypocholrite; and mixed with water for addition in
the system, Bjleach (sodium hypochlorite) may be used in place of
calcium hypochjlorite. See Appendix B for additional information
on cholerine disinfection.
1 ... j
20, is adequate chlorine residual being maintained?
,1
Conduct chloripe residual tests, and review operating records to
determine if adequate residual is being maintained.
EapresentativeTand remote sections of the distribution system
should also b:ej tested in addition to the various unit processes at
i, h e t r e a t m e n t f, a c i 1 i t y.
' ; f "
21. Is equipment being opeiated and maintained properly?
See item 10 atuave. Other consideration include corrosion,
.accumulation of, sediments, leaks, calibration, etc.
i . -(
j
Is there sufficient corjtact time between the chlorination point and first
point of use? j
: . j
Groundwater systems with good raw water quality normally require
30 minutes contact time. Surface water systems will require at
least two hours.
23. Is operational standby jequipmenl available?
Determine if thjere are operational back-up pumps and other
chi-orination equipment available. Also, determine how long it
would take to Have t.he replacement available for installation.
ts-b
-------
Detailed taccors of Treatment
Continued
24. Are saare parts readily available?
Determine if there arc soare parts available. " How long would it
take for the parts to be available for use? Are the parts the
correct replacements?
25. How much chemical is used? ibs/day
Determine what chemical(s) is used and how many pounds are used
each day.
26. Is chlorination room vented to the outdoors?
When usinq chlorine gas, it is important to determine if the air
inside the chlorination room can be exhausted to the outside.
Forced air is preferred, and the vent should be at floor level.
27,, Are feed lines operating properly?
Determine if the lines through which the chlorine is fed are clear
and in good condition. This is important for both gaseous and
'liquid chlorine. Look for crimped or corroded lines as well as-
other blockage. Check to see if anything is coming out of the
feed line either visually or by testing the water being treated
with cholerine.
28, Have there been interruptions in chlorination during the past year?
Determine if there have been times when chlorine was not being
fed. How often and for how long?
29. If so, why?
Determine why there have been interruptions in the chlorine feed
and how they can be controllec. Possible causes may include; out
of chlorine, power failures, equipment failure,- etc.
30. Describe the problems which need correction.
Once defeciencies are recorded, prepare a list of specific
recommendations (corrections etc; which are necessary. You may
also wish to record a deadline for each of the recommended
actions,,
6-7
-------
Derailed Factors of Treatment
Continued |
-i1
31,. follow-up inspectidjfi results and date,
A follow-up inspection should be scheduled as close to the
established deadline as possible. The purose is to determine if
the recommendations have been acted upon and performed correctly,
-------
Example Of A Treatment Unit Schematic
Depth
max.-12 ft.
avg.-5 ft.
/ Raw Water
\ PU^P
\ >^\, 'P 'p sf
r
Intake
ssible intake Levels,
., 7 ft., 11 ft.
El
rapid
mix
Settling Basin
finished
water pump
^
/? /
Flocculation Basin
E ©
BH
\
y^v Gravity
^ W Filters
Clear well
Chemical Feed
vl/ Potassium Pomanganate
(D Lime
© Alum
© CI2
© CI2
© Sodium hydroxide
Sample Locations
a
m
6-9
-------
EXAMPLE OF CHEMICAL TREATMENT CALCULATIONS
!
I
.!
' - : T
It is often necessary to calculate specific dosages (i.e. the amount of a
chemical per volume of water) necessary to ensure that the proper concentra-
tion of a chemical is available in the water to accomplish its intended
purpose. Calculations will also ensure that there is not too much of the
chemical in the water which may cause adverse public health risks as well as
increase the cost of treating the water. The following sample calculations are
presented to assist in making typical dosage calculations.
'!'
Sample Calculations I
: j:
1. To determine the actual chemical feed rate from an alum feeder, an
operator collects the alum from the feeder in a bucket for three minutes.
The alum in the bucket weighs 0.1 pounds.
; '" ]
'!
Known j Unknown
Weight of alum, Ibs =0.1 Ibs Actual Alum Feed,
Time, min =3 min ' Ibs/day
i
1 !
Calculate the actual alum!feed rate in pounds per day.
.i
Actual Alum !
Feed Rate, = (Alum Wt, jbs)(60 min/hr)(24 hr/day)
Ibs/day Time;Alum Collected, min
= (0.1 Ibs)(60 min/hr)(24 hr/day)
i 3 min
I
= 48 Ibs/day;;
2. A solution chemical feeder is calibrated by measuring the time to feed 500
milliliters (ML) of chemical solution. The test calibration run required
four minutes. The chemical concentration in the solution is 12,000 mg/L
or 1.2%. Determine the chemical feed in pounds per day.
Known I Unknown
Volume Pumped,. mL == 500 mL Chemical Feed, Ibs/day
Time Pumped, min 1= 4 min
Chemical Cone., mg/L f!2,000 mg/L
6-10
-------
Example of Chemical Treatment Calculations
Continued
Estimate the chemical feed rate in pounds per day.
Chemical Feed _ (Chem Cone. mg/L)( Vol Pumped mL)(60 min/hrX24 hr/day)
Ibs/day ~ (4 min)(1000 inl/L)(1000 mg/gm)(454 gra/lb)
= (12,000 mg/l)(500 mL)(60 min/hr)(24 hr/day)
(4 min)(1000 mL/L)(1000 mg/gm)(454 gm/lb)
=4.76 Ibs/day
3. A chlorinator is set to feed twelve pounds of chlorine per day to a flow
of 300 gallons per minute (0.432 million gallons per day). What is the
chlorine dose in milligrams per liter (mg/L)?
Known Unknown
Chlorinator Feed, Chlorine Dose, mg/L
Ibs/day = 12 Ibs/day
Flow, MGD = 0.432 MGD
Determine the chlorine dose in milligrams per liter.
Chlorine Dose, mg/L _ Chlorinator Feed Rate, Ibs/day
(Flow, MGD)(8.34 Ibs/gal)
12 Ibs/day
(0.432 MGDX8.34 Ibs/gal)
=3.3 mg/L
The following Table provides the more commonly needed conversion factors and
equivalents necessary for converting units of weight, concentrations, flow rates,
feed rates, jar test dosages and pressure.
6-11
-------
TABLE OF
CONVERSION FACTORS AND EQUIVALENTS
A. V
POUNDS
1.0
0.0625
0.00014
0.002205
VttlGHT
OUNCES
16.0
1.0
0.0023
0.03527
GRAINS
7,000
437.5
1.0
15.432
GRAMS
453.6
28.35
0.0648
1.0
1.6 pound (Ib)
1.0 ounce (oz.)
1.0 grain (gr.)
1.0 gram (g.)
1 ton (T) j = 2,000 pound (Ib.)
1 kilogram (kg) | = 1,000 grains (g.)
Density of water = 1.00
Density of mercury j = 13.56
1 U.S. gallon (231 cu. in.)|of water weighs
1 English gallon (Imp. gal.j of water weighs
1 cubic foot (cu. ft.) of water at 39.1° C. weighs
1 cubic foot (cu. ft.) of water at 62° F weighs
i b. CONCENTRATION UNITS
1
1
1
1
1
1
1
,5
J ..... J
.0 pound per million gallor
.0 pound per 1,000 gallons
POUNDS
PER PARTS
MILLION PER
GALLONS MILLION
(Ib./mg) (p. p.m.)
,s (Ib./mg) 1.0 0.1198
(lb./l,000 gal.) 1,000 119.8
.0 part per million (p. p.m.1) 8.345
.0 grain per gallon (gr.p.g.) 142.857
1 part per million (p.
p.m.) = 1 milligram per liter
C. FLOW RATE
CUBIC FEET
PER SECOND
(c.f.s.)
cubic foot per second (c.f.s.. cusec..
or cu. ft. /sec.) 1.0
million gallons per day (nigd) 1.54723
gallon per minute (g.p.m.) 0.002228
1.0
17.118
(mg./L.)
MILLION
GALLONS
PER DAY
(mgd)
0.646316
1.0
0.00144
8.345 pounds (Ib.)
10.00 pounds (Ib.)
62.425 pounds (Ib.)
62.375 pounds (Ib.)
GRAINS
PER
GALLON
(gr.p.g.)
0.007
7.0
0.0584
1.0
GALLONS
PER
MINUTE
(g.p.m.)
448.83
694.4
1.0
1 cubic foot per second (c.f,. s)
H-
1 gallon per minute (g.p.m.)]
= 646,316 gallons per day
(g.p.d.)
63.1 milliliters per second
..,. I (mL. /sec.)
million gallons per acre; per day (MGAD)
= 2 gallonis per square foot per minute (gal./sq. ft./min.)
=3.2 inches rise per minute (in./min.)
= 1.0 times filter rate (normal)
1 day = 24 hours = 1.440 minutes = 86,400 seconds
6-12
-------
I^Hlc Ui: LU?''V;:RSI(JN i: AC-TOSS AND fiGlUIVfiLEHTS
i ounce DOT minute (as./nun.)
i pound per minute (1 fa,/rain.)
1 pound per day (ib./da.)
i qrara per minute (g./niiri.)
D. FEED RATE
= '-' 0 p o u n c p e r day (Ib./da-.)
- 1,440 pounds per day Cib./da.)
~ 0.3150 grams per minute (g./ruin. 5
= 3,177 pounds,' per day (Ib./da.)
Volume of Jar
I gallon (gai.)
1 liter
-------
FILTRATION - TYPES OF FILTERS
Gravity FiltrationrCsand, dual media, and mixing media)
In all gravity filtration systems the water level or pressure (head)
abo'v>e the media forces the water through the filter media. The rate at
which water passes-jthrough the granular filter media may vary from 2 to
about 10 GPM/sq ,ft(l.3b to 6.79 liters per ssc/sq m or 1.36 to 6.79
This rate of flow is commonly referred to as filtration rate. However,
many slate health .authorities limit the maximum filtration rate to 2 or 3
GPM/SQ ft (1.36 or '2.04 liters per sec/sq m or 1,36 to 2.04 mm/sec) for
gravity filtration,,;. The rate of water flow through the filter is the
hydraulic loading o,r merely the filtration rate. The filtration rate
depends on the type, of filter media,,
Filter mejdia consists of the following substances:
1. Single meidia (sand),
2. Dual mediia (sand and anthracite coal), .and
3. I'lulti or 'mixed media (sand, anthracite coal, and garnet).
j
j
Activated carbon can also be used along with the above filter media for
:o e m o v 3 1 o f t a s t e s y p d o r s , a n d o r q a n i c subs t a n c e s .
I
r
In gravity .filtration the particulate impurities are removed in/on
the media, thuSe.3ui.ing the filter to clog after a period of filtration
time,, In spite of phis, gravity filtration is very widely used in water
treatment plants. Filters are backwashed periodically to remove the
t r a p p e d p a r t i c u 1 a te! i m p u r i t i e s.
Pressure Filtration](Mixed Media)
A pressure filter is similar to a gravity sand filter except that the
filter is completely enclosed in a pressure vessel such as a steel tank,
ami is operated undar pressure,
Pressure filters freqently offer lower installation and operation
costs in small filtration plants; however, they are generally somewhat
less reliable than gravity filters :atrsen.jing upon pumped pressure).
Diatomaceous Earth Filtration
,,i
r -i
In diat-omaceou"'j' earth (precoat) filtration the filter media is added
to the water being Created as a slurry; it then collects on a septum (a
pipe or conduit with' porous walls-.or ether appropriate screening device.
After the initial pVecoat application, water is filtered by passing it
through the coated screen. The coating thickness may be increased during
the filtration process by gradually adding more mediaa body feed. In
most water treatment applications diatornaceous earth is used for both the
precoat and body-fee?:! operations,
i
Diatoaaceous earth filtration is primarily a straining process, and
:n.nd£ wide application where very high particle removal efficiencies (high
.5.':;.riT-.V_w.=?t..;are .required,, such as in the beverage and food industries.
t) - 1'}
-------
Precoat filters can be operated as gravity, pressure or vacuum filters.
They are also commonly used in swimming pool installations due to their
small si.se, efficiency, ease of operation and relatively low cost. They
find limited use in larger water treatment plants due to hydraulic 'Iflow),
sluaqe disposal, and other operational considerations.
4. Slow Sand Filtration
In slow sand filtration, water is drawn through the filter media
(sand) by gravity as it is in the gravity filtration process. However,
this is generally where the similarity between these two filtration
processes ends.
In the slow sand filtration process, particles are removed by
strainingf adsorption, and biological action. Filtration rates are
extremely low {Q.Q15 to 0,15 GPM/sq ft or 0,01 to 0.1 liters per sec/sq m
or O.OL to 0.1 mm/sec)',,
The majority of the particulars material is removed in the top
several inches of sand, so this entire Layer must be physically removed
when the filter becomes clogged.. This filtration process has found
- limited application due to the large area required and the need to
manually backwash the filters
-------
ISOUBLESHOOTINQ TIPS FOR FILTRATION PROCESS
Water Quality
Turbidity
Color.
Head Loss
Location
infT./em,
infi:./effl,
Sampling
..Fre_quen_cy_ li.£S...f.P.r....C)j)erator.. Action.
Influent at least
once per 8-hr
shift, Effluent
every 2 hour^.
At least once per
8-hr shift.
At least three
times per 8-hr
shift
Filter and
?3.C-kwash Ojter at.ion
Chiri:3
-------
Filter Media
Condition.
hod ITS depth filter At lea;:!, monthly.. i. Replace lost filter media.
evaiuatiori. module
fcedxa , 2. Change backwash procedure.
c: 1 eon 11 nest.
Cracks or 3. Change chemical coagulants.
shrinkage.
Make visual
Observations
of Backwash
Oj.er.at ion
Check for media £..... oer At least once per 1. Change backwash rate.
boils. Module day or whenever
backwashing occurs
Observe media when less 2. Change backwash cycle time.
ex pans 10 riu frequent.
Check for media 3. Adjust surface wash rate or
carryover i!;to cycle time.
washwater trough.
Observe clarity of 4. Inspect filter media and
wastewater. support gravel for
disturbance.
Check Filtration
Process and Back-
wash Equipment
G°D.?!J:.M.OD. _.. :._
Noise Various Once per- 8-hr. i. Correct minor problems.
shift.
Vibration 2. Notify others of major
p r o b 1 e in s.
Leakage
Overheating
S-17
-------
Inspect
Facilities
Check physical
facilities,,
Check for algae
buildup on filter-
side walls and on
w -a s hrw a t e r 11 o u q h s,
Various Once per 8-hr
shift.
1. Report abnormal conditions.
2. Remove debris from filter
media surfaces.
3, Adjust chlorine dosage to
control
6-18
-------
Sanitary Survey
Pump Inspection
Date of inspection _^ ,^. -.
Inspection conducted by ..
1. Name of system .---
2. P'W:.; LD. .; __..
3. Name of treatment plant or name and location of pumping station
4, Location of ?ump(s> .
5. Pump inventory
~ii~riii"~iiriiii~~3.iii_ii.
H. What is purpose of the pump?
_Uue abbreviation Key 1 --
B. what is the pump type?
Use..., 3.bb.rev.i3t.i,gri_Ke^_2., _. .
C. Is information on pump
' operation available?
-------
Pump Form
Continued
Abbreviation Keys for A. Purpose, B. Type, E. Emergency Power
Key 1 (A. P-.
Used for: ;
Raw Water KU
Surface - - !' S
Well ; W
Booster : B
Treated Water L-v
Other (specify!)
Turbine Horisontal
Turbine Vertical
Centrifugal >
Submersible
Other (specify)
TW
TV
C
S
f.P.."Jl.
Diesel Generator
Gasoline Generator
Other (specify)
6.
Is facilty properly protected against
trespassing and vandalism.
7. Describe the problems which need corraction
S. Follow-up inspection results and date
Signature of person conducting inspection
KI'II' i
Date ; ^
DQ
86
YES NO
COMMENT
-------
DETAILED FACTORS OF FORM
PUMP INSPECTION
1. Mams? of system -
Enter the name oi the n-ater. system. Usually this is the same name
as the municipality or the qsagraoniC-*! area in which the system
is i o c a i- e d
Enter the public water suppiy (PUS.' identification number for the
water system. Each PUS is assigned an identification number by
the Kegulatory Agency.
3. Name of treatment plant or name and location pumping station -
Record the name of the treatment plant or the pumping station if
separate from the treatment plant and include a map locating the
pumping station. . .
4 . L o c a 1 3. o n o f p u m p C s ) -
If one pump, write in where it is located within the system. If
more than one pump, attach a schematic of system locating each
pump. A schematic is a line drawing of the water system showing
the location of key components of the system. An example is
provided on page 6-9.
5. Pump inventory
Assign a number to each pump and record the following information
for each pump.
A. What is the purpose of the pump?
Using Key 1 record the purpose for each pump. Note: several
pumps may be used, for the same purpose.
B. What is the pump type?'
Usinq Key 2- record the type of each pump.
C. Is information on pump operation available?
Information on pump operation should be available for
reference and kept in a location which ensures its
availability. This information is important to operating,
m a i n t a i n i n g , a n d r e p a i r i n g t h e p u m p ,
7-3
-------
Detailed fcactors of Pump
Continued
G.
H.
1.
is pump operational?
It maybe necessary to have the operator run the pump to ensure
that it is functional. Also note any unusual characteristics
such as corrosion, and excessive noise, vibration, or heat
during operation.
What type ;of emergency power is available?
Emergency .power should be available to operate the pumps in
the event of a power failure. Use Key 3 to identify the type
of emergency power.
,, t
Is emergency power automatic or manual?
Determine .whether the emrgency power comes in automatically
when normal power is lost or if someone manually has to start
the emergency power generator. Also ensure that there is
sufficient^ fuel to operate the unit.
How often is emergency power tested?
The emergency power supply must be operated periodically to
ensure that it is operational. This should be done on a
regular schedule and under full load to ensure that it can
power the system. Note if there is sufficient fuel to provide
uninterrupted power.
Are safety guards in place for electrical connections and
mechanical connections?
All electrical and mechanical connections (electrical
switches, Isplices, rotating shafts, pulleys, chains and
sprokets, ;etc) should have guards to protect the operating
staff. 7 ] ' "" " " '" "" '"
What is the pump condition?
Note the condition of each pump. Record excessive noise,
vibration,! and heat. Also look for wobbly shafts, excessive
oil consumption, and other factors which would suggest that
the unit niay fail in the near future. Back up units and spare
.parts should be on hand.
Is facility properly protected against trespassing and vandalism?
The grounds should be fenced and all gates and outside doors
located to prevent the entrance of unauthorised individuals.
7. Describe the problems which need correction?
! ,.,.}
Once deficiencies are recorded, prepare a list of specific
recoramenations, (corrections, etc) which are necessary. You may
also wish to record a deadline for each of the recommended
actions. >
7-A
-------
Oft tailed cactors'of Pump
sollow-up inspection results and date:
A follow-up inspection should be scheduled as close to the
established deadline as possible. The purpose is to determine if
the recommendations have been acted upon and performed correctly.
-------
-------
Sanitary Survey
Storage arid Distribution Inspection
Date of inspection
Inspection conducted by
i. Name of System
2. PWS I.fJ. 4- '
3 i o r 3 g e
3. Identify appropriate information for individual storage tanks. (Use the
abbreviations key listed below for type)
Name of Tank Geographical Capacity AType Comments
Location (uallons)
Abbreviation Keys for Type
Mater ial
Concrete (C)
Steel (S)
Eerrocenient (E)
Other (0)
water
Raw (8)
Treated (I)
Elevation
On Ground (G)
U nd e r 3 r o un d (U)
Elevated (E)
Total number of days of supply
8-1
-------
-" S/D form
.- < Continued
! Yes No
5. Are sites protected .against flooding?
6. Are storage tanks structurally sound?
7. Are overflow lines, air vents, drainage
lines, and cleanout. pipes turned downward
or coveredp screened and terminated a
minimum of 3 diameters above the ground
or storage tank surface?
8. Are sites adquateiy,protected against
vandalism ? i
9, Are surface coatings in contact with
water acceptable? ,
" J.
10, Are tanks protectedjagainst corrosion?
.(
11. Can tanks be' isolated from system?
-i
Is ail treated wateij.storage covered?
1
How often are storage tanks cleaned?
"j
Are tanks disinfected af-ter repairs
are made? ;
Pi 51 r_i ,b u t j. o n_ System. \
15. Is thsrc a map of tile distribution
system available and' current?
16. Where is the map located?
17. Does the system currently nave water hours':
i 'd., A r s I E a k s r o u t i n e 1 y t e p a i r a d ?
iy. J.-T there a water ccmservaticn pian';
'-'.'j Is the water conservation plan in use and
voluntary or mandated?
- * A r e p i p e .1 i n '; -r, d i s i n J:' e c i e 0 a f t e r repairs
are wade? ' !;
-------
S/D Form
Continued
Is the system routinely monitored for
Microbiological quai-i-ty
Chemical quality
23. Is thars a cross connection control sroqran)?_ .._.
24, Are cross connections present in the
treatment system or distribution system7
If so, what corrective actions have
fa e e n o r d e r e d ": , .
25. What are the types and diameters of pipe used'
Type
Cast iron
PVC (Plastic)
Galvanised
Asbestos Cement
Copper-
Other (Specify)
26. Describe the problems which need correction.
27, Follow-up insoection results and date.
Siqnature of person conducting inspection
D a t e
-------
Detailed Factors of Form
Sto'age and Distribution Inspection
1. Name of system -
Enter the na i
as the munic
is located.
PSU I.D. -
e of the water sytenu Usually, this is the same name
Lpality or the geographical area in which the system
Enter the pu -lie water supply (FWSj) identification number for the
water system!, Each PWS is assigned an identification number by
the Regulatory Agency.
identify appropriate information for individual storage tanks.
abbreviations listed'below:
Record for each storage tank the following information:
Use the
Name -
Record the name or specific designation used for
tank.
Geographical'
Location .-
Capacity -
*Type -
Give the address, street number, cross roads,
community or other description which can serve
to help locate the tank.
Record the volume of water in gallons which the
tank will hold. To assist in calculating
capacity. See Appendix A-I page 1-3.
Using the abbreviations listed, record the type
of material of which the tank is constructed,
whether it contains raw or treated water, and is
it placed directly on the ground or partially
buried underground or elevated above ground.
Total number of days o!f supply
Using the tan'k capacities in Item 3, determine how many days total
supply are available if all tanks are full. Days of supply equals
the total gal-flans of water stored divided by the average daily
usage in gal Ions,
Days Supply = Av. Daily Usaqe
] (in gallons)
-------
Oeia lied tutors of b/D
LC'-itirnjed
S, Are site; protected against flooding?
Determine for each tank if the site- is below the expected flood
level. Record your observations under the appropriate comments
section in Item 3.
6, Are storage tanks structurally sound?
Look for erroded or cracking foundations and fpotings, rusted and
deteriorated metal structures, spoiling concrete (i.e. surface
layer peeling), etc,
7; Are overflow lines, air vsnts, drainage lines, and cleanout pipes turned
downward or covered, screened and terminated a minimum of 3 pipe diameters
above the ground or storage tank surface?
This is self explanatory and will ensure that unwanted .surface
runoff and precipitation do not enter the tank.
8. Are sites adequately protected aginst vandalism?
[n addition to' the considerations listed in Section VII-12. also
look for locks on hatch covers, ladder barriers to prevent
" ' unauthorised use, etc. The best-advice is to- imagine yourself as
a vandalHow would you get in illegally?
9, Are surface coatings in contact with water acceptable?
Record the name or type of coating used on the inside of the tank.
Check the specific type of coating material to ensure that the
material is not considered toxic for human consumption. Note"
Lead based paints and petroleum products such as tar are not
acceptable on the interiors of water storage tanks.
10. Are tanks protected against corrosion?
Determine what precautions are used to control tank corrosion.
Look for methods such as paint coatingsr cathodic protection, etc,
-------
Detailed Factors of 'S/D
Continued
11 Can tanks be isolated from system?
to determine
Use pipe schematics
-------
Detailed Factors of S/D
Continued
18. Are leaks routinely repaired?
consumers and operating staff can comment on this
question. Eiles on leaks (location,...etc.) are useful in
planning for system repairs or replacement.
19. Is there a water conservation plan?
Consumers and operating staff can provide insight not only to if
there is a plan, but also how well it is implemented. Consider
how well the plan is explained to the consumer, and how it is
promoted. Uhat are the incentives or penalities if a consumer
does not follow the water conservation plan?
20. Is there a water conservation plan in use, and voluntary or mandated?
Use the process described in Item 19 to determine how well the
plan works and whether it is voluntary or required.
21. Are pipe lines disinfected after repairs are made?
Pipe lines should be disinfected after all repairs using 50 ppm
chlorine solution for a minimum of 24 hours of contact time. See
Appendix B IV pages 1 and 2 for additional information on
disinfection of water pipelines.
22. Is the system routinely monitored for microbiological quality and chemical
quality?
Determine what tests are conducted to monitor the microbiological
and chemical quality of the water in the distribution system.
Also determine the frequency of the tests along with the results
to determine if the water quality meets established standards.
Also verify that the analysis is conducted according to standard
methods.
23. Is there a cross connection control program?
A cross connection is a physical connection between a potable
water system and nonpotable water. Only certain techniquest and
devices are approved to prevent the backflow and back siphonage of
nonpotable water into the potable system. A control program
should include both an inspection and device testing program as
well as a public education program.
8-7
-------
Are cross connections; present in the treatment system or distribution
system? (
Look for cross connections such as hoses in chemical solutions,
submerged inlets in chemical feeders, interconnecting plumbing
between public system and individual cisterns, etc. Recommend
corrective action such as air sap (cheapest) to more sophisticated
backflow'prei/entors and reduced pressure zone units which are
appropriate- :;.o the level of hazard, i.e. more hasard more absolute
the protection.
3- 8
-------
Detailed factors of S/D
Continued
25. What are the types and diameters of pipes used?
Record each type of pipe used and the diameters. See types of
pipes page 8-9.
26. Describe'the problems which need correction.
Once deficiencies are recorded,, prepare a list of specific
recommendations (corrections, etc.) which are necessary. You may
also wish to record a deadline for each of the recommended
actions.
27. Follow-up inspection results and date.
A fallow-up inspection should he scheduled as close to the
established deadline as possible. The purpose is to determine if
the recommendations have been acted upon and performed correctly.
8-9
-------
PIPES AND [VALVES: TYPES AND CHARACTERISTICS
The types of pipes and valves and their characteristics are summarised as
follows: , ]
Pij_e_s. I
1. Convey supply to points of use
2. Pipe sise relative to flow gp'm (gallons per minute) and distance
3. Types , ,
a. yaJvari_i_E_ed - Not recommended for underground use; subject to corrosion
from soil, acid water
t'« Cojjer. - Heavy -types; used underground; less sensitive to corrosion
c- P.iAst.i.c - Corrosion Jresistant; subject to puncture; subject to
deterioration by exposure to direct sunlight
d. Cjsi_Irjon/JDucjfc.y.e_Ir!o.n - Corrosion resistant; good hydraulic
characteristics; unlined pipe can be subject to iron rust deposits
e. Mt^s_t_Q_s_C,ej)).ejrt - Lightweight, corrsoion resistant; easily cut but
easily broken when handled; also, consider current concerns about
asbestos. "!
S. Lead. - Used in older; systems, particularly as service lines. No longer
approved under any circumstances due to possibility of contaimianting
tapwater. i
1. Control water flow I
2. Adjust water levels and pressures
3. Isolate sections of system for repair - - -
4. Types i '
* ^bJr!ilJiLt_y3.j.ve.s. stop' flow, of water.
b- £.bec.k...Va.l.y_e.s permit water to flow in one direction only.
c- LLa..w._kSr!i.r.5l_!i;?.l,y.B.5. provide uniform flow at varying pressures.
d- Se.Li.?l._.ya.Lye.s permit water to escape from the system to relieve
excessive pressure.
s- Llo.a.i_Valves, respond1 to high water levels to close an inlet pipe.
£' .i.L9.y.ol.l._y.-3.ry..?.?. provide a means to flush sediment from low points/
deadends in the,distribution system. -
9- A.l.yt.ud^e._ya.ljv_e_5 usedi;to shut off flow of water"'into storage tank at a
present level to avoid overflow and allow water to flow into tank after
... level drops. , .j
n- Ai.r_Reli.ef_Val.ves.' used at high points to release entrapped air.
i- H.VLlLa.Q.ks provide water for firefighting and to flush the system.
j. Ke.duced^Pressure_2one_yalves. used to correct specific cross connections.
'' .yj.9JJJJll_£r..?3.ke.r_y.a.l.yj£!J> allow air to enter the system to prevent back
shiphdhage". ' .1* ' ' ,
permit water to flow in one direction
only,
3-10
-------
APPENDIX A
MATHEMATICS AND CALCULATIONS
I. SURFACE AREAS AND VOLUMES
II. MULTIPLICATION TABLE
III. METRIC SYSTEM
IV. CONVERSION FACTORS
V. WATER ABBREVIATIONS
-------
'11, '
' i:
-------
I. SURFACE AREAS AND VOLUMES
A. Surface Areas
1. Circle
2. Rectangle '
3. Cylinder
A = TTr
rr
A = 1 x w
w
A = 2 (TTrr) + ZTT^rxh
[top & bottom] [side]
= 3.1416
r = radius =1/2 diameter
1 = length
w = width
h = height
Example I: What is the area of a circle with a diameter of 20
. centimeters?
In this case, the formula using a radius is more convenient
since it takes advantage of multiplying by 10.
Area, sq cm = Tf" (R, cm) (R, cm)
= 3.14 x 10 cm x 10 cm
= 314 sq cm
Example II: What is the area of a storage tank with a 50-foot radius
that is 20 feet high.
In this case, the formula using diameter,is more convenient.
A (sq ft) = 2 (3.1416 x 50 x 50) + 2 x 3.1416 x 50 x 20
=15,708 sq ft + 6283 sq ft
= 21,991 sq ft
Example III: Find the area of a rectangle if the length is 5 feet and the
width is 3.5 feet.
Area, sq ft = Length, ft x Width, ft
= 5 ft x 3.5 ft
= 17.5 sq ft
AI-1
-------
Example IV: The surface area of a settling basin is 330 square feet.
One side measures 15 feet. How long is the other side?
: A = L X W
330 sq f t = L ft x 15 ft
L ft x 15 ft = 330 sq ft Divide both sides of
15 -ft 15 ft equation by 15 ft.
'I
L ft 33° sq ft
15 ft
. i; = 22 ft
i1
Example V: How many"! square feet of surface area are in a- tank with a
diameter of 60 feet and a height of 20 feet. We could start
with the; top and bottom.
The area! of the top and bottom ends are both 'fT^x R x R
Area, sqi. f t = 2 ends (Tf5 (Radius, ft) (Radius, ft)
;= 2 x TT^x (30 sq ft) (30 sq ft)
= 5652 sq ft
The surface area of the wall must now be calculated.
i
The length has been found to always be TT^x D. In the case
of the tank, the length of the wall would be:
Length ft;. = (TT (Diameter, ft)
f \
! = 3.14 x 60 ft
; - 188.4 ft
Area would be :
Area, sq ft = Length, ft x Height, ft
, = 188.4 ft x 20 ft
i = 3768 sq ft
Outside Surface Area
to Paint | sq ft = Area of top and bottom,
-j sq. ft + Area of wall,
; sq ft
j = 5652 sq ft + 3768 sq ft
I = 9420 sq ft
-------
B. Volumes
Rectangle
Volumes are measured in three dimensions or in cubic units. To calculate
the volume of a rectange, the area of the base is calculated in square units
and then multiplied by the height. The formula then becomes:
V = L x W x H
Example: The length of a box is two feet, the width is 15 inches, and the
height is 18 inches. Find its volume.
V = 24 in x 15 in x 18 in
= 6480 cu in
Cylinder
The volume of a cylinder is equal to the area of the base multiplied by
the height.
V=TTRxRxH=0.785DxDxH
Example: A tank has a diameter of 100 feet and a depth of 12 feet. Find
the volume.
Volume, cu ft = 0.785 x (Diameter, ft) x (Diameter, ft) x Height, ft.
= 0.785 x 100 ft x 100 ft x 12 ft
= 94,200 cu ft .
AI-3
-------
-------
< II. MULTIPLICATION TABLE
1 2 3 4 5 6 7 8 9 10 11 12
2 4 6 8 1U 12 14 1.6 18 20 22 24
3 6 9 12 15 18 21 24 27 30 33 36
4 8 12 16 20 24 28 32 36 40 44 48
5 10 15 20 25 30 35 40 45 50 55 60
6 12 18 24 30 36 42 48 54 . 60 66 72
7 14 21 28 35 42 49 56 63 70 77 84
8 16 24 32 40 48 56 64 72 80 88 96
9 18 . 27 36 45 54 63 72 81 90 99 108
10 20 30 40 50 60 70 80 90 100 110 120
11 22 33 44 55 66 77 88 99 110 121 132
12 24 36 48 60 72 84 96 108 120 132 144
To use the multiplication table above use the following example of 5 x 6. Find
the number five in the left hand column and trace a horizontal line to the
right. Then find the number 6 in the top line an drop a vertical line down
from the 6. The point where the two lines cross is the answer (30).
AII-1
-------
-------
III. METRIC SYSTEM
The two most common systems of weights and measures are the English
system and the Metric system. Of these two, the Metric System is more popular
with most of the nations of the world. The reason for this is that the Metric
system is based on a system of tens and is therefore easier to remember and
easier to use than the English system.
PREFIXES USED IN THE METRIC SYSTEM
Prefixes
Micro
Milli
Centi
Deci
Unit
Deka
Hecto
Kilo
Mega
Symbol
m
c
d
da
h
k
M
Meaning
1/1 000 000 or 0.000 001
1/1000 or 0.001
1/100 or 0.01
1/10 or 0.1
1
10
100
1000
1 000 000
MEASURES OF LENGTH
The basic measure of length is the meter.
1 kilometer (km) = 1000 grams (gm)
1 meter (m) = 100 centimeters (cm)
I centimeter (cm) = 10 millimeters (mm)
MEASURES OF CAPACITY OR VOLUME
The basic measure of capacity in the Metric system is the liter. For
measurement of large quantities the cubic meter is sometimes used.
1 kiloliter (kL) = 1000 liters (L) = 1 cu meter (m2)
1 liter (L) = 1000 milliliters (mL)
AIII-1
-------
MEASURES OF WEIGHT
The basic unit of weight in the Metric system is the gram. One cubic
centimeter of water at maximum density weighs one gram, and thus there is a
direct, simple relation between volume of water and weight in the Metric
system. ;'
1 kilogram (kg)
1 gram (gm
1 milligram (mg)
1000 grams (gm)
1000 milligrams (mg)
lOpO micrograms (/!
-------
Therefore, 1 mg/L is equal to one tenthousandth of a percent, or
1% is equal to 10,000 mg/L
To convert mg/L to %, move the decimal point four places or numbers to the
left.
Working problems using milligrams per liter or parts per million is a part
of everyday operation in most water treatment plants.
Example Problems
Examples: Raw water flowing into a plant at a rate of five million pounds per
day is prechlorinated at 5 mg/L. How many pounds of chlorine are
used per day?
5 mg/L = 51bs Chlorine
million Ibs water
Chlorine
Feed, = Concentration, Ibs/M Ibs x Flow, Ibs/day
Ibs/day
5 Ibs 5 million Ibs
~ x
million Ibs day
= 25 Ibs/day
There is one thing that is unusual about the above problem and that is the
flow is reported in pounds per day. In most treatment plants, flow is reported
in terms of gallons per minute or gallons per day. To convert these flow
figures to weight, an additional conversion factor is needed. One gallon of
water weight 8.34 pounds. Using this factor, it is possible to convert flow in
gallons per day to flow in pounds per day.
Example: A well pump with a flow of 3.5 million gallons per day (MGD)
chlorinates the water with 2.0 mg/L chlorine. How many pounds
of chlorine are used per day?
Flow, Ibs/day = ^^ M^al ^ lb_
day gal
= 3.5 million gal 8.34 Ibs
day gal
= 29.19 million Ibs/day
a
Ibs/day
Chlo'rine
Feed, = Level, kg/L x Flow, M Ib/day
= 2'° mg x 29.10 million Ibs
million mg day
= 58.38 Ibs/day
AIII-3
-------
Remember that
1 me
'
vr M 11-
M mg ,!M Ib
They are identical ratios.
In solving the above problem, a relation was used that is most important
to understand and commit to memory.
Feed, Ibs/day = Flow, MGD~'x Dose. mg/L x 8.34 Ibs/gal
Example :
A chlorinator is set to feed 50 pounds of chlorine per day to a flow
of 0.8 MGD. Wtiat is the chlorine dose in mg/L?
Cone, or Dose, _
mg/L
Ibs/day
MGD x 8.34 Ib/gal
= _ 50lb/day _
0.80 MG/day x 8.34 Ib/gal
= 50 Ib
6.672 M Ib
7.5 mg/L, or 7.5 ppm
Example: A pump delivers: 500 gallons per minute to a water treatment plant.
Alum is added at 10 mg/L. How much alum is used in pounds per day?
Flow, MGD
Alum Feed,
Ibs/day
= Flow, GPM x 60 min/hr x 24 hr/day
= 500 gal 60 mph 24 hr
min hr day
= 720,000 gal/day
= 0.72 MGD
= Flow, MGD x Dose, mg/L x 8.34 Ibs/gal
0.72 M gal 10 mg 8.34 Ib
day M mg gal
.".;;;= 60.048 Ibs/day or about 60 Ibs/day
f WEIGHT-VOLUME RELATIONS
Another factor for the operator to remember, in addition to the weight of
a gallon of water, is the weight of a cubic foot of water. One cubic foot of
water weighs 62.4 Ibs. If ! these two weights are divided, it is possible to
determine th number of gallons in a cubic foot.
62.4 pounds /cu ft
"8.34 poundl/IaF" ~
gal/cu ft
AIII-4
-------
Thus we have another very important relationship to commit to memory.
8.34 Ib/gal x 7.48 gal/cu ft = 62.4 Ib/cu ft
It is only necessary to remember two of the above items since the thired
may be found by calculation. For most problems, 81/3 Ibs/gal and 71/2 gal/cu
ft will provide sufficient accuracy.
Example: Change 1000 cu ft of water to gallons.
1000 cu ft x 7.48 gal/cu ft = 7,480 gallons
Example: What is the weight of three cubic feet of water?
62.4 Ib/cu ft x 3 cu ft = 187.2 Ibs
Example: The net weight of a tank of water is 750 Ibs. How many gallons does
it contain?
750 Ib Qn ,
= 90 gals
8.34 Ib/gal
FORCE, PRESSURE, AND HEAD
In order to study the forces and pressures involved in fluid flow, it is
first necessary to define the terms used.
FORCE: The push exerted by water on any surface being used to confine it.
Force is usually expressed in pounds, tons, grams, or kilograms.
PRESSURE: The force per unit area. Pressure can be expressed in...many., ways,,
but the most common term is pounds per square inch (psi).
HEAD: Vertical distance from the water surface to a reference point below
the surface. Usually expresed in feet or meters.
An EXAMPLE should serve to illustrate these terms.
If water were poured into a one-foot cubical container, the FORCE acting
on the bottom of the container would be 62.4 pounds.
The PRESSURE acting on the bottom would be 62.4 pounds per square foot.
The area of the bottom is also 12 in x 12 in = 144 sq in. Therefore, the
pressure may also be expressed as:
Pressure, psi _ 62.4 Ib _ 62.4 Ib/sq ft
sq ft 144 sq in/sq ft
= 0.433 Ib/sq in
= 0.433 psi
AIII-5
-------
Since the height of the container is one foot, the HEAD would be one foot,
n /ooThS pressure in any {vessel at one foot of depth or one foot of head is
U.4.33 psi acting in any direction,
If the depth of water in the previous example were increased to two feet
the pressure would be: '
D = 2(62.4 Ib) _ 124; 8 Ib .
P .144 sq in ~ ~= °'
Therefore we. can see! that for every foot of head, the pressure increases
by 0.433 psi. Thus, the general formula for pressure becomes:
P, psi = 0.4333 (H. ft)
H = feet of head
p = pounds per square inch of pressure
P.lb/sq ft = 62.4 (H. ft)l H = feet of head
p = pounds per square foot of pressure
, ' ' , , i
\ FLOW RATE
If water in a one-foot wide channel is one foot deep, then the cross
sectional area of the channel is 1 ft x 1 ft = 1 sq ft.
If the velocity in this channel is 1 ft per second, then each second a
body of water 1 sq ft in area and 1 ft long will pass a given point. The
volume of this body of watj:er would be 1 cubic foot. Since one cubic foot of
water would pass by every i second, the flow rate would be equal to 1 cubic foot
per second, or 1 cfs. i
. To obtain the flow rate in the above example. the velocity was multiplied
by the cross -sectional area. This is another important general formula.
_ - Q = flow rate, cfs or cu ft/sec
Q ° V x A .'
.? V = velocity, ft/sec
; A = area, sq ft
Example: A rectangular channel 3 feet wide contains water 2 feet deep and
flowing at a velocity of 1.5 feet per second. What is the flow rate
in cfs? .;;
Q == V x A
Flow rate, cfs, == Velocity, ft/sec x Area, sq ft
. :f 1-5 ft/sec x 3 ft x 2 ft
i
= 9 cu ft/sec
All1-6
-------
Example;
Example:
Flow in a 2.5 foot wide channel is 1.4 ft deep and measures 11.2
cfs. What is the average velocity
In this problem we want to find the velocity. Therefore, we must
rearrange the general formula to solve for velocity.
V
Q
A
Velocity, ft/sec = Flow Rate, cu ft/sec
Area, sq ft
11.2 cu ft/sec
2.5 ft x 1.4 ft
= 11.2 ft/sec
3.5
= 3.2 ft/sec
Flow in an 8-inch pipe is 500 GPM. What is the average velocity?
Area, sq ft = 0.785 (Diameter, ft) (Diameter, ft)
= 0.785 (8/12 ft) (8/12 ft)
= 0.785 (2/3 ft) (2/3 ft)
= 0.785 (4/9 sq ft)
= 0.35 sq ft.
Flow, cfs
= Flow, gal/min x cu ft x 1 min
7.48 gal 60 sec
= 500 gal x cu ft x 1 min
min 7.48 gal sec
= 500 cu ft
448.8 sec
= 1.114 cfs
Velocity, ft.sec = Flow, cu ft/sec
Area, sq ft
= 1.114 cu ft/sec
0.35 sq ft
= 3.18 ft/sec
AIII-7
-------
Pumps
r',.
. Pressure :
Atmospheric pressure at sea level is approximately 14.7 psi. This
pressure acts in all directions and on all objects. If a tube is placed upside
down in a basin of water l;and a 1 psi partial vaccum is drawn on the tube, the
water in the tube will rise 2.31 feet.
NOTE: 1 ft of water = 0.'433 psi, therefore,
0.433
= 2;. 31 ft of water
The action of the pa'rtial vacuum is what gets water out of 'a sump or well
and up to a pump. It is not sucked up, but it is pushed up by atmospheric
pressure on the water surface in the sump. If a complete vacuum could be
drawn, the water would rise 2.31 x 14.7 = 33.9 feet; but this is impossible to
achieve. The practical limit of the suction lift of a positive displacement
pump is about 22 feet, and that of a centrifugal pump is 15 feet.
Work ..... !
Work can be expressed as lifting a weight a certain vertical distance. It
is usually defined in terms of foot-pounds.
Example: A 165-pound 'man runs up a flight of stairs 20 feet high. How much
work did he do?
Work, ft-lb = Weight, Ib x Height, ft
= 165 Ib x 20 ft ' '
= 3300 ft-lb
Power
°f
usually expressed in foot-pounds per
Example:
If the man in the above example runs up the stairs in three seconds,
now much power has he exerted?
Power, ft-lbs.sec = Work, ft-lb
Time, sec
= 3300 ft-lbs 60 sec
3 sec minute
= 66,000 ft-lb/min
-------
IV. CONVERSION FACTORS
Multiply By To Obtain
Bags or sacks-cement 94 .....Pounds-cement
Centimeters 0. 3937 Inches
0.01 Meters
10 Millimeters
B.T.U./min 12.96 Foot-lbs./sec.
/ " 0.02356 Horse-power
/ " 0.01757 Kilowatts
/ " 17.57 Watts
Centigrams 0.01 Grams
Centiliters 0.01 . Liters
Centimeters/second 1.969 Feet/min.
/ " 0.03231 Feet/sec.
Centimeters/second 0.036 Kilometers/hr.
/ " 0.6 Meters/min.
/ " 0.02237 , Miles/hr.
" ./ " 3.728x10-. Miles/min.
Cubic cemtimeters 3.531xlO~2 Cubic feet
6.102x10- Cubic inches
10 , Cubic meters
1.308x10-]? Cubic yards
2.6^2x10- Gallons
2.113x10-;; Pints .(liq.)
1.057x10- Quarts '.-(liq.)
4
Cubic feet.... 2.832x10 Cubic cms.
11 1728 Cubic inches
" 0.02832 Cubic meters
" 0.03704 Cubic yards
" 7.48052... Gallons
" ... . 28.32 Liters
" .....59.84 Pints (liq.)
Cubic feet/minute........... 472. 0 Cubic cms./sec.
11 0.1247 ..Gallons/sec.
" 0.4720 Liters/sec.
...62.43 Pounds of water/min.
Cubic feet/second. 0.646317 Million gals./day
/ " 448.831 Galloms/min.
AIV-1
-------
Multiply
By
To Obtain
Cubic inches. <, ..16.39...., Cubic centimeters
.,..5.787x10-5 Cubic feet
j... 1.639x10- Cubic meters
;, ..2.143x10-, Cubic yards
.,..4.329x10-2 Gallons
..1.639x10- Liters
...0.03463 Pints (liq.)
...0.01732 Quarts (liq.)
Cubic meters .. 10 Cubic centimeters
............. ..-jD.'jX...............Cubic IT eet
««««««««,.i. .61,023.... «»« Cubic inches
............« ..1.308 ............ Cubic yards
.............. 264.2...............Gallons
3
Cubic meters 10 Liters
...2113 Pints (liq.)
..1057 Quarts (liq.)
!' |
3
Cubic yards ,;..7.646x10 Cubic centimeters
" J..27 Cubic feet
*****«» *«.46,656. .....*..... Cubic inches
, . ,0.7646 Cubic meters
«**«.«* /OH. o. «.««*«*...loiters
" ....1616 Pints (liq.)
.. 807.9............... Quarts (liq. )
Feet 30.48 Centimeter
12 Inches
" 0.3048 Meters
" J.. 1/3 Yards
Feet of water. ...0.02950 Atmospheres
». .0.8826 Inches of mercury
...J..304.8 .Kgs./sq. meter
...... ....«!.. o 2 4 3............... Lb S./ s q. ft.
..0.4335 Lbs./sq. inch
Feet/min.. .0.5080 Centimeters/sec.
" / " '' ......+. .0.01667 Feet/sec.
" / " .,..0.01829 Kilometers/hr.
" / " :..0.3048 Meters/min.
" / " ........0.01136 , Miles/hr.
Feet/sec .30.48 Centimeters/sec.
/ " 1.097 Kilometers/hr.
" / " ..J... 0.5921 Knots
/ " 18. 29 Meters/min.
"' / " ......0.6818 Miles.hr.
" / " .....0.01136 Miles/min.
AIV-2
-------
Multiply By To Obtain.
Gallons 3785 Cubic centimeters
0.1337 v.Cubic feet
* 231. .a;Cubic inches
3.785x10- Cubic meters
4.951x10- Cubic yards
.3.785 Liters
8 Pints (liq.)
4 Quarts (liq.)
Gallons water 8.3453 Pounds of water
Gallons/min 2. 228xlO-3 Cubic feet/sec.
/ " > 0.06308 Liters/sec.
/ " 8.0208 ...Cu.'ft.
/ " » 8.0208 Overflow rate (ft./hr.)
Area (sq. ft.)
Gallons water/min 6.0086 Tons water/24 hrs.
Grams 0.03527 Ounces
3
Grams 2. 205x10- Pounds
Q
Grams/cm 5,600x10- Pounds/inch
Grams/cu. cm, 62.43 .Pounds/cubic foot
"' 0.03613 Pounds/cubic inch
Grams/liter.. 58.417 Grains/gal.
/ ...» 8.345 Pounds/1000 gals.
/ " 0.062427 Pounds/cubic foot
/ " 1000 Parts/million
Hectares 2.471...^ Acres
1.076x10 tSquare feet
Kilometers 105 Centimeters
.328^1. Feet
.10 Meters
.0.6214 Miles
.1094 Yards
AIV-3
-------
Multiply By To Obtain
Kilometers/hr..' .27. 78 Centimeters/sec.
«««»«......»«..)4.oo«..............Feet/min.
" J...0.9113 Feet/sec.
" " ....0.5396.n Knots
16.67 Meters/min.
" ....0.6214 Miles/hr.
3
Liters 10 Cubic centimeters
.0.03531 Cubic feet
.61.Q2 Cubic inches
.10- » Cubic meters
. 1.308x10- Cubic yards
.0.2642 Gallons
.2.113 Pints (liq.)
.1.057 Quarts (liq. )
Liters/min i.. .5.886x10-^ Cubic ft.-sec.
/ " ....4.403x10- Gals.-/sec.
Meters 100 Centimeters
"n 3.281 Feet
....................3".3/............... Inches
;« 10- Kilometers
i. ..10 Millimeters
,.. 1.094 Yards
Meters/min ;... 1. 667 Centimeters/sec.
/ .3.281....... .Feet/min.
/ " .,..0.05468 Feet/sec.
/ " ,..0.06 Kilometers/hr.
/ " ;. ..0.03728 Miles/hr.
Meters/sec ;. ..196.8... Feet/min.
/ ............,,,,..3.281.. Feet/sec.
/ " ,,..3.6 Kilometers/hr.
/ __ .,..0.06 Kilometers/min.
' ,...2.237 .Miles/hr.
/ " ...0.03728 Miles/min.
Microns '..... j.. 10-
.Meters
Miles . 1. 609xl05 Centimeters
...5280 Feet
" ...1.609 Kilometers
..1760 Yards
Miles/hr. , 44. 70 Centimeters/sec.
88 Feet/min.
.. 1.467 Feet/sec.
««1. 609 Kilometers/hr.
.-0.8684 Knots
1 * 26. 82 .Meters/min.
A1V-4
-------
Multiply By To Obtain
Milligrams 10- . Grams
Milliliters 10- Liters
Millimeters 0.1 Centimeters
0.03937 Inches
Milligrams/liter 1. . Parts/million
Million gals, /day 1. 54723 Cubic ft. /sec.
Ounces. 16 Drams
437.5 Grains
0.0625 Pounds
28. 349527 Grams
0.9115...* Ounces (troy)
. 2.790x10-;? Tons (long)
2.835x10- Tons (metric)
Ounces ( fluid ) 1.805 Cubic inches
0.02957 Liters
Parts/million 0.0584 Grains/U.S. gal.
/ " 0.07016 Grains/Imp, gal.
/ " .......8.345 Lbs./million gal.
Pounds 16.. Ounces
256 Drams
7000 Grains
0.0005 Tons (short)
453. 5924 Grams
Pounds of water 0.01602 Cubic feet
........... 27.68............... Cubic inches
0.1198 Gallons
Pounds/cubic foot 0.01602 Grams/cubic cm.
/. " " 16.02..... Kgs./cubic meter
/ " " 5.787x10- Lbs./cubic inch
Pounds/sq. inch 0.06804 Atmospheres
/ " " .2.307 Feet of water
/ " " 2.036 Inches of mercury
/ " " 703.1 Kgs./sq. meter
Square inches. ...6.452....,=.........Square centimeters
o 6.944x10- Square feet
645.2 Square millimeters
Square miles 640 , Acres
" 27.88xlOb Square feet
..2. 590 Square kilometers
" 3.098x10 Square yards
AIV-J
-------
Multiply ; By To Obtain
Square feet.. 2. 296xlO-5 Acres
929.0 Square centimeters
.. j. .144 Square inches
" .. .........!..0.09290... Square meters
" 3.587x10- Square miles
. 1 /9 Square yards
Temp. (°C) + 17.78 1.8 Temp. (°F.)
(°F) + 460 .;..! Abs. temp. (°F.)
"-32 .......5/9 Temp. (°C.)
Tons ( short) .!'.. 2000 Pounds
'.. 32000 Ounces
.:.'. 907.18486 Kilograms
Yards .> . 91.44 Centimeters
3 Feet
..36 Inches :
!'. .0.9144 Meters
-------
V. WATER
fie acre
ac-ft acre-feet
af acre feet
amp ampere
C degrees Celsius
cfm cubic feet per minute
cfs cubic feet per second
Ci Curie
cm centimeter
cu ft cubic feet
cu in cubic inch
cu m cubic meter
cu yd cubic yard
o
F degrees Fahrenheit
ft feet or foot
ft-lb/min foot-pounds per minute
g gravity
gal gallon
gal/day gallons per day
gm gram
GPD gallons per day
GPM gallons per minute
gpg grains per gallon
gr grain
ha hectare
HP horsepower
ABBREVIATIONS
km
kN
kW
KWh
L
Ib
Ibs/sq in
m
M
M
rag
mg/L
MGD
mL
min
mm
N
ohm
Pa
pCi
psf
psi
/
psig
ppb
ppm
sec
kilometer
kilonewton
kilowatt
kilowatt-hour
liter
pound
pounds per square inch
meter
mega
million
milligram
milligram per liter
million gallons per day
milliliter
minute
millimeter
Newton
ohm
Pascal
picoCurie
pounds per square foot
pounds per square inch
pounds per square inch gage
parts per billion
parts per million
second
AV-1
-------
hr
in
k
kg
hour
inch
kilo
kilogram
sq ft
sq in
W
square feet
square inches
watt
AV-2
-------
APPENDIX B
DISINFECTION
I. Disinfecting by the Chlorine Method
II. Emergency Disinfection
III. Disinfection of Wells
IV. Disinfection of Water Lines
V. Disinfection of Gravity Storage Tanks
-------
'li
t
-jf
-------
I. DISINFECTION BY THE CHLORINE METHOD
The amount of chlorine needed to disinfect water is quite small - usually about
1 to 5 parts of chlorine to 1,000,000 parts of water. This is commonly referred to
as parts per million, or "ppm." If water contained no impurities, such as sulfur,
or iron, or organic particles from plants and animals that "use up" chlorine, the
same amount could be used for treating all water supplies. But, water is almost
certain to contain one or more of these. For that reason, it is necessary to adjust
the amount of chlorine to meet the needs of each water supply.
The chlorine supply can come from several sources. For home-size chloriation
units the chlorine is available in the form of "hypochlorites" - diluted or
low-grade forms of chlorine. There are two:
Sodium hypochlorite - Chlorine solutions of sodium hypochlorite (NaOCl), are
available as 5.25% chlorine (common household chlorine bleach) and 15%.
solutions available in 5 gallon carboys and larger quantities.
- 1 gallon of 5.25% contains 0.42 Ibs. of available chlorine
- 1 gallon of 15% contains 1.25 Ibs. of available chlorine
The chlorine solution mixes easily with water to make stock water solutions of
the desired strength.
Calcium hypochlorite - Granular form as high test calcium hypochlorite
containing 65% available chlorine, commonly marketed as HTH, PitChlor,
Perchloron, etc.
(Chlorine gas, could be used, but it is costly, dangerous to handle, and
requires close attention.)
Sodium hypochlorite is a water-and chlorine solution commonly used for laundry
bleaches. It is available in two strengths - "domestic" or "commercial." Domestic
laundry bleach is by far the most popular. It can be purchased from grocery stores
under such trade names as Clorox, Purex, and Oxol. It contains only about 5.25
per cent of available chlorine.
It is only the available chlorine portion that counts in figuring the parts per
million. But, even this small amount of chlorine treats a large quantity of water.
For example, if you chlorinate at the rate of 1 ppm, one gallon of laundry bleach
will treat about 50,000 gallons of water. If you treat at the rate of 5 ppm, one
gallon of laundry bleach will treat about 10,000 gallons of water.
Commercial laundry bleach can be purchased from chemical supply houses and from
some hardware stores in 5-gallon containers. It contains from 10 to 19 per cent
available chlorine, so smaller quantities of it can be used for treatment compared
to domestic laundry bleach. For larger water systems, the commercial-strength
bleach is usually more economical.
BI-1
-------
Some producers of hypochlorite are now -including additional cleaning agents in their
hypochlorite solutions. These are not considered a health problem, but they can
cause the water to have a bad taste.
Calcium hypochlorite is-available in powder and tablet form under such trade
names as B-K Powder, H.T.H.,'Perchloron, and Pittchlor. It contains 30 and 65
per cent active chlorine by weight. It is used to a very limited extent due to its
tendency to form deposits that interfere with proper operation of the chlorinator
unit.
The example on p. BI-3 '.illustrates a typical hypochlorinator comprised of a
diaphragm pump and a hyppchlprlte reservoir.
BI-2
-------
Example of a Hypochlorinator
Note - - Fill to center of oil level window
Diaphragm Pump
Mounting
Stand
Clamping ring
Coupling Nut
JVV-TTj
DETAIL "A"
Tubing
This tube should not
extendbeyond center
of main
Point of Application
Weight to keep while submerged
Filter to remove deposits
Bl-3
-------
-------
II. EMERGENCY DISINFECTION
When the water supply system is interrupted by natural or other forms of
disaster, limited amounts of water may be obtained by emergency disinfection.
There are two general methods by which small quantities of water can be
effectively disinfected. One method is by boiling. It is the most positive method
by which water can be made bacterialogically safe to drink. Another method is
chemical treatment. If applied with care, certain chemicals will make most waters
free of harmful or pathogenic microorganisms.
When emergency disinfection is necessary, the physical condition of the water
must be considered. The degree of disinfection will be reduced in water that is
turbid. Turbid or colored water should be filtered through clean cloths or allowed
to settle, and the clean water drawn off before disinfection. Water prepared for
disinfection should be stored only in clean, tightly covered, noncorrodible
containers.
Methods of Emergency Disinfection
1. Boiling. Vigorous boiling for 1 full minute will kill any disease-causing
bacteria present in water. The flat taste of boiled water can be improved
by pouring it back and forth from one container to another, by allowing it
to stand for a few hours, or by adding a small pinch of salt for each
quart of water boiled.
2. Chemical Treatment. When boiling is not practical, chemical disinfection
should be used. The two chemicals commonly used are chlorine and iodine.
a. Chlorine
(1) Chlorine Bleach. Common household bleach contains a chlorine
compound that will disinfect water. The procedure to be followed
is usually written on the label. When the necessary procedure is
not given, one should find the percentage of available chlorine
on the label and use the information in the following tabulation
as a guide:
Drops per
Available chlorine (1) quart of clear
water (2)
1% 10
4-6% 2
7-10% . 1
(1) If strength is unknown, add 10 drops per quart
to purify.
(2) Double amount for turbid or colored water.
BII-1
-------
The treated water should be mixed thoroughly and allowed to stand for 30
minutes. The water should have a slight chlorine odor; if not repeat the
dosage and allow the water to stand for an additional 15 minutes. If the
treated water has too strong a chlorine taste, it can be made more palatable
by allowing the water to s|tand exposed to the air for a few hours or by pouring
it from one clean container to another several times.
(2) Granular Calcium Hypochlorite. Add and dissolve one heaping
teaspoon of high-test granular calcium hypochlorite
(approximately 1/4 ounce for each 2 gallons of water. This
mixture will produce a stock chlorine solution of
approximately 500 mg/1, since the calcium hypochlorite has
an available chlorine equal to 70 percent of its weight. To
disinfect water, add the chlorine solution in the ratio of
one part of chlorine solution to each 100 parts of water to
be treated. This is roughly equal to adding -1 pint (16 oz.)
of stock chlorine solution to each 12.5 gallons of water to
be disinfected. To remove any objectionable chlorine odor,
aerate the water as described above.
(3) Chlorine Tablets. Chlorine tables containing the necessary
dosage ,for drinking water disinfection can be purchsed in a
commercially prepared form. These tablets are available
from drug and sporting goods stores and should be used as
stated;in the instructions. When instructions are not
available, use one tablet for each quart of water to be
purified.
b. Iodine .j
(1) Tincture of Iodine. Common household iodine from the
medicine chest or first aid package may be used to disinfect
water. ', Add five drops of 2 percent United States
Pharmacopeia (U.S.P.) tincture of iodine to each quart of
clear water. For turbid water add 10 drops and let the
solution stand for at least 30 minutes.
(2) Iodine Tablets. Commercially prepared iodine tablets
containing the necessary dosage for drinking water
disinfection can be purchased at drug and sporting goods
stores. They should be used as stated in the instructions.
When instructions are not available, use one tablet for each
quart of water to be purified.
Water to be used for drinking, cooking, making any prepared drink, or
brushing the teeth should be properly disinfected.
BII-2
-------
III. DISINFECTION OF WELLS
All newly constructed wells should be disinfected to neutralize
contamination from equipment, material, or surface drainage introduced during
construction. Every well should be disinfected ^promptly after construction or
repair.
An effective and economical method of disinfecting wells and appurtenances
is that of using calcium hypochlorite containing approximately 65-percent
available chlorine. This chemical can be purchased in granular or tablet form
at hardware stores, swimming pool equipment supply outlets, or chemical supply
houses.
When used in the disinfection of wells, calcium hypochlorite should be
added in sufficient amounts to provide a dosage of approximately 100 mg/1 of
available chlorine in the well water. This concentraton is roughly equivalent
to a mixture of 2 ounces of dry chemical per 100 gallons of water to be
disinfected. Practical disinfection requires the use of a stock solution. The
stock solution may be prepared by mixing 2 ounces of high-test hypochlorite
with 2 quarts of water. Mixing is facilitated if it is added with a small
amount of water and stirred to a smooth watery paste free of lumps. CAUTION:
Never add water to granular calcium hypochlorite. The reaction causes heat and
could result in an explosion. Always add strong (granular chlorine powder to
weak (water). It should then be mixed with the remaining quantity of water.
The stock solution should be stirred thoroughly for 10 to 15 minutes prior to
allowing the inert ingredients to settle. The clearer liquid containing the
chlorine should be used and the inert material discarded. Each 2 quarts of
stock solution will provide a concentration of approximately 100 mg/1 when
added to 100 gallons of water. The solution should be prepared in a thoroughly
clean utensil; the use of metal containers should be avoided, if possible, as
they are corroded by strong chlorine solutions. Crockery, glass, or
rubber-lined containers are recommended.
Where small quantities of disinfectant are required and a scale is not
available, the material can be measured with a spoon. A heaping tablespoonful
of granular calcium hypochlorite weighs approximately 1/2 ounce.
When calcium hypochlorite is not available, other sources of available
chlorine, such as sodium hypochlorite (12-15 percent of volume), can be used.
Sodium hypochlorite,which is also commonly available as liquid household
bleach with 5.25 percent available chlorine, can be diluted with one part of
water to produce the stock solution. Two quarts of this solution can be used
for disinfecting 100 gallons of water.
Stock solutions of chlorine in any form will deteriorate rapidly unless
properly stored. Dark glass or plastic bottles with airtight caps are
recommended. Bottles containing solution should be kept in a cool place and
protected from direct sunlight. If proper storage facilities are not
available, the solution should always be prepared fresh immediately before use.
Commercially available household bleach solutions, because of their convenience
and usual reliability as to concentration or stength, are preferred stock
solutions for disinfecting individual water supplies.
Tables on pages BIV-4, BIV-5, BV-2, and BV-4 show quantities of
disinfectants to be used in treating wells.
BIII-1
-------
r
Testing for Chlorine Residuals
' -I
The amount of chlorine] remaining in the water system (chlorine residual)
is determined by a relatively simple test commonly called the DPD colorimetric
test, short for the chemical name N, N-d (Diethyl-p-phenylene-diamine). The
test may be done under "fie!Ld" conditions using pillow reagents which are
placed along with 100 ml of', sample into a special test tube provided with DPD
kits. The presence of free: chlorine residual produces a violet color which is
compared with color standards to determine the quantity present.
If you are disinfecting clear wells, distribution reserviors or mains and
very high chlorine residuals must be measured, a drop-dilution technique can be
used to estimate the chlorine residual. The procedure is as follows:
1. Add 10 mL of distilled water and one powder pillow of DPD reagent (or 0.5
mL of DPD solution) to the sample tube of the test kit.
2. Add a sample of the water being tested on a drop-by-drop basis to the
sample tube until a color is produced.
3. Record the number of drops added to the sample tube. Assume one drop
equals 0.05 mL. i
4. Determine the chlorine residual in the sample as a result of the color
produced and record the residual in miligrams per liter.
EXAMPLE ;
The recorded chlorine residual is 0.3 mg/L. Two drops of sample produced
a chlorine residual of 0.3 mg/L in 10 mL of distilled water. Assume 0.05 mL
per drop.
Known Unknown
Chlorine Residual, mg/L =0.3 mg/L Actual Chlorine Residual,
Sample Volume, drops ; = 2 drops mg/L
Distilled Water, mL =. 10 mL
Calculate the actual residual in milligrams per liter.
Actual Chlorine _ (Chlorine Residual, mg/L)(Distilled Water, mL)
Residual, mg/L ] (Sample Volume, drops)(0.05 mL/drop)
__ (0.3 mg/L)(10 mL)
(2 drops)(0.05 mL/drop)
;|30 mg/L
BIII-2
-------
Table V. - Quantities of calcium hypochlorite, 65 percent (rows A) and liquid household
bleach, 5.25 percent (rows B) required for water well disinfection
Depth of
water in
well (ft.)
5
10
15
20
30
40
60
80
100
150
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
2
1T
1C
1T
1C
1T
1C
1T
1C
1T
1C
1T
1C
1T
1C
1T
1C
2T
1C
3T
2C
3
1T
1C
1T
1C
1T
1C
1T
1C
1T
1C
1T
1C
2T
1C
3T
1C
3T
2C
5T
2C
Well diameter (in.)
4
1T
1C
1T
1C
1T
1C
1T
1C
2T
1C
2T
1C
3T
2C
4T
2C
5T
3C
8T
4C
5
1T
1C
1T
1C
1T
1C
2T
1C
3T
1C
4T
2C
5T
3C
7T
4C
8T
1Q
4oz.
2Q
6
1T
1C
1T
1C
2T
1C
3T
1C
4T
2C
6T
2C
8T
4C
9T
1Q
4oz.
1.5Q
6oz.
2.5Q
8
1T
1C
2T
1C
3T
2C
4T
2C
6T
4C
8T
1Q
4oz.
2Q
5oz.
2Q
7oz.
2.5Q
10oz.
4Q
10
2T
1C
3T
2C
5T
3C
6T
4C
3oz.
1.5Q
4oz.
2Q
6oz.
3Q
8oz.
3.5Q
10oz.
4Q
1 Ib.
6Q
12
3T
1C
5T
2C
8T
4C
3oz.
1Q
4oz.
2Q
6oz.
2.5Q
9oz.
4Q
12 oz.
5Q
1 Ib.
6Q
1.5 Ib.
2.5G
16
5T
2C
8T
1Q
4oz.
2Q
5oz.
2.5Q
8oz.
4Q
10 oz.
4.5Q
20
6T
4C
4oz.
2Q
6oz.
2.5Q
8oz.
3.5Q
12oz.
5Q
1 Ib.
7Q
24
3 oz.
1Q
6oz.
3Q
9oz.
4Q
28
4oz.
2Q
8oz.
4Q
12oz.
5Q
32
5oz.
3Q
10 oz.
4Q
1 Ib.
6Q
36
7oz.
3Q
13 oz.
6Q
1.5lb
2G
42
9oz.
4Q
1.5lb.
8Q
1.5 Ib.
3G
48
12oz.
2Q
1.5lb.
2.5G
2lb.
4G
CD
Quantities are indicated as: T = tablespoons; oz. = ounces (by weight); C = cups; Ib. = pounds; Q = quarts; G = gallons
NOTE: Figures corresponding to rows A are amounts of solid calcium hypochorite required; those corresponding to row:
amounts of liquid household bleach.
-------
-------
IV. DISINFECTION OF WATER LINES
Even under the best conditions, the construction of new water lines
subjects the interior of the pipes and fittings to possible serious
contamination. The repair of faulty or ruptured water lines and fittings
usually occurs under adverse conditions and the threat of contamination is ever
present.
Before being placed in service, all new mains and repaired portions of, or
extensions to, existing mains shall be thoroughly flushed then chlorinated with
not less than fifty parts per million (50 ppm) of available chlorine. Chlorine
gas or seventy percent high-test calcium hypochlorite can be used. Note
cautions about the handling of chlorine gas.
Water from the existing distribution system or other source of supply
shall be controlled so as to flow slowly into the newly laid pipeline during
the application of chlorine. The solution shall be retained in the pipeline
for not less than twenty-four (24) hours and then flushed thoroughly with a
potable water of satisfactory bacteriological quality before starting sampling
program. During construction, precautions should be taken to avoid unnecessary
contamination.
Disinfection is commonly accomplished by one or four methods. All are
descrsibed in an American Water Works Association manual on Water Main
Disinfection, AWWA C601-68.
Continuous Feed Method
This method has an advantage for disinfection of long sections of pipe.
The disinfection, is accomplished after construction by injecting chlorine
solutions (either a gas chlorinator or hypochlorinator may be used) into the
pipe through a corporation cock or other fitting. The line is first flushed to
remove accumulated material. The chlorine dose is usually 50 mg/1 with a 24
hour contact period. The chlorine solution is injected as the line is being
filled. This method requires careful control and specialized equipment and
should not be attempted by inexperienced contractors or repair crews.
Slug Method
This method is similar to the previous method but employs high doses as
high as 500 mg/liter-with 1/2 hour retention. It is particularly applicable
for large diameter water mains and where the pipe must be put into service
without long delays.
Tablet Method
Calcium hypochlorite (65% available chlorine) is prepared by several firms
in tablet form under various labels. A swimming pool supply store is a good
source. These tablets are attached on the inside of the pipe (top side) as the
line is being laid with an adhesive. This method is considered superior to the
use of granular calcium hypochlorite which will flush away quickly before
dissolving. The water line should be filled slowly to reduce the chance of
flushing away the tablets. The method has some disadvantages: (1) The line
cannot be flushed before disinfection, (2) the tablets will not readily
dissolve at water temperatures below 41 F (5 C), and (3) the tablets are
difficult to insert in small diameter pipes.
BIV-1
-------
The water line should be filled slowly and tested at the extreme end until
a strong chlorine solution is present. Allow the chlorinated water to stand in
contact with the pipe for t:he full retention period. Then flush until the
chlorine residual by the DPD test shows a residual of 1.0 mg/1 or less. A
sample of water from the disinfected line should be collected for coliforra test
by an approved laboratory.; If the test indicates ineffective disinfection, it
must be repeated. The tables om pages BIV-4 and BIV-5 provide chlorine
requirements for various sizes of pipes.
Emergency Repairs and Disinfection
Where a short section!of pipe or a fitting must be repaired and placed
into immediate service, the section may be thoroughly swabbed with full
strength 5.25% sodium hypochlorite (common household bleach) during the repair
before installation. Care should be taken to insure complete coverage of all
inner surfaces.
Caution on the Storage and Use of Calcium Hypochlorite
Calcium hypochlorite is a highly reactive chemical when wet and should be
stored in dry places and away from organic substances as violet reactions,
including explosion and fire, may result. Potential contaminates include soap
products, cleansing oils, mineral oils, petroleum products, food and beverages,
paper and similar materials. Since the product is readily purchasable, avoid
storing large quantities. Avoid storage in direct sunlight. Note: When
mixing with water always add strong (calcium hypochlorite) to weak (water).
The reverse could be cause a violent reaction.
Caution on the Storage and Use of Chlorine Gas
Chlorine gas feed and storage shall be enclosed and separated from other
operating areas. The chlorine room shall be provided with a shatter resistant
inspection window installed in an interior wall or an inspection window in the
door. It shall be constructed in such a manner that all openings between the
chlorine room and the remainder of the plant are sealed, and provided with
doors assuring ready means of exit and opening only to the building exterior.
Full and empty cylinders of chlorine gas shall be isolated from operating
areas, restrained in position to prevent upset, stored in rooms separate from
ammonia storage, and stored in areas not in direct sunlight or exposed to
excessive heat.
When chlorine gas is used, the room shall be constructed such that
(a) Each room shall have a ventilating fan with a capacity which provides
one complete airichange per minute when the room is occupied.
(b) The ventilating fan shall take suction near the floor as far as
practical from the door and air inlet, with the point of discharge so
located as not to contaminate air inlets to any rooms or structures.
(c) Air inlets shall be through mechanical louvers near th ceiling,
BIV-2
-------
(d) Switches for fans and lights shall be outside of the room, at the
entrance. A signal light indicating fan operation should be provided
at each entrance when the fan can be controlled from more than one
point;
(e) Vents from chlorine feeders and chlorine storage areas shall
discharge to the outside atmosphere, above grade and away from inlet
vents.
Respiratory protection equipment, meeting the requirements of the National
Institute for Occupational Safety and Health (NIOSH) shall be available where
chlorine gas is handled, and shall be stored at a convenient location, but not
inside any room where chlorine is used or stored. The units shall use
compressed air, with at least a 30 minute capacity.
A bottle of ammonium hydroxide, 56 per cent ammonia solution, shall be
available for chlorine leak detection; where ton containers are used, a leak
repair kit approved by the Chlorine Institute shall be provided.
A least one pair of rubber gloves, dust respirator of a type certified by
National Institute of Occupational Safety and Health for toxic dusts, an apron
or other protective clothing and goggles or face mask shall be provided for
each operator.
BIV-3
-------
"LINE DISINFECTION USING CHLORINE TABLETS"
Chlorine Tablets Required to Produce 50 mg/1 Concentration of Chlorine in
Pipe Sections of Various Lengths and Diameters (AWWA C 601 - 68), Retention
Period of 24 hours.
Length of Pipe
Section in Feet
13 or less
18
20
30 ;
i1
40 ,
Diameter
2
1
1
1
1
1
4
1
1
1
2
2
in Inches
6
2
2
2
3
4
8
2
3
3
5
6
Notes:
Based upon tablets of 3-3/4 grams of available chlorine.
Retention period is 24 hours with above doses.
Double the number of tablets for 100mg/l dose and 12 hours
retention.
Use 4 times the number of tablets for 200 mg/1 dose and 12
hour retention.
For pipes less than 2 inches diameter, use the 2 inch
diameter pipe dose.
BIV-4
-------
CHLORINE REQUIREMENTS FOR VARIOUS SIZES OF PIPE AND CHLORINE DOSAGE
OF 10 MG PER LITER
Size
Inches
4
6
8
10
12
14
16
20
24
30
36
48
Contents in a
100-Foot Section
Gallons
65
146
261
408
588
800
1044
1632
2350
3672
5288
9402
Pounds of Chlorine
Required for Each
100 foot of main
to give 10 mg/L.
0.005
0.012
0.022
0.034
0.048
0.066
0.086
0.136
0.196
0.305
0.440
0.783
Length of Pipe
per ounce of
chlorine required to
give 10 mg/L.
1149.4
510.8
287.4
183.9
127.7
93.8
71.9
46.0
31.9
20.4
14.2
8.0
The above figures are based on 100 percent chlorine.
1. To find the dosages for chlorine compounds containing less than 100
percent chlorine, divide the pounds of chlorine required by the
percentable of chlorine in the compound and multiply by 100. For example
if HTH (65%) grade is used as the source of chlorine, the number of pounds
for a 12-inch pipe will be .048 x 100 = .074 Ibs.
.65
2. To find the length of pipe per ounce of chlorine for chlorine compounds
containing less than 100% chlorine, multiply the length of pipe shown on
the table by the percentage of chlorine in the compound and divide by 100.
For example if HTH (65%) grade is used as the source of chlorine, the
length of 12 inch pipe per ounce if HTH will be 127.7 x 65 = 83.0 ft.
100
3. Pounds of chlorine per 24 hours to apply to give dosage of 10 mg/L. =* Flow
in g.p.m. x 0.12. Example: 700 gpm x .12 = 84 Ibs/day chlorine.
4. The calculations are for dosages of 10 mg/L/ chlorine. For smaller
dosages divide the figures given by the correct factor, and for larger
dosage multiply the figures by the necessary factor.
Example: 700 gpm at a dosage of 25 ppm
700 gpm x .12 = 84 Ibs x 25 - 210 Ibs/day
10
BIV-5
-------
-------
V. DISINFECTION OF GRAVITY STORAGE TANKS
After construction and before use, the storage tank must be disinfected to
destroy micro-organisms which may be present. The tank interior must first be
cleaned to remove dirt and loose material.
Large tanks may be disinfected by the direct application of a chlorine
solution to the inner surface by means of a thoroughly cleaned garden type
spray can. A spray can which has been previously used for a spraying toxic
chemicals, must not be used. Spray all inner surfaces with a 200 mg/L solution
of chlorine made by adding 2 fluid ounces (59 ml) of 5.25% chlorine bleach
(common household sodium hypochlorite bleach) to 4 gallons (30 liters) of clean
water. The solution may also be brushed on th surfaces. The chlorine solution
should remain on the surface for at least 2 hours. The tank should be
ventilated to avoid inhalation hazards. After that the tank may be filled an
tested as stated below.
Disinfection may also be accomplished by adding chlorine solutions to the
structure as it is being filled. First determine the capacity of the tank in
gallons. Add 2 quarts of 5.25% chlorine bleach for each 100 gallons of
capacity for a 200 mg/L dose. The Table on page BV-2 provides quantities of
sodium hypochlorite (5.25%) for disinfection at 1 ppm. High test calcium
hypochlorite 65% available chlorine may also be used. Common forms are HTH and
Perchloron. Use 1/2 Ibs. for each 1000 gallons of tank capacity. Mix a slurry
in a plastic pail and add to the tank as it is being filled. After at least 2
hours of contact, the tank may be drained. Cut the dose in half for 100 mg/L
dose and increase the contact time to 12 hours. A 50 mg/L dose (1/4 of above)
may be used with a 24 hour retention time.
The Table on page BV-3 provides information on how much of a chlorine
compound is necessary to produce a one percent solution.
The Table on page BV-4 provides the amount of a chlorine compound
necessary to produce 10 ppm chlorine per thousand gallons of water.
A series of dosage calculations and sample calculations are provided at
the end of this section.
BV-1
-------
QUANTITIES OF SODIUM HYPOCHLORITE (5.25%)
FOR DISINFECTION AT 1 rog/L
1,000 gal. 2.44 oz.
2,000 gal. , 4.88 oz.
3,000 gal. 7.32 oz.
4,000 gal. " " '\ 9.76 oz.
5,000 gal. 12.2 oz.
6,000 gal. 14.64 oz.
7,000 gal. : 17.08 oz.
8,000 gal. 19.52 oz.
9,000 gal. 21.96 oz.
10,000 gal. 24.4 oz.
20,000 gal. 48.8 oz.
30,000 gal. I 73.2 oz.
40,000 gal. 97.6 oz.
50,000 gal. 122.0 oz.
60,000 gal. , 146.4 oz.
70,000 gal. 170.8 oz.
80,000 gal. 195.2 oz.
100,000 gal. 244.0 oz.
BV-2
-------
TABLE II-8
MATERIAL FOR DISINFECTION. OF SMALL QUANTITIES OF WATER
Amount material to dissolve in one pint of water to make
1% solution
Material
Ounces
Grams
Tablespoons Level
Full
Chlorine Gas
0.16
4.5
Calcium Hypochlo-
rite 0.26 7.3
H.T.H.
or Perchloron (65%)
Powder
B-K-(50%)
Powder 0.33 9.3
Chlorinated Lime 0.66 18.7
(25%) Powder
Sodium Hypochlo- 1.38 39.1
rite (12%) .._.
Liquid
Clorox (5%) 3.33 94.3
Liquid
Purex (3%) 5.52 156.4
Liquid
1.08 or 1.1
1.4
2.7
2.6
6.3
10.4
Zonite (1%) Stock solution is 1%
Liquid
NOTE: 19 milliliters or 1 1/4 tablespoons full of any of the above 1%
solutions added to five gallons of water is equivalent to 10 p.p.m. Chlorine,
75 drops of any of the above 1% solutions added to one gallon of water is
equivalent to 10 mg/L Chlorine.
(1) 1% = 10,000 ppm (mg/L)
Remember
Vl Cl = V2 C2
BV-3
-------
TABLE II-9
AMOUNT 01? MATERIAL PER 1000 GALLONS OF WATER
TO PRODUCE 10 mg/L CHLORINE SOLUTION
% Chlorine in
Material Material
Chlorine Gas 100
Calcium Hypo-
chlorite,
H.T.H. or 65
Perchloron
Powder
B-K Powder 50
Chlorinated 25
Lime Powder
Sodium Hypo- 12 !
chlorite Liquid
Clorox Liquid 5
Purex Liquid 3
Amount material to use
Ounces . Grams
1.33 37.69
2.05 57.98
2.66 75.38
5.34 151.33
11.08 314.00
Approx. 2/3
26.66 755.54
Approx. 1 1/2
44.33 1,256.31
Approx. 2 2/3
pint
pints
pints
Zonite Liquid
133.00
3,769.22
Approx. 8 pints
BV-4
-------
APPENDIX C
REFERENCES
-------
-------
SUGGESTED REFERENCES
1. Hater Treatment Plant Operations, Volume I
Water Treatment Plant Operations, Volume II
Hater Supply System Operation
Available from: Kenneth Kerri
Department of Civil Engineering
California State University, Sacramento
6000 J Street
Sacramento, CA 95819-2694
(Phone: 916-454-6142)
Price: $30.00 per manual
2. Manual of Water Utility Operations
Available from: Texas Water Utilities Association
6521 Burnet Lane
Austin, TX 78757
Price: $17.00
3. A Manual of Instruction for Hater Treatment Plant Operators
Available from: Health Education Services, Inc.
P. 0. Box 7126
Albany, NY 12224
Price: $3.13
4. Planning for an Individual Water System
Available from: American Association for Vocational
Instructional Materials
Engineering Center
Athens, GA 30602
Price: $7.65
5. Water Systems Handbook
Available from: Water Systems Council
221 North LaSalle'Street
Chicago, IL 60601
Price: $6.00
6. Environmental Engineering and Sanitation
Available from: Joseph A. Salvato
John Wiley & Sons, Inc.
Somerset, NJ 08873
Price: $55.00
7. National Interim Primary Drinking Water Regulations
Available from: Superintendent of Documents
U.S. Government Printing Office .
Washington, D.C. 20402
Stock No. 055-000-00157-0
Price: $5.50
8. Manual of Individual Water Supply Systems
Available from: Superintendent of Documents
U.S. Government Printing Office
Washington, DC 20402
Stock No. 055-000-00229-1
Price: $6.00
C-l
-------
SUGGESTED REFERENCES (CONTINUED)
9, "How to Conduct a Sanitary Survey" Procedures Manual
Available from: i New Mexico Health and Environmental Department
Environmental Improvement Division
P. 0. Box 968
Santa Fe, NM 87504-0968
Price: $4.00
10. "National Interim Primary Drinking Water Regulations"
Available from: Environmental Protection Agency
Office of Water Supply
Washington, D.C. 20460
EPA-570/9-76-003
11. "National Secondary Drinking Water Regulations"
Available from: Environmental Protection Agency
: Office of Water Supply
Washington, D.C. 20460
EPA-570/9-76-000
12. "The Safe Drinking Water Act Handbook for Water System Operators"
Available from: AWWA
6666 W. Quincy Avenue
Denver, Colorado 80235
13. "Introduction to Water Sources Transmission" Volume I
Available from: AWWA
6666 W. Quincy Avenue
Denver, Colorado 80235
14. "Introduction to Water Treatment" Volume II
Available from: ! AWWA
6666 W. Quincy Avenue
Denver, Colorado 80235
15. "Introduction to Water Distribution" Volume III
Available from: AWWA
6666 W. Quincy Avenue
Denver, Colorado 80235
16. "Introduction to Water Quality Analyses" Volume IV
Available from: AWWA
6666 W. Quincy Avenue
Denver, Colorado 80235
17. "Basic Science Concepts and Applications" Reference Handbook
Available from: AHWA
6666 W. Quincy Avenue
Denver, Colorado 80235
C-2
-------
SUGGESTED REFERENCES (CONTINUED)
18. "Manual of Water Utility Operations"
Available from: Texas Water Utilities Association
6521 Burnet La.
Austin, Texas 78757
19, "Manual of Instruction for Water Treatment Plant Operations"
Available from: Health Education Service
P. 0. Box 7283
Albany, New York 12224
20. "Planning for an Individual Water System"
Available from: American Association for Vocational Instructional
Materials
Engineering Center
Athens, Georgia 30602
ADDITIONAL READINGS
1. Water Treatment Plant Design, prepared jointly by the American Water Works
Association, Conference of State Sanitary Engineers, and American Society of
Civil Engineers
Available from: Data Processing Department, AWWA
6666 W. Quincy Avenue
Denver, CO 80235
Order NO. 10006
Price: To members - $14.40; nonmembers - $18.00
2. Water Quality and Treatment; A Handbook of Public Water Supplies;
American Hater Works Association, Third Edition, McGraw-Hill, 1971
Available from: Data Processing Department, AWWA
6666 W. Quincy Avenue
Denver, CO 80235
Order No. 10008
Price: To members - $34.10; nonmembers - $42.60
3- Manual of Treatment Techniques for Meeting the Interim Primary Drinking
Hater Regulation; EPA 600/8-77-005
Available from: ORD Publications
USEPA-CERI
26 West St. Clair Street
Cincinnati, OH 45268
Price: Free
C-3
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