96300592-Design-of-Sewerage-System.ppt

7/26/2019 96300592-Design-of-Sewerage-System.ppt

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BYBY

G. KRISHNANG. KRISHNAN

DESIGN OFDESIGN OFSEWERAGE SYSTEMSEWERAGE SYSTEM


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Sewage Mixture of water and waste produtsSewage Mixture of water and waste produts

T!pes of Sewage"T!pes of Sewage"

Do#esti sewage $ onsists of %i&uid wastes originatingDo#esti sewage $ onsists of %i&uid wastes originating

fro# urina%s' %atrines' (at)$roo#s' *it)en sin*s' was)fro# urina%s' %atrines' (at)$roo#s' *it)en sin*s' was)(asins et+ of t)e residentia%' o##eria% or institutiona%(asins et+ of t)e residentia%' o##eria% or institutiona%

(ui%dings+(ui%dings+

Industria% Sewage $ onsists of %i&uid wastes originatingIndustria% Sewage $ onsists of %i&uid wastes originating

fro# t)e industria% proesses of ,arious industries' su) asfro# t)e industria% proesses of ,arious industries' su) asd!eing' paper #a*ing' (rewing et+d!eing' paper #a*ing' (rewing et+

T)e su# of do#esti and industria% sewage' #a! (eT)e su# of do#esti and industria% sewage' #a! (e

ter#ed as sanitar! sewage or si#p%! sewageter#ed as sanitar! sewage or si#p%! sewage

Design of Sewerage S!ste#Design of Sewerage S!ste#


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SEWAGE -OM.OSITIONSEWAGE -OM.OSITION

/ i & u i d

0 0 + 1 t o 0 0 + 0 2

- a r ( o ) ! d r a t e

3 4 2

. r o t e i n s

5 4 2

F a t s

6 7 2

O r g a n i 1 7 28 d e r i, e d f r o # % i , i n g t ) i n g s 9

G r i t S a % t s M e t a % s

I n o r g a n i $ : 7 2

S o % i d s

7 + 6 t o 7 + : 2

M i r o $ o r g a n i s # s

i n # i % % i o n s

S E W A G E


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TY.I-A/ WASTE WATER SYSTEMTY.I-A/ WASTE WATER SYSTEM

Sewage Treatment

Plant

Disposal to water

bodiesRaw Sewage

pumping main

Raw Sewage

Collection System

Pumping

station

Reuse for

industrial

application


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Differene in t)e Design of water supp%! pipes and sewer pipes"Differene in t)e Design of water supp%! pipes and sewer pipes"

6+6+T)e water supp%! pipes arr! pure water wit)out ontaining an!T)e water supp%! pipes arr! pure water wit)out ontaining an!

*ind of so%id parti%es' eit)er organi or inorgani in nature+ T)e*ind of so%id parti%es' eit)er organi or inorgani in nature+ T)e

sewage' on t)e ot)er )and' does ontain su) parti%es insewage' on t)e ot)er )and' does ontain su) parti%es in

suspension and t)e )ea,ier of t)ese parti%es #a! sett%e down atsuspension and t)e )ea,ier of t)ese parti%es #a! sett%e down at

t)e (otto# of t)e sewers' as and w)en t)e f%ow ,e%oit! redues't)e (otto# of t)e sewers' as and w)en t)e f%ow ,e%oit! redues't)us u%ti#ate%! resu%ting in t)e %ogging of t)e sewers+t)us u%ti#ate%! resu%ting in t)e %ogging of t)e sewers+

3+3+T)e water supp%! pipes arr! water under pressure' and )eneT)e water supp%! pipes arr! water under pressure' and )ene

wit)in ertain %i#its' t)e! #a! (e arried up and down t)e )i%%swit)in ertain %i#its' t)e! #a! (e arried up and down t)e )i%%s

and t)e ,a%%e!s' w)ereas t)e sewer pipes arr! sewage asand t)e ,a%%e!s' w)ereas t)e sewer pipes arr! sewage as

gra,it! onduits and t)e! #ust t)erefore (e %aid at ontinuousgra,it! onduits and t)e! #ust t)erefore (e %aid at ontinuous

gradient in t)e downward diretion up to t)e outfa%% point' fro#gradient in t)e downward diretion up to t)e outfa%% point' fro#

w)ere it wi%% (e %ifted up' treated and disposed of+w)ere it wi%% (e %ifted up' treated and disposed of+

Design of Sewerage S!ste#Design of Sewerage S!ste#


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;!drau%is of Sewers

;!drau%is of Sewers

MANNINGS !RM"#A

< = > 86?n9 8R3?:S6?39@

W)ere S = ed s%ope of t)e sewer 86 in 6779

D = interna% dia#eter of sewer in ##

R = ;!drau%i #ean dept) in #

= Area ? wetted .eri#eter

< = ,e%oit! in #ps

n = ManningBs oeffiient of roug)ness


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Mannings -oeffiients 8n9Mannings -oeffiients 8n9

Fair interior surface

condition *

Sa%t g%aCed stoneware pipes 7+76

-e#ent onrete pipes 7+764

-ast iron pipes 7+76:

ri*' ung%aCed sewers?drains 7+764

As(estos e#ent 7+763

Plastic (smooth) pipes 7+766

Values of an full depth for.ipe Materia%S$No$

6

Good interior

surface condition

3

:

4

5 7+766

7+766

7+76:

7+763

7+76:

7+763


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Partially filled Circular Sewer SectionPartially filled Circular Sewer Section


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d%D &%' (%)

*$+ 6+777 6+777

+$, 6+63 6+755

+$- 6+67 7+05

+$. 6+637 7+:

+$/ 6+713 7+516

+$0 6+777 7+477

+$1 7+073 7+::1

+$2 7+115 7+605

+$3 7+564 7+7

+$* 7+76 7+736

;!drau%i E%e#ents of .artia% f%ow Sewers


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Design CriteriaDesign Criteria

Dia#eter of t)e sewers and t)e s%ope s)ou%d (e deidedDia#eter of t)e sewers and t)e s%ope s)ou%d (e deidedto #eet t)e fo%%owing onditionsto #eet t)e fo%%owing onditions Mini#u# siCe of t)e sewer s)ou%d (e not %ess t)an 647##+Mini#u# siCe of t)e sewer s)ou%d (e not %ess t)an 647##+ If an! future de,e%op#ent is antiipated (e!ond t)e )ead rea)'If an! future de,e%op#ent is antiipated (e!ond t)e )ead rea)'

t)e starting sewer an (e of 377## dia#eter+t)e starting sewer an (e of 377## dia#eter+ T)e ,e%oit! of f%ow and s%opes 8grade9 of sewers areT)e ,e%oit! of f%ow and s%opes 8grade9 of sewers are

,er! i#portant riteria in t)e sewer design+,er! i#portant riteria in t)e sewer design+ A se%f$%eansing ,e%oit! of 57#?s and 7#?s s)ou%dA se%f$%eansing ,e%oit! of 57#?s and 7#?s s)ou%d

(e #aintained at t)e present pea* f%ow' and at t)e(e #aintained at t)e present pea* f%ow' and at t)eu%ti#ate pea* f%ow respeti,e%!+u%ti#ate pea* f%ow respeti,e%!+

Sewer setion s)ou%d (e designed to run at partia% fu%%Sewer setion s)ou%d (e designed to run at partia% fu%%ondition a%wa!s not exeeding 7+7 fu%% dept) at t)eondition a%wa!s not exeeding 7+7 fu%% dept) at t)eu%ti#ate pea* f%ow+u%ti#ate pea* f%ow+


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S;A.ES OF SEWER .I.ESS;A.ES OF SEWER .I.ES

T)e sewer pipes are nor#a%%! iru%ar in setion' a%t)oug)T)e sewer pipes are nor#a%%! iru%ar in setion' a%t)oug)

so#e ot)er setions su) as (as*et )and%e s)ape' eggso#e ot)er setions su) as (as*et )and%e s)ape' eggs)ape' )orse s)oe s)ape' para(o%i s)ape' se#iiru%ars)ape' )orse s)oe s)ape' para(o%i s)ape' se#iiru%ars)ape' se#i e%%iptia% s)ape' retangu%ar s)ape et+s)ape' se#i e%%iptia% s)ape' retangu%ar s)ape et+


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FOR-ES A-TING ON SEWER .I.ESFOR-ES A-TING ON SEWER .I.ES

T)e strutura% design of t)e sewer pipes s)ou%d (e su)T)e strutura% design of t)e sewer pipes s)ou%d (e su)as to ena(%e t)e# to wit)stand t)e ,arious fores %i*e%! toas to ena(%e t)e# to wit)stand t)e ,arious fores %i*e%! too#e on t)e#+ T)e fo%%owing fores genera%%! o#e intoo#e on t)e#+ T)e fo%%owing fores genera%%! o#e intop%a! in t)e sewer pipes"p%a! in t)e sewer pipes"

6+6+Interna% pressure of sewageInterna% pressure of sewage

3+3+.ressure due to externa% %oads.ressure due to externa% %oads

:+:+Te#perature stressesTe#perature stresses

++F%exura% stresses+F%exura% stresses+


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SEWER MATERIA/SSEWER MATERIA/S


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MAN;O/ESMAN;O/ES

Man)o%es are #asonr! or R+-+-+ )a#(ers' onstruted atMan)o%es are #asonr! or R+-+-+ )a#(ers' onstruted at

suita(%e inter,a%s a%ong t)e sewer %ines' for pro,iding aesssuita(%e inter,a%s a%ong t)e sewer %ines' for pro,iding aess

into t)e#+into t)e#+

T)e #an)o%es' t)us )e%p in oining sewer %engt)s' and a%so )e%pT)e #an)o%es' t)us )e%p in oining sewer %engt)s' and a%so )e%p

in t)eir inspetion' %eaning and #aintenane+in t)eir inspetion' %eaning and #aintenane+

/oation and spaing of Man)o%es"/oation and spaing of Man)o%es"

T)e #an)o%es are genera%%! pro,ided at e,er! (end' untion'T)e #an)o%es are genera%%! pro,ided at e,er! (end' untion'

)ange of gradient' or )ange of sewer dia#eter+ n%ess t)ere)ange of gradient' or )ange of sewer dia#eter+ n%ess t)ere

are pratia% diffiu%ties' t)e sewer %ine (etween two #an)o%esare pratia% diffiu%ties' t)e sewer %ine (etween two #an)o%es

is %aid straig)t wit) e,en gradient+is %aid straig)t wit) e,en gradient+E,en w)en t)e sewer %ine runs straig)t' t)e #an)o%es areE,en w)en t)e sewer %ine runs straig)t' t)e #an)o%es are

pro,ided at regu%ar inter,a%s+pro,ided at regu%ar inter,a%s+

T)e spaing (etween t)e #an)o%es' in su) a ase' )owe,er'T)e spaing (etween t)e #an)o%es' in su) a ase' )owe,er'

depends #ain%! upon t)e siCe of t)e sewer %ine+depends #ain%! upon t)e siCe of t)e sewer %ine+


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T)e #an)o%e spaingHs' genera%%! adopted' on straig)tT)e #an)o%e spaingHs' genera%%! adopted' on straig)t

sewer rea)es' are gi,en (e%ow"sewer rea)es' are gi,en (e%ow"

Dia up to 7+: # 4 #

Dia up to 7+5 # 14 #

Dia up to 7+0 # 07 #

637 #

347 #

:77 #

Reo##ended SpaingHs of

Man)o%es on straig)t rea)es of

sewer %ines as per IS 613$6057

SiCe of t)e SewerS$No$

6

3

:

4

5

Dia up to 6+3 #

Dia up to 6+4 #

Dia greater t)an 6+4 #


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-/ASSIFI-ATION OF MAN;O/ES-/ASSIFI-ATION OF MAN;O/ES

Depending of t)eir dept)' t)e #an)o%es #a! (e %assified as"Depending of t)eir dept)' t)e #an)o%es #a! (e %assified as"

i+i+S)a%%ow #an)o%es is a(out 7+1 to 7+0 # in dept)' and isS)a%%ow #an)o%es is a(out 7+1 to 7+0 # in dept)' and is

onstruted at t)e start of a (ran) sewer or at p%aes' w)i)onstruted at t)e start of a (ran) sewer or at p%aes' w)i)

are not su(eted to )ea,! traffi+ Su) a #an)o%e is pro,idedare not su(eted to )ea,! traffi+ Su) a #an)o%e is pro,ided

wit) a %ig)t o,er at its top' and is a%%ed an inspetion )a#(er+wit) a %ig)t o,er at its top' and is a%%ed an inspetion )a#(er+

ii+ii+Nor#a% #an)o%es is a(out 6+4 # in dept) and is onstrutedNor#a% #an)o%es is a(out 6+4 # in dept) and is onstrutedeit)er s&uare 86# x 6#9 or retangu%ar 86+3# x 6#9 in rosseit)er s&uare 86# x 6#9 or retangu%ar 86+3# x 6#9 in ross

setion+ Its setion is not )anged wit) dept)' as its done in asetion+ Its setion is not )anged wit) dept)' as its done in a

deep #an)o%e+deep #an)o%e+

iii+iii+

Deep #an)o%es is )a,ing dept) #ore t)an 6+4#+ T)eDeep #an)o%es is )a,ing dept) #ore t)an 6+4#+ T)esetion of su) a #an)o%e is genera%%! not *ept t)e sa#e+ T)esetion of su) a #an)o%e is genera%%! not *ept t)e sa#e+ T)e

siCe in t)e upper portion is redued (! pro,iding an offset assiCe in t)e upper portion is redued (! pro,iding an offset as

s)own in t)e figure (e%ow+s)own in t)e figure (e%ow+


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ORDINARY MAN;O/EORDINARY MAN;O/E


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DEE. MAN;O/EDEE. MAN;O/E


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-IR-/AR DRO. MAN;O/E-IR-/AR DRO. MAN;O/E


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DESIGN OF SEWERAGE SYSTEMDESIGN OF SEWERAGE SYSTEM

Se%et sewage treat#ent and disposa% %oationSe%et sewage treat#ent and disposa% %oation

depending up on t)e a,ai%a(i%it! of %and or waterdepending up on t)e a,ai%a(i%it! of %and or waterourses'ourses'

Di,ide t)e town into nu#(er of ConesDi,ide t)e town into nu#(er of Cones'' Fators to (e onsidered in Coning"Fators to (e onsidered in Coning"

Special features such as railway line, NH, river etc., canSpecial features such as railway line, NH, river etc., canbe treated as zone boundaries since gravity sewerbe treated as zone boundaries since gravity sewercrossing of these features is expensive.crossing of these features is expensive.

An area of the town having a descending slope canAn area of the town having a descending slope canform a zoneform a zone

To restrict the depth of cutting to the predeterminedTo restrict the depth of cutting to the predeterminedlevel !" to #m$ since excavation under ground waterlevel !" to #m$ since excavation under ground watertable condition and % or in hard roc& is di'cult andtable condition and % or in hard roc& is di'cult andexpensive.expensive.

The site is available for the pumping station.The site is available for the pumping station. (xceeding the maximum depth of cutting for short(xceeding the maximum depth of cutting for short

lengths to avoid introduction of lift station is permitted.lengths to avoid introduction of lift station is permitted.


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Deide t)e %oation of t)e sewage pu#ping stationDeide t)e %oation of t)e sewage pu#ping station

8S.S9 for ea) of t)e Cones at t)e %owest e%e,ation8S.S9 for ea) of t)e Cones at t)e %owest e%e,ation

and a%so onsidering t)e site a,ai%a(%e+and a%so onsidering t)e site a,ai%a(%e+

S.S s)a%% )a,e fai%it! for pretreat#ent to re#o,eS.S s)a%% )a,e fai%it! for pretreat#ent to re#o,ef%oating %arge parti%es and grit a(out :7# x :7# %andf%oating %arge parti%es and grit a(out :7# x :7# %and

#a! (e re&uired+#a! (e re&uired+

W)en ade&uate extent of %and is not a,ai%a(%e %iftW)en ade&uate extent of %and is not a,ai%a(%e %ift

station an (e pro,ided instead of S.S+station an (e pro,ided instead of S.S+

/ift station is a s#a%% pu#ping station wit)out fai%it!/ift station is a s#a%% pu#ping station wit)out fai%it!

for pretreat#entfor pretreat#ent


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Main pu#ping station 8M.S9 is %oated nearer to t)e ST.Main pu#ping station 8M.S9 is %oated nearer to t)e ST.site+ M.S wi%% o%%et sewage fro# a%% Cones and pu#p tosite+ M.S wi%% o%%et sewage fro# a%% Cones and pu#p toST.ST.

S.S of one of t)e Cones nearer to ST. #a! (e on,ertedS.S of one of t)e Cones nearer to ST. #a! (e on,ertedas M.Sas M.S

.repare a #ap of sewer networ* (! a%igning t)e sewer.repare a #ap of sewer networ* (! a%igning t)e sewer%ines in roads a%ong t)e natura% s%ope of t)e terrain to%ines in roads a%ong t)e natura% s%ope of t)e terrain todrain into t)e o%%etion we%%'drain into t)e o%%etion we%%'

DonBt a%ign sewers against t)e s%ope and aross t)eDonBt a%ign sewers against t)e s%ope and aross t)e

ridgesridges In exeptiona% ase' a%igning aross a s#a%% ridge isIn exeptiona% ase' a%igning aross a s#a%% ridge is

per#ittedper#itted


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DESIGN OF SEWERAGE SYSTEMDESIGN OF SEWERAGE SYSTEM- contd- contd

Ade&uate nu#(er of Man)o%es are neessar! to fai%itateAde&uate nu#(er of Man)o%es are neessar! to fai%itate

%eaning%eaning Maxi#u# spaing for s#a%% dia#eter sewers"Maxi#u# spaing for s#a%% dia#eter sewers" :7#:7#

Maxi#u# spaing for %arger dia#eter sewers"Maxi#u# spaing for %arger dia#eter sewers" 57# to 677#57# to 677#

Mar* t)e positions of t)e #an)o%es in t)e sewer %a!outMar* t)e positions of t)e #an)o%es in t)e sewer %a!out

#ap+#ap+ Assess t)eAssess t)e nu#(er of antiipated ;S-snu#(er of antiipated ;S-s Ensure at %east Ensure at %east

472 of t)e properties wi%% )a,e onnetions472 of t)e properties wi%% )a,e onnetions

Assu#e orretAssu#e orret .ea* Fator.ea* Fator8(ased on t)e ontri(uting8(ased on t)e ontri(uting

popu%ation to t)e setion under onsideration9 to assesspopu%ation to t)e setion under onsideration9 to assess.ea* F%ow.ea* F%ow++ .ea* fator of : is prefera(%e for a%% setions+.ea* fator of : is prefera(%e for a%% setions+

Sewers are designed as a gra,it! s!ste# forSewers are designed as a gra,it! s!ste# for partia% f%owpartia% f%ow

onditiononditionon%!on%!


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DESIGN OF SEWERAGE SYSTEMDESIGN OF SEWERAGE SYSTEM$-ontd+$-ontd+

-onsider su(soi% ondition and %e,e% of ground water-onsider su(soi% ondition and %e,e% of ground water

ta(%e and fix t)e #axi#u# dept) of utting' w)i) #a!ta(%e and fix t)e #axi#u# dept) of utting' w)i) #a!(e 4 to 5#'(e 4 to 5#'

For t)e assu#ed Coning' (! roug) a%u%ationFor t)e assu#ed Coning' (! roug) a%u%ationonsidering t)e #axi#u# %engt) of t)e Cone andonsidering t)e #axi#u# %engt) of t)e Cone and

assu#ing a grade of 6 in 377 a%u%ate t)e dept) ofassu#ing a grade of 6 in 377 a%u%ate t)e dept) ofexa,ation and )e* wit) t)e #axi#u# dept) ofexa,ation and )e* wit) t)e #axi#u# dept) ofuttingutting

If t)e a%u%ated dept) is wit)in t)e per#issi(%e dept) ofIf t)e a%u%ated dept) is wit)in t)e per#issi(%e dept) ofexa,ation proeed furt)er for t)e detai%ed designing ofexa,ation proeed furt)er for t)e detai%ed designing of

sewers adopting t)e Coning+sewers adopting t)e Coning+ If t)e a%u%ated dept) of utting exeeds t)eIf t)e a%u%ated dept) of utting exeeds t)e

per#issi(%e utting' re,ise t)e Coning of t)e town' (!per#issi(%e utting' re,ise t)e Coning of t)e town' (!s)ifting t)e %oation of pu#ping station or introduings)ifting t)e %oation of pu#ping station or introduingadditiona% pu#ping station?%ift stations+additiona% pu#ping station?%ift stations+


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/ift stations/ift stations

/ift stations are re&uired to e%e,ate and transport sewage in/ift stations are re&uired to e%e,ate and transport sewage in

sewerage s!ste#s w)en ontinuation of gra,it! f%ow is no %ongersewerage s!ste#s w)en ontinuation of gra,it! f%ow is no %ongerfeasi(%e+feasi(%e+ In f%at terrain' area %ose to seas)ore' sewers enroute to aIn f%at terrain' area %ose to seas)ore' sewers enroute to a

pu#ping?treat#ent p%ant #a! inrease in dept) to t)e point w)erepu#ping?treat#ent p%ant #a! inrease in dept) to t)e point w)ereit is i#pratia% to ontinue gra,it! f%ow eono#ia%%! (eause ofit is i#pratia% to ontinue gra,it! f%ow eono#ia%%! (eause oft)e )ig) ost of exa,ation+t)e )ig) ost of exa,ation+

;ere' a %ift station an (e insta%%ed to %ift t)e sewage to t)e e%%$;ere' a %ift station an (e insta%%ed to %ift t)e sewage to t)e e%%$#out) )a#(er in a sewer at a )ig)er %e,e%#out) )a#(er in a sewer at a )ig)er %e,e%

/ift station is an en%arged siCe M; fitted wit) su(#ersi(%e pu#p/ift station is an en%arged siCe M; fitted wit) su(#ersi(%e pu#pwit) f%oat ontro% operationwit) f%oat ontro% operation

.ro,ide Su(#ersi(%e non$%ogging pu#p of 3 3+4 DWF 83Nos+' 6.ro,ide Su(#ersi(%e non$%ogging pu#p of 3 3+4 DWF 83Nos+' 6

No+ stand (!9No+ stand (!9 /ift station #a! (e adopted w)en t)e design pea* f%ow is %ess t)an/ift station #a! (e adopted w)en t)e design pea* f%ow is %ess t)an

6777 %p#6777 %p# O,erf%ow arrange#ent fro# t)e %ift station to t)e near(! drain isO,erf%ow arrange#ent fro# t)e %ift station to t)e near(! drain is

neessar! to a,oid sur)arging of sewersneessar! to a,oid sur)arging of sewers


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/IFT STATIONS


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DESIGN OF SEWERAGE SYSTEMDESIGN OF SEWERAGE SYSTEM$-ontd+$-ontd+

SuffiientSuffiient gradesgradess)ou%d (e adopted to #aintain as)ou%d (e adopted to #aintain a

#ini#u# se%f$%eansing ,e%oit!#ini#u# se%f$%eansing ,e%oit! 7+5#ps for t)e present pea* f%ow7+5#ps for t)e present pea* f%ow

7+#ps for t)e u%ti#ate pea* f%ow7+#ps for t)e u%ti#ate pea* f%ow

Mini#u# dept) of uttingMini#u# dept) of utting 77## to 6777##77## to 6777## Mini#u# Mini#u#dept) is fixed in su) a wa! to )a,e t)e )ouse sewer is safe%!dept) is fixed in su) a wa! to )a,e t)e )ouse sewer is safe%!

onneted to t)e street sewer+ Mini#u# dept) s)ou%d a%so pro,ideonneted to t)e street sewer+ Mini#u# dept) s)ou%d a%so pro,ide

neessar! o,er to t)e sewer to protet it fro# %oad fro# t)e traffineessar! o,er to t)e sewer to protet it fro# %oad fro# t)e traffi

Maxi#u# dept) of uttingMaxi#u# dept) of utting 4+7 to 5+7#4+7 to 5+7#depending up ondepending up onwater ta(%e ondition and t!pe of su(stratawater ta(%e ondition and t!pe of su(strata

se ManningBs for#u%a for o#puting ,e%oit! and f%owse ManningBs for#u%a for o#puting ,e%oit! and f%ow

in t)e setionin t)e setion


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Steps in the design of Sewerage systemSteps in the design of Sewerage system Review the performance of the existing sewerage systems inReview the performance of the existing sewerage systems in

operationoperation Insufficient flow due to lack of connections leading to silting andInsufficient flow due to lack of connections leading to silting and

clogging in sewersclogging in sewers Flow of sewage in the open drains even after installation ofFlow of sewage in the open drains even after installation of

sewerage system and fail to protect the environment (land andsewerage system and fail to protect the environment (land andwater) from pollution and make them for eneficial useswater) from pollution and make them for eneficial uses

Inade!uate "#$ of S%P (&ven simple maintenance of 'SP is notInade!uate "#$ of S%P (&ven simple maintenance of 'SP is notcarried out properly)carried out properly)

Study the various options availale with reference to capital andStudy the various options availale with reference to capital and"#$ cost"#$ cost

Collection systemsCollection systems*Conventional sewerage system*Conventional sewerage system+*Small ore sewerage system+*Small ore sewerage system Sewage treatmentSewage treatment*Conventional methods*Conventional methods

+* ,ow-cost methods +* ,ow-cost methods Select .ppropriate collection system and Sewage treatment methodSelect .ppropriate collection system and Sewage treatment method


32/51

Steps in t)e design of Sewerage networ*Steps in t)e design of Sewerage networ*

T)e sewage generated fro# an area is o%%eted t)roug)T)e sewage generated fro# an area is o%%eted t)roug)a sewer networ* onsists of sewers and on,e!ed to t)ea sewer networ* onsists of sewers and on,e!ed to t)esewage pu#ping station for onward on,e!ane to t)esewage pu#ping station for onward on,e!ane to t)esewage treat#ent p%ant for furt)er treat#ent andsewage treat#ent p%ant for furt)er treat#ent and

disposa%+disposa%+ T)e sewer networ* is for#u%ated wit) t)e )e%p ofT)e sewer networ* is for#u%ated wit) t)e )e%p of

ontours+ Genera%%!' t)e sewage pu#ping station 8S.S9 isontours+ Genera%%!' t)e sewage pu#ping station 8S.S9 is%oated at %ow$%!ing area of t)e at)#ents+%oated at %ow$%!ing area of t)e at)#ents+

In addition to t)e ontour %e,e%s' t)e distane of t)eIn addition to t)e ontour %e,e%s' t)e distane of t)e

fart)est point of t)e networ* fro# t)e S.S is a%so ta*enfart)est point of t)e networ* fro# t)e S.S is a%so ta*eninto onsideration w)i%e deiding t)e nu#(er of su($into onsideration w)i%e deiding t)e nu#(er of su($at)#ent areas or Cones of t)e sewage o%%etionat)#ent areas or Cones of t)e sewage o%%etions!ste#+s!ste#+


33/51


After formulation of the zones with networks,After formulation of the zones with networks,manholes are marked at eer! "# metres a$artmanholes are marked at eer! "# metres a$artfrom %un&tions and &han'e in dire&tions.from %un&tions and &han'e in dire&tions.

(he network &onsists of trunk sewer, main sewer,(he network &onsists of trunk sewer, main sewer,

su)main, )ran&h, su)*)ran&h and laterals et&.su)main, )ran&h, su)*)ran&h and laterals et&.and the line num)ers were 'ien a&&ordin'l!.and the line num)ers were 'ien a&&ordin'l!.

+anhole num)ers are assi'ned )ased on the line+anhole num)ers are assi'ned )ased on the linenum)er.num)er.

(he nomen&latures of manhole num)ers are(he nomen&latures of manhole num)ers are'enerall! as $er the 'uidelines s$e&ied )!'enerall! as $er the 'uidelines s$e&ied )!-entral u)li& Health / 0nironmental-entral u)li& Health / 0nironmental0n'ineerin' 1r'anisation 2-H0013 +anual.0n'ineerin' 1r'anisation 2-H0013 +anual.


34/51


(he Sewer s!stem has )een desi'ned )! formin'(he Sewer s!stem has )een desi'ned )! formin'se'ments &om$risin' of "*4 manholes.se'ments &om$risin' of "*4 manholes.

A &ontri)utor! area is assi'ned to ea&h se'mentA &ontri)utor! area is assi'ned to ea&h se'mentde$endin' on arious t!$es of land use in thede$endin' on arious t!$es of land use in the

se'ment.se'ment. (he &ontri)utin' area for the se'ment is then(he &ontri)utin' area for the se'ment is then

&onerted to an 05uialent Residential Area 20RA3.&onerted to an 05uialent Residential Area 20RA3. (he ward densit! is a$$lied while &al&ulatin'(he ward densit! is a$$lied while &al&ulatin'

se'ment*wise $o$ulation )ased on &ontri)utin'se'ment*wise $o$ulation )ased on &ontri)utin'

0RA.0RA. (his e6er&ise is re$eated for whole network to(his e6er&ise is re$eated for whole network to

arrie se'ment * wise $o$ulation.arrie se'ment * wise $o$ulation.


35/51


-ontri(utor! area of a seg#ent of a stret) of 677 #-ontri(utor! area of a seg#ent of a stret) of 677 #

%engt) of sewer is a%u%ated+ T)is area is t)en on,erted%engt) of sewer is a%u%ated+ T)is area is t)en on,ertedinto E&ui,a%ent Residentia% Area 8ERA9 (! app%!inginto E&ui,a%ent Residentia% Area 8ERA9 (! app%!ingsuita(%e fators to ,arious %and uses as indiated (e%ow"suita(%e fators to ,arious %and uses as indiated (e%ow" Residentia% Area 8RA9Residentia% Area 8RA9 == 6+76+7 Institutiona%Institutiona% == 7+347+34

-o##eria% Area-o##eria% Area == 7+347+34 Industria%Industria% == 7+67+6 T)e tota% ERA t)erefore is a%u%ated as"T)e tota% ERA t)erefore is a%u%ated as"

ERA =ERA = 6+7 x Residentia% area J 7+34 x Institutiona% area J 7+34 x6+7 x Residentia% area J 7+34 x Institutiona% area J 7+34 x-o##eria% area J 7+6 x Industria% area-o##eria% area J 7+6 x Industria% area

Mu%tip%!ing ERA (! popu%ation densit! of t)eMu%tip%!ing ERA (! popu%ation densit! of t)eorresponding ward gi,es t)e nu#(er of persons in t)atorresponding ward gi,es t)e nu#(er of persons in t)atontri(uting area+ontri(uting area+

A return of 72 of t)e rate of water supp%! is treated asA return of 72 of t)e rate of water supp%! is treated aswaste water generation fro# ea) indi,idua%+waste water generation fro# ea) indi,idua%+

Furt)er' infi%tration of ground water into t)e s!ste# is a%soFurt)er' infi%tration of ground water into t)e s!ste# is a%soonsidered+onsidered+


36/51

Design Approa)Design Approa)$-ontd+$-ontd+

-onsider su(soi% ondition and %e,e% of ground water ta(%e-onsider su(soi% ondition and %e,e% of ground water ta(%e

and fix t)e #axi#u# dept) of utting' w)i) #a! (e 4 toand fix t)e #axi#u# dept) of utting' w)i) #a! (e 4 to5#'5#'

For t)e assu#ed Coning' #ar* t)e trun* sewer a%ign#entFor t)e assu#ed Coning' #ar* t)e trun* sewer a%ign#ent ! roug) a%u%ation assu#ing an a,erage grade of 6 in! roug) a%u%ation assu#ing an a,erage grade of 6 in

377 a%u%ate t)e dept) of exa,ation and )e* wit) t)e377 a%u%ate t)e dept) of exa,ation and )e* wit) t)e#axi#u# dept) of utting#axi#u# dept) of utting

If t)e a%u%ated dept) is wit)in t)e per#issi(%e dept) ofIf t)e a%u%ated dept) is wit)in t)e per#issi(%e dept) ofexa,ation proeed furt)er for t)e detai%ed designing of t)eexa,ation proeed furt)er for t)e detai%ed designing of t)eo%%etion s!ste# adopting t)e Coning+o%%etion s!ste# adopting t)e Coning+

If t)e a%u%ated dept) of utting exeeds t)e per#issi(%eIf t)e a%u%ated dept) of utting exeeds t)e per#issi(%eutting' re,ise t)e Coning of t)e town' (! s)ifting t)eutting' re,ise t)e Coning of t)e town' (! s)ifting t)e%oation of pu#ping station or introduing additiona%%oation of pu#ping station or introduing additiona%pu#ping station?%ift stations+pu#ping station?%ift stations+

Mar* t)e positions of t)e #an)o%es in t)e sewer networ*Mar* t)e positions of t)e #an)o%es in t)e sewer networ*#ap+#ap+

N b i f M 4 l d SN b i

f M 4 l d S


37/51

Numbering of Man4oles and SewersNumbering of Man4oles and Sewers

+anholes are 'enerall! num)ered+anholes are 'enerall! num)ered

from the $um$in' station endfrom the $um$in' station end)a&kwards alon' the +ain sewer.)a&kwards alon' the +ain sewer.

Num)erin' of manholes andNum)erin' of manholes and

sewers &an )e done in man!sewers &an )e done in man!

wa!s.wa!s.

(he sewer shall )e desi'nated )!(he sewer shall )e desi'nated )!the manhole to whi&h it %oins.the manhole to whi&h it %oins.

Num)erin' manholes is furnishedNum)erin' manholes is furnished

in 7i'.in 7i'.

In &ase of desi'n of sewerIn &ase of desi'n of sewer

network usin' &om$uternetwork usin' &om$uter

$ro'ramme, manholes are$ro'ramme, manholes are

&onsidered as nodes.&onsidered as nodes.

Node num)ers are assi'ned inNode num)ers are assi'ned in

an! se5uen&e and the sewer isan! se5uen&e and the sewer is

desi'nated as a link withdesi'nated as a link with

&onne&tin' node num)ers.&onne&tin' node num)ers.


38/51

G+/+ K Man ;o%es

6 03+64#

3 03+:4#

: 03+47#

03+7#

4 03+07#

5 0:+67#

1 0:+37#

0:+37#

0 0:+54#

:A 03+57#

: 03+54#

A 03+07#

0:+74#

- 0:+67#

1A 0:+57#

1 0:+ 54#

S565R N5T6!R7 AND DATA


39/51

;YDRA/I- -A/-/ATION TA/E OF SEWER NETWORL

Se&tion8IN0N1

-umulatieo$ulation

Sewera'eGeneration2ltr9

se&3

7ull Boredis&har'e :#4#

;ia 2mm3Slo$e< in2+tr3

Slo$e8en't

h

=f frommannin'sformula

>7 2l$s3

>9>f d9;f 9=f 2m9s3 >9>f d9;f 9=f 2m9s3GR1?N;

80=08 2m3

IN=0R( 80=082m3

0;R-

Start 0nd :#


40/51

PR"/,&$S I0 %1& S&'&RSPR"/,&$S I0 %1& S&'&RS

T)e sett%e(%e so%ids are %i*e%! to sett%e in t)e sewer w)enT)e sett%e(%e so%ids are %i*e%! to sett%e in t)e sewer w)en

t)e f%ow is ,er! %ess and t)e ,e%oit! is %ess t)an se%ft)e f%ow is ,er! %ess and t)e ,e%oit! is %ess t)an se%f

%eaning ,e%oit!+%eaning ,e%oit!+

Sett%ed so%ids s)ou%d (e f%us)ed at %east one in a da! (!Sett%ed so%ids s)ou%d (e f%us)ed at %east one in a da! (!#aintaining se%f %eansing ,e%oit!#aintaining se%f %eansing ,e%oit!

Se%f %eansing ,e%oit! ou%d (e a)ie,ed on%! during t)eSe%f %eansing ,e%oit! ou%d (e a)ie,ed on%! during t)e

pea* f%ow+pea* f%ow+

If se%f %eansing ,e%oit! is not a)ie,ed in an! setion ofIf se%f %eansing ,e%oit! is not a)ie,ed in an! setion oft)e sewers e,en wit) pea* f%ow' artifiia%%! se%f %eansingt)e sewers e,en wit) pea* f%ow' artifiia%%! se%f %eansing

,e%oit! s)ou%d (e a)ie,ed (! f%us)ing,e%oit! s)ou%d (e a)ie,ed (! f%us)ing


41/51

%2PIC., S&'.3& P4$PI03 S%.%I"0%2PIC., S&'.3& P4$PI03 S%.%I"0


42/51

%2PIC., S&'.3& P4$PI03 S%.%I"0%2PIC., S&'.3& P4$PI03 S%.%I"0


43/51


44/51

Survey and InvestigationSurvey and Investigation

Sur,e! and in,estigation are pre$re&uisites (ot) forSur,e! and in,estigation are pre$re&uisites (ot) forfra#ing t)e feasi(i%it! report and t)e preparation offra#ing t)e feasi(i%it! report and t)e preparation ofsewerage proetsewerage proet

T)e engineering designs are dependent on t)eT)e engineering designs are dependent on t)eorretness of t)e data o%%eted and its properorretness of t)e data o%%eted and its proper

e,a%uatione,a%uation T)e sur,e! for data o%%etion in%udes t)e fo%%owing twoT)e sur,e! for data o%%etion in%udes t)e fo%%owing twostepssteps -o%%etion of (asi infor#ation-o%%etion of (asi infor#ation .roet sur,e!s.roet sur,e!s

asi infor#ation s)ou%d (e o%%eted on t)e fo%%owingaspets .)!sia% Aspets.)!sia% Aspets De,e%op#ent AspetsDe,e%op#ent Aspets Ot)er AspetsOt)er Aspets


45/51

Physical .spectsPhysical .spects

Topograp)! or e%e,ation differene of t)e town and t)eTopograp)! or e%e,ation differene of t)e town and t)eadoining area for deiding %oation of disposa% wor*sadoining area for deiding %oation of disposa% wor*s

Su(soi% onditions' dept) of groundwater ta(%e and itsSu(soi% onditions' dept) of groundwater ta(%e and itsf%utuations+f%utuations+

In t)e a(sene of an! reords' pre%i#inar! data s)ou%d (eIn t)e a(sene of an! reords' pre%i#inar! data s)ou%d (eo%%eted (! putting at %east : tria% (ores or tria% pits pero%%eted (! putting at %east : tria% (ores or tria% pits per)etare)etare

nderground fai%ities %i*e stor# water drains' )ousenderground fai%ities %i*e stor# water drains' )ouseser,ie onnetions of water supp%!?drainage' e%etria%ser,ie onnetions of water supp%!?drainage' e%etria%and te%ep)one a(%es' andand te%ep)one a(%es' and

/oation of streets and adoining areas %i*e%! to (e #erged/oation of streets and adoining areas %i*e%! to (e #erged .ossi(%e soures of infor#ation are".ossi(%e soures of infor#ation are"

Existing #aps and p%ans fro# re,enue or town sur,e!s or Sur,e!Existing #aps and p%ans fro# re,enue or town sur,e!s or Sur,e!of Indiaof India

Topograp)ia% #ap of sur,e! of IndiaTopograp)ia% #ap of sur,e! of India Aeria% p)otograp)sAeria% p)otograp)s Existing instru#enta% sur,e!s (! Muniipa%itiesExisting instru#enta% sur,e!s (! Muniipa%ities


46/51

5evelopment .spects5evelopment .spects T!pe of %and use su) as o##eria%' industria%' residentia%T!pe of %and use su) as o##eria%' industria%' residentia%

and rereationa%and rereationa% -ensus popu%ation' densit! of popu%ation' trends of-ensus popu%ation' densit! of popu%ation' trends of

popu%ation growt)popu%ation growt) T!pes and nu#(er of industries and %oation of t)eirT!pes and nu#(er of industries and %oation of t)eir

wastewater dis)arge pointswastewater dis)arge points Rainfa%% detai%sRainfa%% detai%s Detai%s of existing drainage and sewerage fai%itiesDetai%s of existing drainage and sewerage fai%ities asis of design and infor#ation on t)e #aintenane of t)easis of design and infor#ation on t)e #aintenane of t)e

existing sewerage s!ste# if a,ai%a(%e eff%uent disposa% sitesexisting sewerage s!ste# if a,ai%a(%e eff%uent disposa% sites

and t)eir onditionsand t)eir onditions .ossi(%e soures of infor#ation.ossi(%e soures of infor#ation

-ensus reords-ensus reords Town and #etropo%itan Master p%ans and /and use p%ansTown and #etropo%itan Master p%ans and /and use p%ans Meteoro%ogia% dataMeteoro%ogia% data

.o%%ution -ontro% oard.o%%ution -ontro% oard


47/51

"ther .spects"ther .spects

-)anges in po%itia% (oundaries (! #erger of adaent-)anges in po%itia% (oundaries (! #erger of adaent

o##unitieso##unities Feasi(i%it! of #u%ti$#uniipa% s!ste#sFeasi(i%it! of #u%ti$#uniipa% s!ste#s

.re,ai%ing water po%%ution pre,ention regu%ations' and.re,ai%ing water po%%ution pre,ention regu%ations' and

ot)er ru%es re%ating to dis)arge of industria% and do#estiot)er ru%es re%ating to dis)arge of industria% and do#esti

wasteswastes .resent status of t)e go,ern#ent or #uniipa% aut)orit!.resent status of t)e go,ern#ent or #uniipa% aut)orit!

sponsoring t)e proet' its apait!' and ade&ua! tosponsoring t)e proet' its apait!' and ade&ua! to

satisfatori%! i#p%e#ent and #aintain t)e proetsatisfatori%! i#p%e#ent and #aintain t)e proet

T)e i#pats %i*e%! to (e aused to t)e o##unit! duringT)e i#pats %i*e%! to (e aused to t)e o##unit! duringexeution and feasi(i%it! of #ini#iCing t)e#exeution and feasi(i%it! of #ini#iCing t)e#

.ossi(%e soures of infor#ation.ossi(%e soures of infor#ation Nationa% AtsNationa% Ats

State and Muniipa% /aws and !e%awsState and Muniipa% /aws and !e%aws


48/51

Pro6ect SurveysPro6ect Surveys .re%i#inar! .roet Sur,e!s.re%i#inar! .roet Sur,e!s

-o%%et data on apait! re&uired' (asi arrange#ent and siCe'-o%%et data on apait! re&uired' (asi arrange#ent and siCe'p)!sia% features affeting genera% %a!outp)!sia% features affeting genera% %a!out

Data on ost and t)e esa%ation of pries of (asi #ateria%s andData on ost and t)e esa%ation of pries of (asi #ateria%s and#et)ods of finaning#et)ods of finaning

A%% t)e (asi data o(tained #ust (e re%ia(%e (ut need not (e inA%% t)e (asi data o(tained #ust (e re%ia(%e (ut need not (e inpreise and detai%preise and detai%

Detai%ed .roet Sur,e!sDetai%ed .roet Sur,e!s T)ese sur,e!s for# t)e (asis for t)e engineering design as we%% asT)ese sur,e!s for# t)e (asis for t)e engineering design as we%% as

for t)e preparation of p%ans and speifiationsfor t)e preparation of p%ans and speifiations Must (e preise and ontains ontours of a%% areas to (e ser,edMust (e preise and ontains ontours of a%% areas to (e ser,ed

wit) a%% detai%s t)at wi%% fai%itate t)e designerwit) a%% detai%s t)at wi%% fai%itate t)e designer

In%ude networ* of (en) #ar*s and tra,erse sur,e!s to identif!In%ude networ* of (en) #ar*s and tra,erse sur,e!s to identif!t)e nature and extent of t)e existing underground struturest)e nature and extent of t)e existing underground strutures

-onstrution Sur,e!s-onstrution Sur,e!s Esta(%is) a%% ontro% points su) as (ase %ines and (en) #ar*s forEsta(%is) a%% ontro% points su) as (ase %ines and (en) #ar*s for

sewer a%ign#ent and grade wit) referene to per#anent o(etssewer a%ign#ent and grade wit) referene to per#anent o(ets


49/51

Data to be collected in a detailed sur&eyData to be collected in a detailed sur&ey

T)e %a!out p%an of t)e town wit) ontours s)owing t)eT)e %a!out p%an of t)e town wit) ontours s)owing t)eroads and drainage ourses'roads and drainage ourses'

T)e #uniipa% #ap s)owing ward (oundariesT)e #uniipa% #ap s)owing ward (oundaries /e,e%s a%ong t)e road at inter,a% of 67#+/e,e%s a%ong t)e road at inter,a% of 67#+

T)e %e,e%s at street untions' %owest p%int) %e,e% of t)eT)e %e,e%s at street untions' %owest p%int) %e,e% of t)e(ui%ding and t)e su%%age out%et(ui%ding and t)e su%%age out%et T)e widt) of t)e street and t)e road for#edT)e widt) of t)e street and t)e road for#ed T)e %oation and extent of ,aant #uniipa% sitesT)e %oation and extent of ,aant #uniipa% sites

a,ai%a(%e wit)in t)e town as we%% as on t)e perip)er! ofa,ai%a(%e wit)in t)e town as we%% as on t)e perip)er! of

t)e town for %oating pu#ping station and ST.+t)e town for %oating pu#ping station and ST.+ T)e a,ai%a(i%it! of Re,enue pora#(o*e %and on t)eT)e a,ai%a(i%it! of Re,enue pora#(o*e %and on t)e

outs*irt of t)e town and?or dr! %ands at reasona(%e ostouts*irt of t)e town and?or dr! %ands at reasona(%e ostfor %oating t)e treat#ent p%ant and disposa% wor*s'for %oating t)e treat#ent p%ant and disposa% wor*s'


50/51

Data to be collected in a detailed sur&eyData to be collected in a detailed sur&ey8Contd8Contd

T)e )!dro%og! of water ourses if an!' wit) detai%s ofT)e )!dro%og! of water ourses if an!' wit) detai%s of#ini#u# f%ow and #axi#u# water %e,e%#ini#u# f%ow and #axi#u# water %e,e%

T)e %e,e% of groundwater ta(%e in su##er and winterT)e %e,e% of groundwater ta(%e in su##er and winterand su(soi% onditions' o%%eted fro# t)e existing openand su(soi% onditions' o%%eted fro# t)e existing open

we%%s'we%%s' T)e su(soi% partiu%ars a%ong t)e a%ign#ent of t)eT)e su(soi% partiu%ars a%ong t)e a%ign#ent of t)e

sewers (! putting tria% pits and tria% (oressewers (! putting tria% pits and tria% (ores'' .opu%ation of t)e town as per t)e %atest ensus and.opu%ation of t)e town as per t)e %atest ensus and

present popu%ation'present popu%ation' Future popu%ation esti#ated (ased on ot)er proetsFuture popu%ation esti#ated (ased on ot)er proets

su) as water supp%! proet or (! foreast #et)od'su) as water supp%! proet or (! foreast #et)od'


51/51

Data to be collected in a detailed sur&eyData to be collected in a detailed sur&ey8Contd8Contd

T)e detai%s of existing water supp%! and proposedT)e detai%s of existing water supp%! and proposedwater supp%! i#pro,e#ents proets if an!+water supp%! i#pro,e#ents proets if an!+

E%e,ations of t)e si%%s of (ui%ding and t)e dept) atE%e,ations of t)e si%%s of (ui%ding and t)e dept) atw)i) t)e )ouse drainage is existingw)i) t)e )ouse drainage is existing

-)arater' age and ondition of t)e pa,e#ent of-)arater' age and ondition of t)e pa,e#ent ofstreet?roadstreet?road

T)e detai%s of underground fai%ities %i*e a(%es ofT)e detai%s of underground fai%ities %i*e a(%es ofte%ep)one and e%etriit!te%ep)one and e%etriit!

W)en good infor#ation is %a*ing' it #a! (e ad,isa(%eW)en good infor#ation is %a*ing' it #a! (e ad,isa(%eto )a,e pits exa,ated in streets to o(tain t)e re&uireto )a,e pits exa,ated in streets to o(tain t)e re&uiredata+data+

Documents

96300592-Design-of-Sewerage-System.ppt