SANJEEB MOHAPATRAM Tech Environmental Engineering

Project TraineeNational Environmental Engineering Research

Institute, Nagpur

S.R. Watpade Deputy Engineer

NMC, Nagpur

Sridevi H.Assistant professor

M IT, Manipal, Karnataka 1

Dr. A P SargaonkarPrincipal Scientist

ESDM, NEERI, Nagpur

Dr. P K LabhasetwarPrincipal Scientist,

WTM, NEERI, Nagpur

Swapnil KambleProject Assistant

ESDM, NEERI, Nagpur

Session 2: Urban Water Supply

Outline

• Introduction• Objective• Literature Review• Methodology• Result & Discussion• Conclusion• References

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Introduction• Water Distribution System

– Raw water source, Treatment Plant, Pumping Station, Reservoir/Tank– Pipe/Distribution Network

• Hydraulic Integrity– Hydraulics– Water Quality

• Problems– Developed vs Developing countries– Intermittent supply

• EPANET Capability– Hydraulics– Water Quality– Limitation

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Objective

Performance evaluation of the pilot water distribution system for:- Intermittent Analysis- Diurnal Analysis

Literature Review

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Hydraulics of Intermittent Supply

• Specific problems include (Halcrow Water Services and Bristol Water Services, 2003; Tiwari,2012):

– Serious risk to public health– Inability to practice effective supply management; – Inability to practice effective demand management; – Operational inadequacies, which unduly weaken the physical infrastructure; – Customer inconvenience.

• W.r.t Time• W.r.t Quantity

• “Charging” process in pipes

• This is a short period (first 20-30 minutes)

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Where: Hi: Pressure at a node i Hmin: Minimum required pressure at a node i Hmax: Maximum pressure at a node iQi: Demand at a node i Qmax: User specified (requested) demand at a node i

Pressure dependent demands (Vairavamoorthy,2008 Buchberger,2008)

Household Reservoir(http://sdteffen.de/diplom/web/node11_ct.html) •Each demand node is represented by artificial reservoir (Buchberger,2008).•Infinite sink

•Total head = Elevation + Pressure Head (1 meter)

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Equivalent Pipe DiameterThe individual reservoir fill rates depend mainly on the headloss over the pipeline that connects the tank to the network. (Bansal,1989;Buchberger,2008; Walski, 2003).

Where

=Diameter of equivalent pipe=Length of equivalent pipe

=Roughness of equivalent pipe=Diameter of individual pipe

=Length of individual pipe=Roughness of individual pipe

Fractal Theory and Diurnal Pattern •Hourly Water Consumption

•Pump Schedule•Reservoir Design•Electricity Consumption

•Urban water consumption time series has obvious fractal characteristics (J.Q. Liu 2004).

Methodology

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Study area Details

Source of Water

Kanhan and Pench River

Supply Mode Intermittent (Gravity Fed)

Supply Hr 6:00 to 7:30AM

Length of Transmission

Main (700mm)6.4 km

Length of pipes in Distribution

Network11.4425 km

Length of Service Pipes 5 m

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Figure No.

Study areaDescription

1 Pilot Study area

2 IKONAS Image

3 Pipe and Nodes

4 Thiessen Polygon

5 Houses

1 3

4 59

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Pipe Type

Year of Installation

Roughness Before Calibration

Roughness After Calibration

CI 1980 75 122

CI 2003 to 2011 130 141

DI 2003 to 2011 140 140

GI 2003 120 120

MS 1980 90 122

Calibration and ValidationLocation ID Latitude Longitude Mean pressure

(Meter)Mean Flow Rate (lps)

34 21°08`09.0`` N 79°05`47.6`` E 1 0.15

104 21°08`02.7`` N 79°05`54.0`` E 1 0.16

100 21°08`03.8`` N 79°05`55.8`` E 0 .35

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Location ID

Observed Mean pressure (Meter)

Computed Mean pressure (Meter)

Observed Mean Demand (lps)

Computed Mean Demand (lps)

34 1 1.11 7.50 7.50

104 1 1.05 4.80 4.80

100 0 0.01 8.75 6

Location ID

Mean Error of pressure

Mean Error of Demand

34 0.110 0

104 0.046 0

100 0.006 2.75

Correlation Between Means of Pressure: 0.945

Result And Discussion

Pressure condition for Intermittent Water Supply Continuous Water Supply

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Affected population number is 4065

Transmission Main (700mm)

Parameter Before Calibration After Calibration

Velocity (m/sec) 1.15 1.57

Unit Head loss (m/km) 3.24 3.25

Distribution main (400mm)

Velocity (m/sec) 2.31 3.61

Unit Head loss (m/km) >5 >5

•From this table it is clear that the diameter of the Distribution main is insufficient.

•Total 34 nodes are under pressure of 1 meter, where as minimum recommended pressure is 7meter (CPHEEO, 1999).

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Results after Validation

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Conclusion

• Both intermittent and continuous water supply modes were simulated successfully using

EPANET.

• The pilot area is under very low pressure.

• The continuous supply simulation results relatively higher pressure value, less than 12

meter.

• It is recommended to avoid the direct tapping of water from the transmission main, rather

it is advised to build an elevated service reservoir (ESR) for the pilot study area to maintain

the hydraulic integrity.

• The identified leakage points need to be repaired.

• This particular information is very essential for Nagpur Municipal Corporation to improve

the existing system for effective pressure and flow management

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ReferenceBhave, P. R., (1988): Calibrating water distribution network models. Journal of Environmental Engineering, 114:1, pp.120–136.

Feder, J., (1988): Fractals. New York: Plenum Press.

HydroGen (Hydraulic Model Generator) Version 2.2. (n.d.). ArcScripts Home - ESRI Support. Retrieved September 1, 2012 Archive, On line at: http://arcscripts.esri.com/details.asp?dbid=10117

Jethoo, A. S., & Poonia, M. P., (2011): Water Consumption Pattern of Jaipur City (India), International Journal of Enviromental Science and Development, 2:2, pp. 152-155.

JNNURM. (n.d.). JNNURM. Retrieved September 10, 2013 Archive, On line at: http://jnnurm.nic.in/

Manual on water supply and treatment (3rd ed.) (1999): New Delhi: Central Public Health and Environmental Engineering Organisation, Ministry of Urban Development.

Ministry of Urban Development. (n.d.). Ministry of Urban Development. Retrieved September 5, 2012 Archive, On line at: http://urbanindia.nic.in/

Peter, I., Zdenek, S., Pradhan A. and Tarai A., (2006): Modeling Intermittent Water Supply Systems with EPANET, 8th Annual WD Symposium, EPA Cincinati, August 27-30.

Qian, B. R., (2004): Hurst exponent and financial market predictability. IASTED conference on Financial Engineering and Applications (FEA 2004). pp. 203-209.

Rossman, L. A. (2000): EPANET users manual. Cincinnati, OH: United States Environmental Protection Agency, Risk Reduction Engineering Laboratory.

Vairavamoorthy, K., Gorantiwar, S.D. And Pathirana A (2008)., Managing urban water supplies in developing countries-Climate change and water scarsity scenarios, Physics nad Chemistry of earth, 33, pp. 330-339.

Walski, T. M. (2003): Advanced water distribution modeling and management, Haestead Press.

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