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Asia Geospatial Forum, Hanoi 18 September 2012 Vikram Singh, Delhi Jal Board, India Kapil Chaudhery, Spatial Decisions, India Kazufumi Momose, Tokyo Engineering Consultants, Japan. Master Plan for Delhi Water Supply Responding to Rapid Urban Infrastructure Growth Using GIS. Overview.
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Asia Geospatial Forum, Hanoi 18 September 2012 Vikram Singh, Delhi Jal Board, India Kapil Chaudhery, Spatial Decisions, India Kazufumi Momose, Tokyo Engineering Consultants, Japan Master Plan for Delhi Water SupplyResponding to Rapid Urban Infrastructure Growth Using GIS
Overview • Water supply systems are typically developed incrementally over the decades and combine assets that have been integrated into the overall system at different points in time, in response to changing demand and urban growth patterns. • The rapidly growing city of New Delhi covers an area of almost 1600 sq.km, with a distribution network of over 10,000 km of pipeline, with a current population of approximately 16 million and a projected service population of 23 million people projected for the year 2021.
Cont. … • The challenges of a developing a water supply master plan for such a large area and high population load: • spread across 22 management zones, a logistical challenge • compounded by the fact that city government administrative zones are different from water supply zones • That administrative decisions impact population density and land use, which has a direct impact on the water supply system planning • That these changes continue to pose a logistical challenge in developing a comprehensive master plan while responding to short term and localized problems
Role of GIS • GIS provides the seamless base and interface upon which to establish immediate short term actions yet link them with long term master plan activities • At a master plan development level, GIS facilitates: • Evaluation of multiple scenarios of water supply load estimation based on the land use and urban governance. • Examines options in the face of limited fresh water availability • Evaluates impact of policy decisions like 24x7 water supply • Helps optimize a supply and distribution network based on current available assets, their operative condition, and anticipate new assets required of appropriate design at optimal locations
The GIS Environment • Delhi Jal Board has a dedicated GIS/ Mapping centre • The entire database is maintained on a dedicated server using ArcGIS from ESRI as the GIS engine and Oracle as the relational database • This establishes a foundation for geospatial information management on its entire water collection, treatment, and supply systems • Recent QuickBird and CartoSAT imagery serve to establish a more updated geo-referenced base upon which to position the asset inventory • WaterGEMS was introduced into the basic GIS infrastructure to support the hydraulic modeling and system design for the master plan
Developing the Master Plan: Baseline • The water supply master plan starts with the following known information: • Land Use and Development Master Plan 2021 from the City Urban Development Department • Information on existing network and capacities available in the DJB GIS Center • Established government policies on water supply standards and norms • Fresh water availability scenarios indicate limited capacities
Developing the Master Plan: Challenges • The peculiar challenges of this master plan development are: • The network mappings needs to be verified and updated. About 10,000 km of network spread over 1,600 sq.km! • An urban development master plan for the year 2012 is the foundation but is at variance from ground reality of land use activities • There is a massive, yet undocumented, unverifiable amount of leakage of treated water in the supply network • And this does not cover the non-revenue water, i.e. water that is supplied but for which revenue is not collected • Variability in supply results in some people being flooded with water and some getting no water
Objectives of Master Plan • The objectives of the Water Master Plan is clear; to prepare well in advance optimal water supply facilities to meet water demand. The target year is set as year 2021 same as the target year of the Master Plan Delhi 2021 (MPD2021). Its objectives are specifically identified and agreed with DJB as shown in below table.
Converting Land Use into Water Demand • The urban development plan provides for designated land use types • The urban planning development norms provide indicative values of water supply demand by land use activity • Any changes in land use will impact water demand by geography
The Water Demand by Land Use • Using the land use plans for each administrative zones, the water demand is established by its geospatial distribution
Fresh Water Availability • With the limited availability, Delhi is staring at a serious resource constraint • To meet this, we will have to turn towards resource conservation and waste water recycling.
Analyzing the Water Supply System using GIS • From a master plan modeling perspective, we critically require information on the network: • Transmission mains • Secondary Mains • Distribution Lines • And linked to the network we need information on the supply capacity of the treatment plants and the under ground reservoirs (UGRs) which serve as localized distribution requirements • A critical step then becomes to assess the existing UGR distribution and their capacity
Using GIS to Develop the Water Supply Master plan • Water Gems used for modeling. • Water Gems and Arc GIS Used for Pipeline Network Modeling. • After modeling Proposals can be made • Replacement • Repair • More Demand Area • Efficient Network Data. • Capacity and Serving capacity of an UGR. • Pipe line Network Monitoring. • Timely Updating. • Development of GIS Data • Management of Assets. • Pipe Line Network. • Transmission mains • Distribution Lines. • Valves, Booster Pumps • Tube Wels • UGR’s • WTP’s • Management of Attribute Data and timely updating the data is a biggest challenge.
Development of Network Data The GIS system is capable of displaying any water supply facilities on the map. The entire network along with the condition assessment data based on extensive field work is archived into the GIS database Its locational accuracy and its corrected attribute data are critical data for the modeling and system planning process.
Distribution System Length of existing distribution pipelines is approximately 7,000 km spreading across 22 water supply zones in Delhi. Layout of Existing Distribution Pipeline
GIS-based Network model from UGR to DMA’s Allocation with DMAs in Non-revenue Water Study, and with Control Valves Flow meters and Pressure Meters in SCADA Study
Attribute data management and updation Pipe Line Attributes Pipe Line Distribution Network Pipe Lines
Optimizing UGR zones using GIS • DJB currently operates with 125 UGR command zones. • Each UGR is examined to assess • Capacity-Demand mis-match • Availability of space to enhance UGR if necessary • Reduction in service area of existing UGRs and adding new UGRs • This iterative process requires an optimization at a sub-city supply-watershed level, based on existing and planned enhancements to treatment capacities • Added complexity is the hydraulic variability across the city terrain and the need to optimize location of treatment facilities and pumping stations to achieve this
District Metered Areas (DMAs) • 1,011 District Metered Area (DMAs) across the city need to be optimized, using GIS
Using GIS for Optimization Analysis • Working interactively between the GIS database and the thought process of water supply engineers, fits the GIS-enabled tool, WaterGEMS from Bentley. • This product, albeit expensive, with the appropriate training, provides us with the capacity to interactively analyze and plan the entire city level system, although in reality addressing it in smaller subsets.
Use of Water GEMS for Modeling Network modeling Modeling results
Arc GIS and Water-GEMS Integration Arc GIS Queries Arc GIS Data Water Gems Tables Water Gems Scenarios
Case Study of UGR Command Area PlanningD-09 JAL VIHAR Study-3:MP/FS Sonia Vihar WTP Jal Vihar
Existing Condition Study-3:MP/FS The existing situation at Jal Vihar
Hydraulic Analysis-Result of Existing Condition Study-3:MP/FS • Hydraulic Analysis of the existing condition • Negative pressures can be clearly seen • Pump Specifications • Capacity - 59 MGD • Head - 43 Meters • Distribution Mains Length – 21.03 Kms
Planning of DMA Study-3:MP/FS • The UGR Command zone was further divided into District Metered Areas (DMA’s) • They were assigned Unique ID’s
Planning of Distribution Main Study-3:MP/FS • The distribution mains were planned to reach all the DMA’s • Inlet points to feed the DMA’s were planned • New Mains were proposed • Insufficient Pipes • Pipes not available • To maintain Connectivity
Planning of Distribution Pipe Study-3:MP/FS • The distribution pipes are added to the scenario • Pipes crossing over DMA’s were isolated • DMA were fed through the predefined Inlet Points • New Pipes were planned • Insufficient Pipes • Ensure Connectivity
Hydraulic AnalysisResult of Proposed Condition Study-3:MP/FS • Hydraulic Analysis of the JICA Proposed condition • No Negative pressures can be seen • Pump Specifications • Capacity- 36 MGD • Head- 43 Meters • Distribution Mains Length – 9.5 Kms
Flow Control by SCADA Study-3:MP/FS +31m +24m +32m SCADA is used for water flow monitoring and control. +27m +28m +28m +22m +22m +29m +31m
After Modeling Proposals can be Made • New WTP Command areas • Replacement of Old Pipes • Efficient Network Data • Recent updates can be done using GIS
Conclusion A land use and water demand based approach is applied to prepare a Master Plan for Delhi Water Supply by linking land use and water supply data using ArcGIS and WaterGEMS softwares. The conclusions are: • GIS is becoming the universal backbone in most information systems managing data for water resource and water supply system, the integration and ability to retrieve and (re) use information between GIS and asset management system. • Compared to the traditional population based approach, the land use based approach can more accurately capture trends for future development, which can mitigate uncertainties from different population growth models. • The land use based approach by linking land use patterns with water demand data can provide more accurate projections of demand curves for public water supply as compared to the traditional approach of extrapolating population growth curves multiplied by assumed per capita consumption.
End Notes …….. • This comprehensive, GIS-based water supply master planning process required a significant effort and investment to develop. • To derive continued benefits from this and to support other potential activities for DJB, this system must be maintained and kept updated. • This activity is of fundamental importance, especially as DJB moves towards preparing detailed implementation plans for selected areas within the context of the master plan.