Integrated Urban Water Resources Management in Sri Lanka Background, Issues and Training Needs

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1 Integrated Urban Water Resources Management in Sri Lanka Background, Issues and Training Needs N.T.S. WIJESEKERA Department of Civil Engineering University of Moratuwa, Moratuwa, Sri Lanka

2 SRI LANKA The Democratic Socialist Republic of Sri Lanka An Island in the Indian Ocean surrounded by tropical beaches Latitude 5'55" - 9'51" & Longitude 79'42" - 81'52". Total land area is 65,610 sq. km Length-445 km Breadth- 225 km 870 sq km of inland water (1.3% of total)

3 Population of Sri Lanka is about 20 million Density is highest in the southwest : Colombo 74% of the population are concentrated in the southwest 21.5% Live in Designated Urban Areas The net population growth is about 1.2%.

4 In Colombo and Suburbs Impervious Area is varying around 25 40% in residential areas In commercial area this is approximately 95%

5 Major Urban Centers Colombo Kandy Galle

6 Jaffna Other Urban Centers Anuradhapura Trincomalee Negombo Kurunegala Matara

7 Jaffna Close to Water Bodies Anuradhapura Trincomalee Lake Ocean Negombo Colombo Kurunegala Kandy Matara Galle River Delta, Habour, Low Lying, Land Filling, Water Intakes, Drainage

8 75% Urban and 14% Rural are served with Pipe Borne Water Demand for safe water increases by 8-10% each year Most urban water supply schemes do not have the capability for 24 hr service

9 The Water Supply Sector Expenditure 50% 40% 30% 20% 10% 0% Getting Reduced

10 Water Sector Issues in the Urban Areas of Sri Lanka Urban Water Supply and Sanitation Urban Area Flooding Quality of Water Bodies

11 Urban Water Supply Sources: Mostly,- Surface Water Several, - Groundwater Colombo Surface water from Kelani and Kalu Rivers Kandy Mahaweli River Galle Gin River Water is pumped from Rivers to storage reservoirs and replenished Water availability is the availability of river flow: In the Dry Season Salt water intrusion: (Elevation increase of Kelani and Gin Barrages) Storage Reservoirs have limited Capacity and no expansions have been done in the recent past

12 Demand for Domestic and Industrial Uses are calculated based on Daily Demand and the availability of sufficient storage until replenished Mid Night Noon 6 PM Groundwater is pumped from deep aquifers. Wells are designed accordingly but the monitoring of the aquifer status other than the quality of water is not done during extraction (in any of the schemes)

13 Urban Water Supply Training Needs: Hydrological Assessment of the Source Watersheds and Data Collection Needs Source Area Engineering and Management Basin Planning with adequate inputs from other sectors to identify the availability for expansions System study techniques to identify alternative solutions (to incorporate supplementary storage to overcome dry season problems etc) Groundwater Aquifer Modelling and Data Collection needs Groundwater enrichment developments and infrastructure

14 Water Demand for Pipe Borne water Pipe borne water at doorstep is available to only 29% of the population NWSDB has done several studies in specific areas and identified that the unaccounted for water is approximately 40-45% It is introducing demand management techniques. In some areas introducing GIS based models along with metering to identify loss zones for remedying Identified that rainwater harvesting should be promoted No studies are done to determine the actual demand rates or to identify the optimum allocations for system designs

15 Training Needs: Demand assessment techniques Incorporation of land occupancy variations/spatial variations for the pipe network modeling to arrive at better estimates Spatial Database or GIS based design techniques for the establishment of such units to carryout proper assessments in a changing environment Assessment of System Losses through measurements and modelling with sensitivity analysis to embark on better water management

16 Urban Area Flooding Houses of mostly low income under water Roads become impassable Disrupts economic activities Causes traffic congestions Accidents, Vehicle Maintenance Pedestrians in a great difficulty Splashes from passing by vehicles, Water Pools to walk in Water logging and poor drainage deteriorate road surface - huge repair costs Mosquito Breeding, overflow of septic tanks, dirty drainages causes health hazards

17 Being in the wet zone of Sri Lanka Most Urban Centers are experiencing rain almost throughout the year, this is a bigger concern than the water supply. (Urban Status-Flooding and Drainage intolerable) Being an island, in Sri Lanka, urban storm water management is vital because most of our urban centres are either located in a river valley, in or close proximity to an estuary, or by the side of a lake. The identified causes for urban flooding - indiscriminate filling of lowlands, Alteration of Drainage Paths, increase of impervious areas, and inadequate drainage designs, and lack of adequate legislation and commitment

18 In Colombo the water and marshy wetlands had been nearly 52% but presently the water bodies and remaining marshes occupy only approximately 5% of the land area.

19 Water Bodies Marsh Commercial, Residential Sanity, Vacant, Utilities

20 Modification of the drainage system and Encroachments

21 The Hydrological assessments are done with models which have not been verified or having less than minimum verifications There are no gauging stations with reliable stage discharge curves Except on a project wise, short term basis the RF is not gauged at a spatial resolution satisfactory for urban hydrological models Legislation covers only large scale developments: cumulative effects are ignored. Flood Detention and Retention concepts are still with the engineers awaiting acceptance of the politicians

22 Training Needs: Urban Hydrology and Drainage issues in low lying and downstream controlled situations Floodplain Management-Flood Retention and Detention concepts, Design of infiltration facilities etc. Methods for Public awareness increase and public corporation achievement Development of Spatially distributed models using GIS to identify impacts of filling and encroachments Network Designs-Establish proper stations RF & SF gauging Compute and Identify Appropriate Design Storms

23 Quality of Water Bodies

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25 Locations of Continuous Monitoring of Water Quality & Levels 1 NORTH LOCK OUTLET TO KELANI HIGHLY POLLUTED CANALS 2 3 Kittampahuw a Ela 4 5 Se a Water sampling point

26 Training Needs: Water Quality modelling in GIS and identification of Dilution factors Lowflow periods, consequences with floods Community Awareness of Waste and Wastewater Disposal Effects of Disposal on Hydrology and water quality Ecological Modelling to Identify alternatives solutions to improve already polluted water bodies Design and maintenance of wetlands for water quality improvement and flood detention and retention Eco Tourism and river environment improvement concepts Benefits for low income groups and avenues for income generation

27 Governance Issue The Urban Development Authority under the Ministry of Urban Public Utilities is vested with the task of integrated planning and implementation of economic, social and physical development of urban development areas in the country, which are specific areas declared by the Ministry UDA is vested with very strong powers

28 Governance Issue Water Supply NWSDB is responsible for 95% of the Supply Two Ministries + Two Authorities + Two Boards and one Department, are involved in the Urban Water Supply and Sanitation services interrelation between them is complex The NWSDB has identified funding problems and therefore promotes private sector investments

29 It has already been identified to establish an industry specific water regulator To ensure better water quality, it has been identified to promote a industry citing policy in relation to water intakes There isn t a clear cut policy on water sharing between different competing agencies

30 Governance Issue Storm Water and Drainage SLLRDC Sri Lanka land reclamation and development corporation is the main agency. UDA and the Agrarian Services corporation also play major roles CEA the regulating authority ID Flood forecasting and fighting

31 Local Authorities such as Municipal councils, provincial councils, Urban Councils are also responsible for the land use and storm water management

32 Issues and constraints Unclear responsibilities among state agencies for Storm water drainage works. (Different agencies have different areas of jurisdiction which are unclear) Lack of an authorised landuse plan for urban centers case by case gives rise to malpractices

33 Malfunction of the Regulation system for low land development -No comprehensive statute for land use regulation -No proper evaluation system for land filling proposals -No guidelines backed by studies to identify detention needs

34 Training Needs Institutional needs and policy framework for good governance Public and State corporation for sustainable environmental planning and management of storm water infrastructure Methods of identifying scientific studies to support policy formulation

35 Conclusions For Sri Lanka it is important that the water supply, storm water management and water quality training is strengthened to ensure a sustainable urban environment. The urban hydrology along with analysis techniques through available models should be taught incorporating the aspect of both spatial and temporal variability

36 The training would have to incorporate a component on group work case studies for practicing water professionals to identify appropriate solutions. The training should attempt to incorporate the techniques of working with the public not only at the implementation of solutions but also for data collection, selection of decision making criteria and making guidelines

37 Training could include short term training (seminar type) on new methods, Techniques, Technology awareness (senior, middle, technical) Training could have short term, hands on training for middle and technical personnel Collaborative (industry experience) postgraduate degree programs with state and other funding assistance (for the young and the enthusiastic) have to be the foundation

38 The End Thank you