Uncoordinated Management of Karnafuli River Basin 5 World

Uncoordinated Management of Karnafuli River Basin 5 World water Forum Session 6. 2. 3 Emaduddin AHMAD, PEng. Executive Director, Institute of Water Modelling 21 March, 2009 1

Management of Karnafuli River Basin Total basin area: 12, 500 sq. km. (approx. ) INDIA Creation of two lakes after 1962 Lake area: 780 sq. km. Kaptai Hydro Power Plant 3500 cumec 2

Chittagong 3

Hydropower Flood alleviation 80% inflow in monsoon 66% release in monsoon Flow augmentation Salinity control WTP Power. Plant City Port F. Factory 4 Power. Plant Paper & Rayon mill Navigation Kaptai dam

Current practice and issues in Karnafuli Basin management After 46 years of operation Upstream issues Baghaichari Rule curve for reservoir operation Downstream issues Nannerchar Langadu Flood-free environment and Water quality adequate irrigation water Drainage potential City Port Siltation F. Factory 5 WTP Power. Plant Salinity control Cooling Rangamati water depth Paper & Kaptai dam Rayon mill Water flow for effluent discharge and navigation Fringe area inundation / drying Barkal Water availability Additional Power generation Optimum dam release and sustainable river flow can resolve many of these issues. Mathematical models provide required analytical basis in an integrated way to make appropriate decisions.

Salinity level at the Mohra Water Treatment Plant January-March, 2007 Allowable limit: 600 mg/l Causes of Salinity Build-up at Halda outfall (Mohara) Decrease in freshwater flow from upstream High tide level 6

a Mohra Water Treatment Plant experienced highest level of salinity (up to 11500 mg/l in place of the general range of <600 mg/l) in 2007, spawning is lost for a very special type of carp 7

Adverse effect of uncoordinated dam release • Salinity at Mohora Treatment Plant rose to 12000 ppm resulting closure of treatment plant causing enormous suffering to people of port city • The rare species of carp at Halda (requiring specific level of salinity) has been disappearing since last few years All these require an ensured supply of fresh water from reservoir during January to April (even by resheduling the power generation – but it did not happen) Similar event occurred this year due to release of flow in earlier months with no regards for urban water supply. An institution to negotiate with appropriate tool is absent. 8

Reservoir Operation Model A Decision Support System (DSS) for Optimum Reservoir Operation Main Interface of ROM Databas e Inflow prediction Simulatio n Result presentation 9

Reservoir Operation Model Result presentation module 1 10 2

Reservoir Operation Model Inundation mapping module Operation dependent land availability Helped to build confidence in ethnic groups 11

Conclusion Salinity rise at Mohra or irrigation water shortage at halda/Ichamoti is only due to absence of basin level planning and operation. A River Basin Organisation (RBO) can be a suitable platform to implement IWRM. How to work with agencies having diversified ineterst and chain of command 12

Institutional Need Institution required for • Equitable participation of stakeholders • Output dissemination • Participatory planning • Sharing knowledge/constrain Tour operator Flood map Fisheries and navigation Water level and Extent Upstream farmers Flood map IWM Feedback & update Public representatives/ NGO/Local administration Industries Tail water level BWDB Reservoir release Tail water level 13 BPDB Inflow forecast, Spillway release, Flood map Tail water level Flood map

Institutional Framework Water Resource Planning Organization River Basin Unit Downstream stakeholder committee DSS housed at PDB, Kaptai Upstream stakeholder committee Initial setup of RBO under WARPO with DSS is being worked out 14

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