1 Uncoordinated Management of Karnafuli River Basin Emaduddin AHMAD, PEng. Executive Director, Institute of Water Modelling 21 March, World water Forum Session 6.2.3

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

3 Chittagong

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

5 Paper & Rayon mill Port City F. Factory WTP Kaptai dam PowerPlant Rangamati Nannerchar Langadu Barkal Baghaichari Current practice and issues in Karnafuli Basin management Fringe area inundation / drying Water flow for effluent discharge and navigation Water availability Additional Power generation Cooling water depth Salinity control Water quality Flood-free environment and adequate irrigation water Siltation Drainage potential 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. Rule curve for reservoir operation Upstream issuesDownstream issues After 46 years of operation

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

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

8 Adverse effect of uncoordinated dam release Salinity at Mohora Treatment Plant rose to ppm resulting closure of treatment plant causing enormous suffering to people of port city Salinity at Mohora Treatment Plant rose to 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 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.

9 Reservoir Operation Model A Decision Support System (DSS) for Optimum Reservoir Operation Database Inflow prediction Simulation Result presentation Main Interface of ROM

Reservoir Operation Model Result presentation module

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

12 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

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

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

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