Treasury Granted Projects under Special Projects
DRAINAGE STUDY FOR MADIWELA SOUTH DIVERSION SCHEME
Funding Agency : Government Treasury
Proposed Madiwela South Diversion is diverting the storm water from an area of approximately 14 km2 of the upper catchment of parliament Lake into the Weras Ganga basin. This area presently drains in to the Greater Colombo basin and this diversion will reduce the water levels in Parliament Lake and Colombo canals by a considerable amount.
Madiwela South Diversion contributes to 50% of the total water level reduction in Parliament Lake and therefore it is of major importance for reducing floods in Colombo.
The feasibility study for this diversion has already been done in a study carried out under Japan International Cooperation Agency (JICA funds) in 2003.
Since this is a trans-basin diversion, a detailed hydrological study has to be done on this and measures are to be proposed in order to mitigate the adverse impacts to the Weras Ganga basin. A time duration and a cost estimate for the project can only be finalized once the conceptual designs are finalized after the hydrological study.
Approximate cost estimate for this project is Rs. 5000 Mn.