P-SC-EA0-004

Project Details
ID: P-SC-EA0-004 Name: MAHE SUSTAINABLE WATER AUGMENTATION PROJECT Status: Ongoing Country: Seychelles
Sector: Water Sup/Sanit Approval date: 01-Apr-2015 Task Manager: MUTASA Christopher, RDGE2
Total cost: 17789327.75
Currency: UAC
Source(s) of financing
AfDB: 13894697.08
Government: 2694626.93
MICF: 1200000
Implementing Agency: WATER AUTHORITY PUBLIC UTILITIES CORPORATION Location: Mahe Island, Victoria

Benefits

The WDP specifically recommends the immediate raising of the height of La Gogue Dam on a priority basis to increase the water storage capacity.According to previous studies and WDP, raising of the height of La Gogue dam by about 5m would alone increase the reliable yield by an average of 3,900m3/day. This additional resource is equivalent to about 50 days of water for the Islands representing 14% of water currently produced. The other alternative considered for storing water was the building of a new dam on the Grand Anse River. However this alternative was dropped due to the environmental concerns and engineering complexities. The raising of the La Gogue dam was therefore deemed the most attractive option due to the amount of fresh water storage to be achieved and the potential for transfer of water from adjacent surplus catchment. The raising of La Gogue dam is therefore a strategic water security enhancement scheme for Seychelles and there is need to further investigate this option to confirm the feasibility of the scheme. The development of this scheme, if feasible, will further provide the possibility to improve the La Gogue distribution zone with the construction of La Gogue water supply treatment plant (gravity fed system) resulting in net cost saving over longer period from the present energy intensive distribution system in La Gogue area, thereby contributing to the mitigation of climate change. This region is considered to have intermittent supply due to problem of low pressure and long distances from the existing treatment plants at Hermitage and Le Niol. There are 12 pumping stations within this area with high energy costs. In order to reduce these constraints, a new system is proposed, namely the construction of a new treatment works at La Gogue providing supply directly to this distribution zone.