III.           OUT LINE OF THE MASTER PLAN

 

3.1       The approach

      The general problems of approach in the Master plan are as are as follows:

     

(a)        Having first met the irrigation requirements of the lands in the Mahaweli Ganga and Maduru Oya basing the remaining water may be diverted for irrigation in the north central province.

 

(b)               The expansion of irrigation to new areas will be considered only after an adequate water supply assured for the existing irrigation schemes within the boundaries of the irrigation systems.

 

(c)        New  Irrigated  lands  should be located within command of the newly  designed  tanks  which  cater for  the  existing  irrigation schemes.

 

(d)               Water supply for irrigation should be provided in the adequate quantities all through the year and in not less than 85 present of year.

 

(e)                Water supply for hydro-electric stations at designed rates to generate firm power should be available in not less than 90 present of year.

 

3.2              Main Features of the Master Plan

 

             The survey of the water resources of the Mahaweli Ganga an its  tributaries showed that after providing for irrigation of all available land in the Mahaweli basin itself, roughly 40 percent of the regulated water would remain, which could be diverted to the north-central part of the island.  Of the total 900,000 acres which could be supplied with water for irrigation a little more than half lie in the Mahaweli and Maduru Oya valleys and the remainder in the north-central part of the island, as already mentioned. 246,000 acres are presently cultivated and 654,000 acres are mostly uncultivated.  As the uncultivated acres are State –owned it is anticipated that problems of resettlement and land purchase will not be overwhelming'

 

            The Master plan envisages storing some six million acre feet of water in 15 reservoirs located on the Mahaweli Ganga rive, its tributaries and the Maduru Oya. Eleven of these reservoirs include power station near the dams. And another power station is located on a trans-basin canal. The installed capacity of these stations would be 508 megawatts. The total output of firm power would be 2,037 million k W h. per year and this corresponds to about half of what is required by Ceylon

1990.

 

            The main reservoirs are Randenigala and Victoria for the irrigation supply of the Mahaweli

Basin

and Moragahakanda, Polgolla and Kotmale for the north central part. The regulation of river flows with the help of these reservoir would result in and additional benefit of flood control over 200 squire miles of the lower flood plan and delta would be reclaimed, and the agricultural area; around two northern townships would be protected from the periodic inundation from which they presently suffer.

 

            The irrigation areas included in the Master Plan are group into 14 irrigation systems. Eight of these (A, B, C, D-1, D-2, E, F, G) with a total irrigated area of 470,000 acres are located in the Basin of the Mahaweli Ganga and Maduru Oya. The remaining six systems (H, I, M, K, J) are in the north-Central part.

           

The cost of the centre project, which provides for irrigation, irrigation, drainage, flood protection, Land development and settlement, and power production, is estimate at Rs. 5,583 million¹, including the cost of land clearance and the irrigation work required for the delivery of water to the fields.

 

1          Unless otherwise noted, all currency figures are based on the post devaluation rate of Rs. 5.95 US $ 1.00.