JICA gives Lanka Rs. 108 m grant to construct concrete tank in Beruwala

The agreement between Abe Nikko Kogyo Co. Ltd. of Japan and KDA Weerasinge & Co. Ltd. of Sri Lanka being signed

Text and pix by Ashraff 

A. Samad

Abe Nikko Kogyo Co. Ltd. of Japan and KDA Weerasinge & Co Ltd. of Sri Lanka signed an agreement for the construction of a 2000Cum capacity prestressed concrete ground reservoir in Beruwala as a pilot demonstration project for the National Water Supply & Drainage Board. 

Japan International Cooperation Agency (JICA) Sri Lanka office representative Yusuke Shinozaki, National Water Supply and Drainage Board (NWSDB) senior managers Eng. D.U. Sumanasekara, Additional General Manager (Water Supply Projects), Eng. T.W.S. Perera, 

Deputy General Manager (RSC - Western South) and Eng. M.M. Umar Lebbe, Assistant General Manager (Japanese Project Unit) were present for the contract signing ceremony.

The towns of Beruwala, Aluthgama and Bentota are situated along the coastal line in the Kalutara District of the Western Province. A potable pipe water supply for these towns is supplied by the Kethhena Water Treatment Plant located in Kalutara. Beruwala is located 21 km from the Kethhena Water Treatment Plant. The existing Beruwala ground reservoir distributes water to Beruwala, Aluthgama and Bentota.

There are 17,000 water connections available in these towns while there are 2,000 applicants on a waiting list to get new connections. Currently, applications for new connections from these towns have been temporarily closed due to the inadequate storage of water in Beruwala. 

Furthermore, there is demand for about 15,000 new connections in Beruwala, Aluthgama and Bentota. Currently water is supplied only for 12 hours a day to Beruwala, four hours a day to Aluthgama and a few hours on alternate days to Bentota.

As these towns are located close to the sea, the quality of well water is questionable. These towns are also very heavily populated and there is no sewerage system except in parts of Bentota. Septic tanks are also located close to existing wells. Therefore, there is high demand for a potable pipe water supply. 

NWSDB is unable to meet the demand of these people due to the inadequate capacity of the storage tank at Beruwala. Furthermore, Bentota is a tourist hub with a high demand for water.

Currently, the capacity of the storage tank available in Beruwala is only 1350m3. The existing transmission line from Kethhena to Beruwala reservoir consists of two sections - a 600 mm diameter DI line from Kethhena to Maggona and a 350 mm diameter AC line from Maggona to Beruwala. 

NWSDB has already replaced the 350 mm diameter AC section with a 600 mm DI pipe. The size increment of the above transmission line has reduced the pump head requirement at Kethhena by 17 m. This head reduction will make it possible to pump an additional quantity of 10,600 m3/day of water from Kethhenato to the Beruwala ground reservoir. 

It is urgently required to increase the water storage capacity at Beruwala by an additional 2000 m3. NWSDB could not find funds to construct this water storage tank. NWSDB has already taken action to replace the existing high level pumps at Beruwala in order to distribute the increased quantity of water. The land required for the construction of this reservoir has already been purchased at a cost of Rs. 6.9 million, utilising Government funds. 

The provision of additional water storage capacity in Beruwala will provide immediate benefit to the existing 17,000 consumers, who will get an improved water supply for 24 hours, it will be possible to provide 15,000 new connections and the total population of about 192,000 living in Beruwala, Aluthgama and Bentota can enjoy the benefit of this JICA grant provided to the Sri Lanka Government. It has been proposed to complete the construction of this tank within a six-month period. 

The construction of a pre-stressed tank with the air dome construction is common in Japan but it is first time it is being used in Sri Lanka. JICA wished to introduce this technology in Sri Lanka due to speedy construction, minimum land use and the high durability of the tank while the cost is less for larger capacity tanks compared with conventional water storage tanks. 

Furthermore, JICA has also made arrangements for the technology transfer of air dome prestress concrete tank construction and designing to Water Board engineers by sending them to Japan. It will help the Water Board engineers design and construct PC tanks with air dome technology in the future.