JICA conducts seminar on PC Tank Construction for NWSDB Staff

Embassy of Japan in Sri Lanka Minister Toshihiro Kitamura 

delivering the key note speech at the seminar

Extending further support to improve the reliability of the nation’s water supply system, the Japan International Cooperation Agency (JICA) organised a seminar recently with the National Water Supply and Drainage Board (NWSDB), to disseminate knowledge on designing and constructing of Pre-Stressed Concrete Tanks (PC Tank) in Sri Lanka.

The seminar was held on 14 March with Embassy of Japan in Sri Lanka Minister Toshihiro Kitamura as the Guest of Honour. JICA Chief Representative Fusato Tanaka and NWSDB General Manager Deepthi Sumanasekara also graced the occasion, together with the other officials of JICA and NWSDB.

Previously, JICA had extended assistance for the construction of a PC tank at Beruwala. This tank was ceremonially opened on 26 July 2018 by City Planning and Water Supply Minister Rauff Hakeem, and the then Ambassador of Japan in Sri Lanka Kenichi Suganuma.

Built though Japanese private company, Abe Nikko Kogyo Co. Ltd., the PC Tank has a structure that introduces pre-stress by steel in its wall, which makes the tank durable against cracks and leakages caused by the water pressure from the inside of tank. 

Another advantage of the PC Tank is less cost, as it requires less concrete and minimum rebar due to its pre-stressed structure compared to Reinforced Concrete tank, which is commonly used in Sri Lanka. 

It can also be constructed in a small land plot, as the height of the tank is not a limiting factor because of its durability. Abe Nikko Kogyo Co. Ltd had developed technology of PC tanks in 1957 and is a pioneer of PC tanks, currently having 60% of PC tanks constructed in Japan. 

The company constructed the PC Tank in Beruwala with construction technology called “Air-Dome Technology” which uses air domes instead of scaffolding. It realises safe and speedy construction. 

Collaborating on the project, the NWSDB had also implemented the project component of upgrading the transmission mains from Kethhena Water Treatment Plant and upgrading of the pump houses in Beruwala and Darga Town in parallel with the PC tank construction. 

These interventions improved the service level of 40,000 existing water supply connections by ensuring 24-hour supply.  They also helped the creation of another 20,000 new water supply connections in both Beruwala and Darga town.  

Commenting on the seminar, Fusato Tanaka stated, “The PC tank could be a feasible solution for water supply projects in Sri Lanka, especially in rapidly developing areas such as Colombo where finding big lands for water tanks is difficult while the need to supply water is increasing.”

He further stated that JICA also supports providing safe water and improving the efficiency in water supply in Colombo and Kalutara Districts through the Kalu Ganga Water Supply Expansion Project.