• National Water Supply and Drainage Board

    Greater Kurunegala Water Supply and Sewerage Project

    Kurunegala, North Western Province, Sri Lanka

Project Summary


The National Water Supply and Drainage Board (NWSDB) undertook this LDR 5.9 billion project to improve the living conditions for people in and around the city of Kurunegala, North Western Province, Sri Lanka, by providing safe drinking water and adequate sanitary facilities. Providing proper sewerage facilities for Kurunegala Teaching Hospital was a priority. Measures were also taken to prevent pollution of Kurunegala Lake and the surrounding groundwater system.


NWSDB created hydraulic models of the water and sewer networks using WaterCAD and SewerGEMS, respectively. The software enabled the project team to explore multiple options and scenarios for a network serving the municipal council area and part of the adjacent Theliyagonna area. The solution for improved sanitation included construction of a 4,500-cubic-meter-per-day sewerage treatment plant, 138 kilometers of gravity sewers, six pump stations, 3,500 house connections, and improvements to the hospital network.


The project improved access to safe drinking water with an expanded water supply system that included a 100-meter weir across the Deduru Oya river, a 90,000-cubic-meter storage tank, a new intake structure and 8.5 kilometer raw-water transmission main, expansion of the water treatment plant from 9,000 to 14,000 cubic meters per day, rehabilitation of the 110-kilometer water distribution network, 6,500 new service connections, and a continuous water supply for the hospital.


Using WaterCAD to design the water supply network allowed NWSDB to run multiple scenarios to optioneer the best outcome. The scenario management tool shortened the time it would have taken to consider various design options, and allowed more scenarios to be considered. WaterCAD and SewerGEMS also interoperated with ArcGIS for the data mapping. Data from field surveys was analyzed and entered into the GIS, providing informed hydrological modeling and analysis throughout the project lifecycle.

  • The new sewerage system protected the Kurunegala Tank, which had been exposed to pollution due to wastewater discharge from surrounding dwellings.
  • The water supply network provided Kurunegala Teaching Hospital with a 24/7 water supply for the first time.