Laboratory Services of National Water Supply and Drainage Board

National Water Supply and Drainage Board Laboratory services are structured as given bellow,

• Central Laboratory Services
• Regional Laboratories
• Plant Laboratories

Each laboratory is under the direction of a Chemist with technical coordination and consultation being provided by an Assistant General Manager (Laboratory Services).

Central Laboratory

Central Laboratory functions as the Center for Water Quality Control. It serves as monitor for the activities of all levels of laboratories.
The Central Laboratory Services implements its sampling and analytical schedule as initiated by the AGM (Laboratory Services). It engages mainly operational monitoring and verification monitoring of water quality, research programs and promotes training. It functions as an active laboratory in water (microbiological, chemical, physical and toxic) wastewater, water treatment chemicals (alum, hydrated lime, bleaching powder, polyaluminium chloride, powder activated carbon & polyacrylamide compounds) heavy metals, volatile organic compounds including pesticides and filter media disciplines. Central laboratory acts in an advisory capacity to process control and serve as the processing center for Analytical data to provide higher management levels in the organization.

Sri Lanka Accreditation Board for Conformity Assessment declares that Central laboratory of National Water Supply & Drainage Board having been found to comply with the accreditation criteria for testing laboratories as described in ISO / IEC 17025 : 2005, has been accredited as a testing laboratory under the field of chemical testing for water treatment chemicals; alum and hydrated lime.

Certificate of accreditation

Metal and Heavy metal analysis 

Atomic Absorption Spectroscopy (AAS)


Atomic absorption spectroscopy (AAS) is a spectroscopic analysis technique that determines the concentration of a particular element in a sample by atomizing the contents of the sample and measuring the absorbance of a wavelength specific to that particular element in the gaseous state.





This is emission mode of spectroscopy and it’s performed to identify and measure a range of chemical elements.






Microbiological Testing

Enumeration of algaes and cyano bacteria are being conducted under this section. In addition to that this is used to observe pathogens and other microbial organisms in wastewater and other water samples in critical situation.


Microbiological Laboratory

Total Coliform Escherichia coli test
Membrane filter method and Colilert method are used to detect and count of Escherichia coli and Coliform bacteria. (SLS 614:2013 / SLS 1461 part 1 section 1 and section 2)


Total Plate Count

Total Plate Count analysis is the calculation of the number of bacterial colonies present in the sample with dilution as needed.

Regional Laboratories

The regional laboratory functions as a field unit with the capability of performing routine microbiological and chemical analyses. The laboratory implements its sampling and analytical schedule initiated by the Regional Chemist. It is responsible for operational monitoring and verification monitoring by engaging with water safety plans to maintain to assure the water quality. An active quality assurance programme is maintained. In addition to that, certain water testing methods have been developed according to the regional water quality issues.

Plant Laboratories

This unit provides the basic data relative to those parameters specified by upper level laboratories. The water treatment plant officers maintain the selected sampling points throughout the system with the coordination of Chemist for the process control of water treatment process. These laboratories are mainly responsible in operational monitoring.


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As an engineering institution handling one of the most important engineering systems of a country, NWSDB has lot of engineering designs and engineering planning works of the water distribution system. The Planning and Designs Section is responsible for handling all the design works and engineering planning of distribution system.


P&D Section operates under the Policy & Planning Divsiion (under the authority of the Addl. GM (P&P)) and headed by a Deputy General Manager (P&D). The division consists of Over 30 specialist engineers specilized in various subject areas in the water and sanitation sectors.

Contact Details:



Key Staff Members:



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Central Workshop is the main workshop to the National Water Supply & Drainage Board and running under Deputy General Manager (Mechanical & Electrical Service). This plays a leading role in the O&M (Operational & Maintenance) Sector, giving assistance to the maintenance of Treatment plants and Drainage Systems.

Sections under Central Workshop
  • Vehicle Section
  • Fabrication Section
  • Pump Section & Machine Section
  • Electrical Section
  • Electronic Section
  • Water Meter Testing
Main work carrying out by the Central Workshop
  • Running repair and major repairs of Board vehicles.
  • Vehicle periodic services
  • Engine Overhauling
  • Fabrication of package treatment plants
  • Treatment plant repair work
  • Other Fabrication work
  • Repair to all kinds of Pumps, Valves, Compressors, Generators etc.
  • Electrical repair works, including motor rewinding.
  • Electronic equipment repair work.
  • Testing & issuing test reports for Ferrules, Valves, etc.
  • Drivers, Pump Operators competence tests.
  • Installations of plant & equipment.
  • Site breakdown repair.
  • Quality inspections.
  • Water meter testing
  • Water meter repairing


We are a highly skilled crew in Mechanical & Electrical service looking for the opportunity to assist NWSDB in order to achieve a targeted safe drinking water supply in Sri Lanka.

Chief Engineer,

Central Workshop,


Maligawa Road,


T.P- 0112636327

Fax- 0112624738

Contact Details of Staff Members 
                Section            Name        Designation    Telephone      Fax
 Office  (Central Workshop)   Mr.A.L.S.Sriwardhana  Chief Engineer  0112636327 0112624738 
Mrs. Koshila  Accountant  0112636327
Mrs. Shriyani  Staff Assistant  0112636327
Mrs. Dulani  Supply Assistant  0112636327
 Pump Section     Mr.T.B.P. Priyadharshana Snr. Mechanical Engineer  0112636327
 Mr.K.G.L.P.Kumara  E.A.(Mechanical)  0112636327
 Mr.G.J.D.Alwis  E.A.(Mechanical)  0112636327
 Electrical Section    Mr.Nuwan Dayananda  Electrical Engineer  0112636327
 Mrs.N.Hewavitharana  E.A.(Electrical)  0112636327
 Mr.Indika  Store Keeper  0112636327
 Fabrication Section   Mr.T.B.P. Priyadharshana  Snr. Mechanical Engineer  0112636327
 Mr.Suwaris  E.A.(Mechanical)  0112636327
 Vehicle Section      Mr.Thusara Sadakelum  Mechanical Engineer  0112636327
 Mr.H.A.J.Bandara  E.A.(Mechanical)  0112636327
Mr.K.P.C.De Silva   E.A.(Mechanical)  0112636327
Electronics Section Mr. C.M. Karunarathna Snr.Electronics Engineer 0112636327
Mr.N.Sanjeewa E.A.(Electronic) 0112636327
Meter repair Section Mr. Jayaruwan Mechanical Engineer 0112636327
Mr.Namal  Bandara E.A.(Mechanical) 0112636327


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The Head Office of the National Water Supply and Drainage Board is located in Ratmalana. The Head Office overlooks all the island wide operations. A sub office is located about 1 km away at Telawala Road.


The following Divisions / Sections are located in the Head Office.
• Chairman, Vice Chairman and Working Directors Office
• Senior Management (General Manager and Additional General Managers)
• Policy and Strategy Division
• Planning & Designs Division
• Water Supply Projects Division
• Mechanical & Electrical, Energy Services Division
• Information Technology Division
• Development Division
• Tenders & Contracts Division
• Finance Division
• Human Resource Management & Industrial Relations Division
• Commercial Division
• Internal Audit Division
• Corporate Planning Division
• Japanese Projects Unit
• Supplies Section
• Library
• Transport Division
• Sewerage Division
• Publicity Division
• Manpower Development & Training Division
• Research & Development Division
• Rural Water Supply Division
• Ground Water & Investigations Division
• GIS & Mapping Division
• Central Laboratory
• Central Workshop
• Main Stores

The above divisions coordinate and monitor the functions of regional operations.

Contact Details:

Postal Address: Head Office, National Water Supply & Drainage Board, Galle Road, Ratmalana.
General Telephone Nos: 0112611589, 0112612566, 0112637194
General Fax No: 0112636449
Hunting No: 0112638999
(Note: for international direct dialing, please add country +094 instead of leading 0 in all the above numbers)


Location Map:



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