Assessment of routine operation and maintenance work of a small community water treatment plant in North Guwahati, Assam, India

Abstract

A water treatment plant's efficiency is reliant on its regular maintenance and operation. Many water treatment plants across the world are outsourced to private enterprises for day to day operation and maintenance. However, the impact of outsourcing may not always be profitable as design of faulty treatment units or carrying out improper routine operation and maintenance works by the private enterprise may ultimately affect the quality of potable water produced. The current study aims to evaluate the routine operation and maintenance tasks performed by an outsourced private enterprise at a small community water treatment facility in Assam. The performance monitoring of the treatment plant indicates that the plant is unable to produce potable water meeting national water quality standards. The turbidity of treated water is not able to meet the BIS acceptable limit of 1 NTU but it complies with the BIS permissible limit of 5 NTU. In general, the plant operators lack the skills required to operate the treatment plant effectively. Coagulant dosing is completely based on personal experience of plant operators instead of using jar test results. The backwashing of filter beds is carried out arbitrarily without considering the turbidity of filtered water. These factors have resulted in malfunctioning of the treatment units ultimately affecting the quality of potable water produced from the plant. The skill set of plant operators and chemist has been enhanced with bilingual stepwise instruction charts and on-hand training at the site. This aids in raising the standard of produced potable water. The turbidity of treated water is observed to be close to the BIS acceptable limit of 1 NTU.