Nasapakkam Sewage Treatment Plant - Chennai, Tamil Nadu

 

Project Overview

Porur Lake in Chennai where 10 MLD tertiary treated water from Nasapakkam plant is discharged • On 15 April 2024, the lake recorded zero mcft water storage compared to 687.40 mcft the previous year (capacity: 1,465 mcft). • Other reservoirs like Poondi (1,323/3,231 mcft in 2023) and Cholavaram (216/1,081 mcft in 2023) also show declining levels.

Nasapakkam Project

Inlet point from where the tertiary treated water from Nasapakkam plant is discharged into the Porur Lake • A 10 MLD tertiary treatment unit built for ₹47.24 crore. • Treated water is sent to Porur Lake (capacity: 70 mcft) via a 5 km pipeline. • Blended Water for Drinking: • Porur Lake supplies water blended in a 1:100 ratio to a 6 MLD Drinking Water Treatment Plant (commissioned in 2023, ~1 km away). • Ensures treated water meets quality standards before city supply.

Perungudi Initiative

A 10 MLD tertiary treatment plant is being constructed, showcasing an innovative model of converting sewage into drinking water.

Limited Reuse Potential

• High cost of tertiary treatment restricts reuse to industries (e.g., Naspakkam lake revival project by CMWSSB). • Scaling plans to 260 MLD tertiary reuse by 2024 were delayed.

Need for Decentralized and Cost-Effective Solutions

• Promote secondary treated water reuse for groundwater recharge through tanks, lakes, and water bodies. • Decentralized treatment is more feasible for coastal cities like Chennai due to slope and terrain constraints.

Policy Gaps

• No clear action plan or timeline to meet 20% reuse of sewage, as mandated by the Ministry of Urban Development. • State policy should prioritize equitable reuse, focusing on drinking water supply, aquifer recharge, and agriculture.

Contact Details

Department