BWSSB’s trunk sewers set for a major revamp

BWSSB’s trunk sewers set for a major revamp

There’ll Be No More Backflow; Manholes Will Not Overflow

Jayashree Nandi & Aarthi R | TNN


Bangalore: Leaking manholes spreading an unbearable stink and sewage water gushing into homes. How often have you dealt with these problems? There’s some relief in the pipeline, though it may be another two years before it’s all in place.
The BWSSB is all set to start work on the systematic rehabilitation of trunk sewer lines in the city. Work on two of the six packages in this project is expected to begin in June. Tenders for all packages have been floated and two — at Hebbal valley and Challaghatta valley — are close to being finalized.
The Rs 176.12-crore project will rehabilitate the 240-km trunk sewer network across the city. Nearly 30 km of this network will be improved under the first two packages. This includes 12 km of outfall sewers in Hebbal valley and the rest in Challaghatta valley.
These trunk sewers are over 30 years old — their walls fast corroding due to toxic fumes emitted by the sewage. These sewers, which connect the lateral pipelines to the main sewers, form only a small part of the 5,000-km network. With the city fast expanding, there is an urgent need to enhance it further to handle the population explosion.
“The increasing cases of sewage water backflow into houses and overflowing manholes by the roadside are due to overloaded trunk sewers,’’ explains BWSSB chairman P B Ramamurthy. Under normal circumstances, manholes are not supposed to overflow. It happens when they’re either blocked by solid waste like leftover meat, plastic bags and sanitary napkins, or when the sewage is beyond capacity.
Many areas have already borne the brunt of this. Recently, many houses in Krishnappa Garden in Tilaknagar endured overflowing sewage water for over a month. Even houses in upscale areas like Vittal Mallaya Road haven’t been spared from the sewage backflow.
PACKAGE DEAL
Trunk sewers They connect two or more lateral systems Lead sewage to Sewage Treatment Plants Currently, the trunk sewer network is 240 km
Approved package cost (Rs cr) per valley Hebbal: 17 Challaghatta: 21.39 Vrishabhavathi: 29.2 Koramangala Sports Complex to K&C Valley STP: 41.92 Koramangala: 35.4 Kathriguppe, Tavarekere & Arkavathy: 31.21 Total: 176.12