Treated sewage water for construction: Karnataka pollution board approaches BIS to fix parameters

“Cement on coming in contact with water hardens. We have applied the treated water on cement and found no difference, not even 5 per cent as far as the strength is concerned,” Khaja said.

“When we talk about the usage of treated sewage water in the construction sector, a lot of things like compressive and tensile strengths have to be considered. So setting standards is very important,” he said.

Tensile strength is the resistance of a material to breaking under tension, while compressive strength is the capacity of a concrete to withstand loads from either sides.

In India, IS 456:2000 talks about the standards of water that need to be there for the construction purpose but there is no mention of treated water.

“In the early 1980s and 1990s there was no mention of treated water. In fact during the course of the study with IISc we learnt that nowhere in the world the standards for the usage of treated water in construction have been drawn. So we are done with the study and the communication with BIS has started. We hope that by next World Environment Day on June 5, 2023 we have the standards ready for this,” the officer explained.

He further said that the BIS would also look into the factors of the impact of treated water on the construction workers’ health.

“We have also looked into the factors like after the completion of the construction of buildings things should not start coming out of the wall. The health impact of the treated wastewater on the building workers will also be looked into,” he said.

As part of discouraging the use of groundwater and water from other natural sources, the Bengaluru’s civic body, the Bruhat Bengaluru Mahanagara Palike (BBMP), in 2019 made it mandatory for builders to use treated sewage water for construction purposes in the city.