Spread over an area of 19 lakh sq ft., the Rajiv Gandhi Government General Hospital in Chennai uses about 22.5 lakh litres of water daily. | Photo Credit: B. JOTHI RAMALINGAM

The Public Works Department (PWD) has submitted a proposal to the State government to build sewage and effluent treatment plants at government hospitals in the State to ensure better biomedical waste management practices were adopted.

While the new government hospitals are being designed with STPs, including the 19 district headquarters hospitals and the recently inaugurated Kalaignar Centenary Super Specialty Hospital, Guindy, the older hospitals do not have the facility and largely let out wastewater into sewer network. Estimates are being prepared for creating infrastructure in the existing medical facilities, including in Vellore, said the PWD officials.

The department has prepared an estimate for setting up STPs and ETPs in 13 government hospitals in Chennai at a cost of ₹103.45 crore. For instance, the daily water consumption at the Rajiv Gandhi Government General Hospital, with an area of over 19 lakh sq. ft., was nearly 22.5 lakh litres a day.

“We are planning to construct STP with a capacity to treat 2.25 million litres of sewage a day and ETP of 2.10 kilo litres a day at RGGGH. Now, wastewater in the sewage collection well is linked to the Chennai Metropolitan Water Supply and Sewerage Board’s sewer infrastructure. Similar infrastructure is being planned in other hospitals such as the Government Stanley Hospital,” said an official.

Recycling water

The hospitals were water-intensive establishments and STPs would help conserve freshwater. While a portion of the treated water would be recycled for gardening and other non-potable purposes such as flushing, the remaining quantum would be let into the sewer network or waterways, said K. Ayeratharasu Rajasekharan, Chief Engineer, PWD, Chennai Region.

The new STPs would have the latest membrane bioreactor (MBR) technology as most of the hospitals had space crunch. These STPs would comply with the Central Pollution Control Board’s norms and have less maintenance cost, he said.

On the MBR technology, J.R. Moses, a Chennai-based water expert, said it was a combination of membrane process and biological technology. With an efficient treatment process, the quality of the treated sewage would be better with various parameters like biological oxygen demand reduced to the minimum. It would be compact and save on power by about 15%-20%. Some of the private medical facilities had retrofitted existing STPs with the MBR technology, Mr. Moses added.