What a Chennai-based activist found when Buckingham Canal water sample was tested

CHENNAI: Once a major navigable waterway with clean water crisscrossing the city, the Buckingham Canal will have to wait several years to see its past glory restored as the Tamil Nadu Pollution Control Board (TNPCB), which is the environment watchdog with ultimate powers to act against polluters, awaits Chennai Rivers Restoration Trust (CRRT) to clean up the canal.

Samples of water collected from the canal by O Unnikrishnan, a social activist, revealed that the fecal coliform level in the canal exceeds the permissible limit by several times. As per an NGT (National Green Tribunal) order issued in April 2019, fecal coliform should be below 230 MPN/100ml (most probable number per 100 ml). However, the samples showed 1,600 MPN/100 ml.

Moreover, the BOD (biological oxygen demand) and COD (chemical oxygen demand) were found to be at 123 mg/l and 516 mg/l as against the standard 10 mg/l and 50 mg/l, respectively. Also, the total suspended solids (TSS), at 1,806 mg/l, exceeded the prescribed limit of 20 mg/l.

In a representation to the Water Resources Department (WRD), the TNPCB and Greater Chennai Corporation, Unnikrishnan pointed out that the zonal health officer of Greater Chennai Corporation in Adyar has confirmed mosquito breeding in the stagnant Buckingham Canal. "Please note that the original depth of the Buckingham Canal is 6 feet below sea level and now the depth due to pollution by stagnant sewage waste and garbage is 3 feet above sea level," he said.

Suggesting that the representation should be treated as intimation under Section (9) (1) of the Environment (Protection) Act, 1986, he urged the department to ensure that the discharge of treated sewage into the canal does not exceed the standards set by the NGT.

While TNPCB chairperson M Jayanthi remained unavailable for comments, another TNPCB official said the CRRT will take up the restoration of the canal and a detailed project report (DPR) for the same is being prepared.

Under the project, sewage treatment plants (STP), modular STPs and underground sewer lines will be provided in unserved areas to arrest sewage entering waterways.

The state government has sanctioned Rs 1,281.88 crore for the restoration of the Buckingham Canal and its associated drains and major drains of Adyar and Cooum rivers.

A few months ago, TNPCB informed the NGT that Adyar water near the Adyar Eco-Park is septic, with 1,026 MPN of fecal coliform per 100ml of water, which is lesser than the fecal coliform found in Buckingham – suggesting that the canal is more polluted than Adyar.