Exceeding total coliform levels detected at Pathalam bund stretch of Periyar

Faecal contamination has exceeded the maximum permissible limits along the Pathalam bund stretch of the Periyar River in Ernakulam.

The total coliform count recorded near the bund was 2600 MPN (most probable number) per 100 ml in the samples collected on August 5, 2025, according to the test results compiled by the Kerala State Pollution Control Board. The maximum permissible limit of total coliform in bathing water, as prescribed by the Central Pollution Control Board (CPCB), is less than 2,500 MPN per 100 ml.

In July, the total coliform count in the Pathalam bund stretch was 2400 MPN/100 ml. The faecal contamination showed an increase in August compared to the levels recorded in July 2025.

The board said in its monthly progress report on the Periyar River Action Plan for August 2025 that steps had been taken to maintain the minimum flow in the river during the lean period and to ensure the periodical operation of regulators along the river, including the regulator-cum-bridge at Pathalam.

The minimum flow has been ensured to avoid the presence of high-organic-load sludge that had built up in the river’s upstream stagnant water due to prolonged closure of the shutters and industrial waste.

The report said that the shutters are being operated as required as part of the water management. A protocol for shutter operation has been prepared and submitted to the Chief Engineer of the Department of Irrigation for approval.

The board officials have been sharing the Dissolved Oxygen (DO) levels in the official WhatsApp group formed for monitoring the operation of the regulator-cum-bridges. It has been observed that the DO level near Pathalam regulator-cum-bridge is satisfactory, it said.