DELHI’S WETLAND AUTHORITY ORDERS AGENCIES TO TEST CITY WATER BODIES

NEW DELHI: Delhi’s State Wetland Authority (SWA) has asked all land-owning agencies in the Capital to test samples from water bodies to assess how many fail to meet pollution standards in order to take corrective action.

While it is mandatory to test water samples monthly as per the Central Pollution Control Board’s (CPCB) Guidelines for Restoration of Water Bodies, 2019, such an assessment was last done in Delhi only from March until May 2020, with 115 water bodies then found to be meeting the Class D criterion (propagation of wildlife and fisheries), officials said.

The CPCB has specified different categories for water quality, and allotted Class D to water bodies which require pH (potential of hydrogen) between 6.5 and 8.5, dissolved oxygen (DO) to be 4mg/l or higher and free ammonia to be 1.2mg/l or less – all needed to sustain aquatic life.

The CPCB’s other criteria are Class A (drinking water sources without treatment), Class B (outdoor bathing), Class C (drinking water sources after treatment) and Class E (irrigation, industries and waste disposal).

In a meeting with Delhi’s lieutenant governor Anil Baijal last Thursday, the SWA said that the second such assessment had commenced in Delhi last month, with the Delhi Development Authority (DDA) having tested 44 water bodies so far under its jurisdiction. All of them met the water quality criterion of Class D, officials said. As per CPCB’s indicative guidelines to protect and revive water bodies across the country, water samples need to be collected each month, or at least eight times a year, so states can ascertain the changes in the water quality and their reasons.