MPCB claims Mumbai’s coastal, river water quality got better
MPCB officials attributed the improvement in the quality to regular checks on waste disposal in water, vigilance of different authorities and the board’s plan to reduce desilting and slum encroachments.Updated: Dec 23, 2018 00:08 IST
The quality of water along the city coast and in Mithi River has improved, the Maharashtra Pollution Control Board (MPCB) has claimed in its year-end report. The report documents quality of coastal and river water in Mumbai after the monsoon.
MPCB officials attributed the improvement in the quality to regular checks on waste disposal in water, vigilance of different authorities and the board’s plan to reduce desilting and slum encroachments.
According to the report, apart from the water off Shivaji Park coast in Dadar — which measured ‘bad’ or ‘polluted’ on the water quality index (WQI) — other areas, including Versova, Juhu, Nariman Point, Malabar Hill, Girgaum Chowpatty, Haji Ali and Worli Sea Face, recorded WQI levels in the ‘medium’ to ‘good’ category or had ‘non-polluted’ status. WQI provides a single number (grade) to show overall water quality of a sample based on several parameters.
While the water quality of Mithi river was in the ‘bad’ category, pollution levels decreased as it recorded an overall decline in the level of biochemcial oxygen demand (BOD) —the level of oxygen that aquatic life needs for survival. MPCB said BOD levels fell from 80 milligram per litre (mg/L) in April 2018 to 40 mg/L post monsoon for Mithi. The safe standard of BOD according to the Central Pollution Control Board (CPCB) is 10mg/L. An affidavit submitted by MPCB in the Bombay high court earlier this year stated that BOD levels for Mithi were 250 mg/L.
Apart from Versova and Nariman Point (12 mg/L), coastal water at other places recorded BOD levels below 10 mg/L. MPCB claimed that pre-monsoon BOD levels for coastal waters ranged from 40- 50 mg/L. As per CPCB, a BOD level above 6 mg/L is harmful for aquatic life and levels above 3 mg/L make the water unfit for human consumption.
“Our post-monsoon analysis was done by collecting samples 15m offshore for coastal water quality and in areas where there was more dilution along Mithi. A marked improvement in water quality has been recorded,” said YB Sontakke, joint director (water quality), MPCB. However, environmentalists rubbished MPCB’s findings. “By fudging data, MPCB is trying to escape accountability. BMC is also at fault for not constructing sewage treatment plants,” said Stalin D, director, Vanashakti, petitioner in the SC matter on Mithi. Sonatke however said MPCB has been levying heavy penalties on non-compliance of sewage water treatment at source. “The state is implementing an action plan prepared by us, which increased desilting activities, reduced direct waste dumping, removed slum encroachments and made citizens aware.”
MPCB findings watered down: Experts
Environmentalists and petitioners in on-going court cases on high pollution levels in city’s river and coastal water have rubbished the state pollution board’s claim that there has been an overall improvement in water quality across the city.
However, the Maharashtra Pollution Control Board (MPCB) said the quality of coastal and river in Mumbai improved within a span of a few months because of the efforts of the state and awareness among citizens. The details come three weeks after HT reported that as per a 243-page report to the Supreme Court (SC) from the state, the deadly floods of July 2005 could occur again, owing to the high pollution levels in Mithi river.
MPCB said restoration of Mithi was 70% done and the remaining work would take six months. “The Mumbai Metropolitan Region Development Authority (MMRDA) and the civicbody have worked a lot to improve Mithi,” said YB Sontakke, joint director (water quality), MPCB, adding, “They have built bridges in areas where excess littering was identified, planned for proper dredging system, and sewage meeting the river is being diverted to newly planned sewage treatment plants (STPs). Both agencies have already spent more than ₹400 crore. We are satisfied with developments.”
However, water quality expert and member of the committee constituted as per SC orders, professor AD Sawant said MPCB findings were incorrect and it was impossible for such a drastic improvement. “The amount of domestic waste entering the Mithi river and coastal areas has not reduced at all. We surveyed these locations earlier this year. The level of BOD is way above 200 milligram per litre (mg/L) and above 100mg/L for coastal areas. As these readings will be submitted to the central pollution board and for future court cases, we need to question the analysis.”
A senior civic official however said all directions as per MPCB’s action to plan to improve water quality were being followed. “We can’t say whether water quality has improved. However, the amount of sewage entering rivers and coastal areas has reduced. With the construction of a Powai STP, encroachment removal work, and setting up of trash booms, a lot of work is being done to address pollution.”
Advocate Shehzad Naqvi, petitioner in a Bombay HC case regarding coastal water pollution, said the state environment department had submitted an affidavit earlier this month indicating that sewage weighing 655 million litres per day enters the sea directly. HT has a copy of the affidavit. “The state environment department told the HC that BMC is not effectively addressing the water pollution issue as STPs are missing and pipes from slum washrooms discharge waste into rivers, creeks and the sea.”
First Published: Dec 23, 2018 00:08 IST