BOD level at Dhanwapur sewage plant within permissible limit: GMDAUpdated: Dec 04, 2019 20:43 IST
Gurugram: The level of dissolved oxygen in the sewage treated at the 68 MLD plant at Dhanwapur has been brought under control as per the directions of the National Green Tribunal (NGT), the Gurugram Metropolitan Development Authority (GMDA) said on Wednesday.
Sharing details of quality of recycled water at the sewage treatment plant (STP), a GMDA official told HT that biochemical oxygen demand (BOD) level has been brought to below 30 mg/l from 100 mg/l earlier.
According to the official, the BOD is an indicator of pollution level in water. It is the amount of dissolved oxygen needed by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period. Lower BOD means that the quality of water is good.
The official said that the GMDA roped in IIT Roorkee to improve the quality of recycled sewage water which was measured highly polluted by an NGT-appointed team in April this year. The green tribunal had directed the Haryana government to fix the problem on or before December 31 to avoid heavy penalty of ₹5 lakh per STP in a month from January 1 next year.
The GMDA is likely to submit the current measurement at the unit to the Haryana chief secretary office and it will be submitted to the NGT before the deadline. From next year, the NGT team – which comprises officials of central and state pollution control boards – will physically inspect the 68-MLD STP and other units as well located at Dhanwapur and Behrampur.
“We will reduce the BOD level to 20 mg/l and then 10 mg/l in the next three months,” Praveen Kumar, executive engineer, GMDA, said.
However, a CPCB official, on condition of anonymity, said, “The GMDA’s claim to have reduced the BOD level is not reliable. The process the authority is using is outdated and the NGT has already noted that as faulty. Real test of the GMDA will begin from January next year only.”
The city discharges 80 to 100 MLD untreated water to Najafgarh drain that flows into river Yamuna and pollutes its water. The NGT-appointed team from January will also fine the authority ₹10 lakh per drain a month for carrying polluted water during inspection.