Pavana River enters ‘priority 1’ category due to increase in pollution

Due to an increase in Biochemical Oxygen Demand (BOD), the Pavana River – a prominent source of drinking water for the twin city of Pimpri-Chinchwad – has entered ‘priority 1’ or most polluted category of rivers/river stretches as per the guidelines of the Central Pollution Control Board (CPCB). Earlier, the river was less polluted and had been categorised as priority 2 by the CPCB.

Based on the pollution level, the CPCB has prioritised river stretches across India into five categories. While priority 1 category river stretches are considered as the most polluted stretches, and the board has directed the state pollution control boards as well as concerned local authorities to take immediate measures to curb pollution levels. Priority 5 category river stretches are considered as comparatively cleaner stretches and do not require attention.

The recent water sample testing conducted by the Maharashtra Pollution Control Board (MPCB) between November 2023 and January 2024 revealed the BOD level in the Pavana River to be above 30 mg/L, indicating a higher degree of pollution, necessitating the river’s entry into the priority 1 category.

Manchak Jadhav, sub-regional officer, MPCB Pune, said, “The board conducts water sample testing every month. For this, we collect the samples from different locations which are pre-decided. In our recent sample testing, we found that an increased BOD level which was showing above 30 mg/L. This indicates that the natural oxygen level in the water has decreased, which helps in processing the organic waste in the water. The current level is significantly high and hence, the river has entered the priority 1 category which requires urgent attention.’’

The Pavana River has been classified into four stretches encompassing Pimprigaon, Chinchwadgaon, Ravet and Sangavi. In 2022, the BOD of the Pavana River at Pimprigaon was recorded between 4.8 and 15.9 mg/L and the water quality index was above 60.

In 2023, the BOD was recorded below 20 till the month of October. In November 2023, the BOD was recorded as 27 mg/L and from December onwards, it was constantly recorded as 31 mg/L with a WQI of 46 and 41, respectively, indicating poor quality of water. In Chinchwadgaon, the BOD level was below 20 mg/L till March 2023. Thereafter, the BOD has been constantly above 20 mg/L. Ravet too recorded a higher BOD level between 15 and 28 mg/L throughout the year. A similar condition was observed in the Sangavi area and from December 2023, this BOD level rose further to 30 mg/L.

Increased urbanisation, inadequate infrastructure for sewage water treatment, and mixing of untreated sewage with river water are responsible for the pollution in rivers across Pune. Time and again, the board has issued directives to local bodies to expand the STP network and increase the capacity for sewage treatment. The board has also penalised the civic authorities for delays and negligence.