Mausam river restoration project


Mausam, Malegaon river restoration project


The industry in Malegaon was producing effluent with following characteristics:

  1. pH :               13
  2. COD :               3000 ppm

The industry was spending close to Rs.2 Cr per annum in neutralizing their effluent from pH – 13 to pH-8. Owing to the presence of Poly Vinyl Alcohol (PVA) in the industry’s effluent, the Activated sludge process based ETP was not working smoothly and continuously getting disturbed and due to this effluent with High COD and BOD was being directly discharged in into the River on frequent basis which was causing environment damage.


The objectives of the project:

  1. Correct the industry’s effluent’s pH from 13 to 8 automatically without chemicals
  2. Reduce the effluent’s COD to less than 300 ppm

Mausam River – Malegaon
India’s first successful river bio-remediation exercise with 90% reduction in contamination levels and results visible over 10 km stretch.

Malegaon is a small city near Nasik in Maharashtra with a population of a little over 500,000. There is no Sewage Treatment Plant in the city, owing to which, the entire untreated sewage of 75 MLD is drained directly into the River Mausam. There is one large industrial unit there in Malegaon which is engaged in bleaching and mercerizing of gray fabric. Semi-treated, industrial effluent of 1.5 MLD capacity is drained directly into the River Mausam.
River Mausam is a seasonal river flowing through the heart of the city of Malegaon. Owing to a barrage just before the River enters the city, the river almost has no fresh water except during the rainy season.
After flowing for almost 10 – 12 kms through the entire city of Malegaon, the river Mausam merges into the River Girna, which eventually merges into the River Tapi.

  1. Dyane Bridge (with just industrial effluent and no sewage)
  2. Mausam Bridge (after sewage entry)
  3. Chandanpuri Bridge (10 kms downstream of inoculation point, after meeting River Girna)

Before any treatment, The Report of waste water parameters of Mausam River are as below



  1. Bio-remediate the portion of the river flowing in front of the industry so that aesthetics improve, the smell reduces and locals stop complaining.


PERC setup a phycoremediation plant for treating the industry’s effluent. The pH was corrected without chemicals to 8, saving Rs. 1.25 cr per year for the industry. The COD was reduced to less than 300 ppm.
The phycoremediation plant doubled up as an algal inoculum manufacturing setup.  The micro-algae harvested was stabilized and added to beneficial, organism specific, organic micro-nutrients and then let out into the river.
The following changes were observed in the river after 3 weeks of treatment.
Apart from the above quantitative parameters which improved significantly, there was a significant drop in smell in the entire city.


Mausam river before and after treatment

Following is the map of river and location of samples collected.

The way forward
The initiative was a huge success. Its impact is visible in an entire city of 500,000. The initiative directly impacts the Bottom of the Pyramid population, several of whom are dependent on the river for their bathing/washing needs. The initiative also provides a template for the National Mission for Clean Ganga and other such river bio-remediation activities.