CHENNAI: The rejuvenation of Thirumanimutharu river, one of the key tributaries of Cauvery river, are going on in full swing and now the southern zonal bench of National Green Tribunal (NGT) has set April deadline to complete all the works. Continuous discharge of untreated sewage and industrial effluents has made Thirumanimutharu one of six polluted rivers in Tamil Nadu. Central Pollution Control Board (CPCB) has identified 15 km stretch from Salem to Papparapatti has ‘priority-1’ polluted river stretch.
Though State government accorded administrative sanction to implement Under Ground Sewerage Scheme for 421.67 km and construction of four Sewage Treatment Plants (STPs) way back in 2006, the work was going on in snail’s pace due to multiple reasons, including issues in tender process. However, with NGT intervention and State government’s will, the project picked-up pace in last few years. As per the latest status reported submitted by Salem city municipal corporation commissioner R Sadheesh before NGT, the construction of four STPs were undertaken, of which two STP works were completed and partly commissioned and the other two STPs will be put to function by April. The combined capacity of four STPs is 98 MLD, while the work on UGSS is progressing well.
NGT bench, comprising of judicial member Justice K Ramakrishnan and expert member Saibal Dasgupta, has accepted the status report and directed the Salem corporation to complete the works within April. Tamil Nadu Pollution Control Board has been directed to monitor the progress of the works.
Source of pollution
Industries such as sago units, textile dyeing and bleaching units are located along the banks of the Thirumaimutharu river. The Salem corporation sewage is discharged directly into the river. As per the official statistics, there are about 1,078 industries in Salem corporation limits, of which 357 industries generating trade effluent are located in the taluks where the river passes. Following surprise inspections, several illegal units were unearthed when activities were being carried out in residential houses and effluent was discharged into the open sewer line.
Officials said 277 such units were dismantled, electricity was disconnected to 71 unauthorised units and 28 consented units for lack of compliance of pollution norms. The report of analysis of the river water collection at various location as directed by NGT reveals that the Biochemical Oxygen Demand (BOD) levels are very high which shows the presence of high level of fecal coliforms indicating the river gets contaminated due to sewage discharge.
Sewage Treatment Plant status
1. Vellakutttai STP
Capacity: 13 MLD
Remarks: Commissioned and under operation. However, at present, only 1.5 to 2 MLD is being treated. Out of 10,740 house service connections, 3,720 are connected to STP
2. Anaimedu STP
Capacity: 6 MLD
Remarks: Construction completed last May and under operation. Out of 6,552 house connection, 1,080 connected
3. Vandipetti STP
Capacity: 44 MLD
Remarks: Under construction and would be finished by April
4. Mankuttai STP
Capacity: 35 MLD
Remarks: Under construction and would be finished by
April this year