Q ST QUA TAT ALIT US O TY IN OF W N IN WA NDIA ATER A- 2 R ...

CHAPTER VII7.1 Mahi River SystemWater Quality of Rivers in Mahi BasinThe Mahi basin extends over an area of 34,842 sq. km. The interstate river Mahiis 583 km long, originating in Madhya Pradesh, passing through Rajasthan andGujarat and draining into the Gulf of Khambhat. The Mahi flows northwardsinitially entering into Banswara district and then turning southward flowingthrough Udaipur and Dungarpur districts before entering into Gujarat. In Gujarat,it flows through Panchmahal, Kheda, Vadodara and Bharuch districts beforedraining into the Gulf. The principal tributaries of the river are the Som from theright and the Anas and the Panam from the left. The important urban centres inthe watershed of Mahi are Godhra, Vadodara, Dohad and Dadhoi in Gujarat;Ratlam, Jaora in Madhya Pradesh; and Banswara in Rajasthan.Vadodara is a metropolitan city as well as a centre for industrial activity. InVadodara majority of industrial units are pharmaceutical and petrochemicals,besides units of caustic soda; distillery, fertilizer, dyes and pesticides also exist.The wastewater generated by IPCL, GSFC, Gujarat refinery, GIDC, Indian Dyestuff (P) Ltd. are being discharged into the Gulf of Khambhat through theVadodara effluent channel. Although the large Vadodara industrial complex hasextended considerably to the west of the small Dhadhar creek and dischargeslarge quantity of effluent into the tidal segment of the river Mahi, the Dhadhar hasits own independent catchment area (outside Mahi Basin) inclusive of its tinytributary Viswamitri which is extremely polluted by the effluent generated fromVadodara.7.2 Water Quality Monitoring in Mahi BasinThe State Pollution Control Boards of Gujarat and Rajasthan at 17 locations aredoing the water quality monitoring of the River Mahi and several tributaries in thebasin. The monitoring locations are on mainstream of River Mahi (11) andtributaries- Anas (1), Panam (1), Jammer (1), Malei (1), Shivna (1) and Chillar(1). The ranges of water quality observed in River Mahi, Panam and Anas withrespect to Temperature, DO, pH, Conductivity, BOD, Nitrate +Nitrite-N, FaecalColiform and Total Coliform are presented as minimum, maximum and meanvalue to assess the extent of water quality variation throughout the year.7.2.1 Water quality of River Mahi and its tributary streams Shivna, Jammer,Malei, Chillar, Anas and PanamThe water quality of River Mahi is meeting the desired criteria with respect toTotal Coliform and Faecal Coliform. pH is observed in the range of 7.1-9.1 and is81