The Daman Ganga also called Dawan River is a river in western India. The river's headwaters are on the western slope of the Western Ghats range, and it flows west into the Arabian Sea. The river flows through Maharashtra and Gujarat states, as well as the Union territory of Dadra and Nagar Haveli and Daman and Diu. The industrial towns of Vapi, Dadra and Silvassa lie on the north bank of the river, and the town of Daman occupies both banks of the river's estuary. The major development project on the river is the Daman Ganga Multipurpose project completed which benefits the state of Gujarat and the Union Territory of Dadra Nagar Haveli and Daman and Diu. In 2015, a major river interlinking project involving inter-basin transfer of surplus water from the Daman Ganga called the "Daman Ganga-Pinjal River Linking Project" has been approved for implementation. The two historical forts on either side of the river at Daman, are the Moti Daman on the southern bank and the Nani Daman, on the northern bank.
Geography
The Daman Ganga, also known as Dawan River, rises in the Sahyadri hills close to Ambegaon village in Dindori taluka of Nasik district of Maharashtra State. It raise at an elevation of 950m. The major tributaries of Daman and Vag run a course of and respectively before joining at Matunji to become the Daman Ganga River. Major part of the river lies in Maharashtra. Its total length from source to the Arabian Sea is. Some of major tributaries which originate and flow through the mountainous region of the states of Maharashtra, Gujarat and the Union Territory of Dadra and Nagar Haveli and Daman and Diu are Dawan, Shrimant, Val, Rayate, Lendi, Wagh, Sakartond, Roshni, Dudhni, and Piperiya. As the river joins the sea at Daman, it is named Daman Ganga. At the estuary there is heavy sedimentation and hence the depth of water is shallow. Daman is located on both banks of the river. At the mouth of the river the bar is level bed made of hard sand, except for the North of the North point where the river enters the sea. The river basin, which lies entirely on the western ghats, has a total catchment area of. Catchment area distribution is: In the Nashik district of Maharashtra ; in the Valsad district in Gujarat ; and in the Union territory of Dadra and Nagar Haveli and Daman and Diu it is . The mean annual run off from the catchment is 3,771 MCM. The upstream area of the river is hilly and covered with forest. Rain fall occurs during the monsoon months from June to September with an annual average rainfall incidence of approximately (maximum recorded is reported to be.
Development
Damanganga Reservoir Project
There is an existing major irrigation project on the river called the Damanganga Reservoir Project, which is located near Madhuban village in Dharampur taluka of Valsad district of Gujarat. It is an inter-state multipurpose project of the Govt. of Gujarat and Union Territory of Dadra and Nagar Haveli and Daman and Diu. The storage of this project is shared by the riparian state of Gujarat and Union Territory of DNHDD as the beneficiary region. The total volume of water to be shared is 516.63 MCM discharge of 25,850 cumecs controlled by 10 radial gates each of size . It has earth dams on both its flanks which measures. The composite dam is founded in area with geological formations of amygdaloidalbasalt, porphyritic basalt, dolerite, and agglomerate. At the Full Reservoir level the reservoir water spread is which includes 987 ha of waste land and of agricultural land. Submergence also involved 12 villages completely and 24 villages partially. The Gross Command Area is and the Cultural Command Area of irrigation is on the left and right bank canals network benefiting the states of Gujarat, Dadra & Nager Haveli and Daman. Total length of the canals is with a design discharge of per second in the right bank canal and per second on the left bank canal. Irrigation covers 112 villages in Valsad district, 26 villages in Daman, and 24 villages in Dadra Nagar Haveli. The Project provides 58 million gallons per day for industrial and domestic water needs and also has a small power plant of 2 MW capacity. The cost of the project was shared between the participating states as per the Inter-State Agreement of 1992. The river supplies potable drinking water to Vapi town, industries around the town and 11 villages in Daman from the head works located on the pick up weir on Daman Ganga River.
Daman Ganga-Pinjal River Linking Project
The Government of India's National Water Development Authority has proposed the Daman Ganga-Pinjal River Linking Project linking the Daman Ganga River to the Pinjal reservoir on the Pinjal River to the south, in the Vaitarna basin allowing surplus water from the Daman Ganga to be diverted south to Mumbai via the Pinjal reservoir. The feasibility report was prepared by NWDA in 2004, and in 2010 a tripartite agreement was signed between the Central government and the two state governments of Gujarat and Maharashtra. In January 2015, the project was approved for implementation. Under this project the two reservoirs to be created by building dams are the Bhugad dam on Damanganga River in Gujarat and the Khargihill dam on the Vagh River near Behapada village in Thane in Maharashtra. The reservoirs will be linked by a pressure tunnel of and. The Bhugad-Khargihill and Khargihill-Pinjal tunnel which is totally in the Maharashtra state is a long and diameter tunnel and will transfer the surplus waters to the extent of 909 MCM annually to Mumbai City to supplement the present domestic and industrial water supply system, from the Pinjal reservoir to Greater Mumbai; this part of the project is to be implemented as per plans evolved by the Municipal Corporation of Greater Mumbai and Mumbai Metropolitan Region Development Authority. The dam on the Daman Ganga at Bhugad will be a composite dam of in height and long, to create a gross storage of 426.39 MCM and a live storage of 400.00 MCM. The composite dam on Vagh River at Khargihill is proposed to a maximum height of and in length with have gross storage capacity of 460.79 MCM and live storage of 420.50 MCM. The Pinjal dam on the Pinjal River shall be long and will have gross storage of 413.57 MCM and live storage of 401.55 MCM. The annual water diversion to greater Mumbai will be per second. The implementation of the entire project is planned to be completed over a nine-year period.
River pollution
The Damanganga River downstream of Vapi up to its confluence with the sea is polluted from the effluents emerging from the industrial and domestic wastes of the Vapi town, Silvassa, Daman and Kachigaon. According to the Central Pollution Control Board's report the BOD value recorded at its monitoring station downstream of Kachogaon was a high of 30 mgl per liter. According to a study report of the Machhimar Adhikar Rahstriya Abhiyan due to the industrial effluents from the Vapi town the dissolved oxygen level is very low ar 0.1-mg/1 and Mercury content in the groundwater in the town is about ninety six times higher than the standards prescribed by the World Health Organization. Untreated effluents are directly discharged into the Damanganga and Kolak Rivers. This has resulted in pollution of the sea water to a limit of five nautical miles seriously affecting fish life. The Common Effluent Treatment was also reported to be dis-functional with about 1000 small-scale and artisanal fishers in four to five villages getting affected on account of the Sarigam Industrial Association's effluent disposal pipeline.
