Madei/Mandovi is the largest river in Goa which drains almost all of northern and central Goa with the basin area of 1,580 sq km or 43% of Goa’s total land area. Any tempering with its headwaters will seriously disturb its natural ecology and will damage the ecosystem of the entire river basin in Goa.
The livelihood of 296 villages in the talukas of Tiswadi, Bardez, Bicholim, Sanguem and Ponda depends on the resources of Madei/Mandovi waters. It will also affect the Zuari river basin which is linked with the Mandovi through the Cumbharjua canal.
The Salinity Factor
Tree Frog - Pic by Mohan Pai
As a result of shortage of water staple produce of rice, pulses and cereals may get affected. The plantation crops such as cashew, coconut and arecanut which are largest plantation crops in Goa are bound to suffer. The largest size of cashew plantations are located in the Madei/Mandovi river basin in the talukas of Sattari, Bicholim and Bardez. The area under arecanut is 2,000 hectares and almost half of it is in Ponda taluka.
Other plantation crops grown in Goa are the bamboo, the banana and mango, bhirand or kokum is also an important plantation crop which forms a part of daily diet. It is used as a garnish to give an acidic taste to curries and vegetable as well as in the preparation of cooling kokum syrup during the hot summer months.
The Mandovi estuary is navigable round the year up to about 45 km from the mouth upstream and is one of the two main waterways of Goa mainly used for transporting iron ore barges of capacity 1,000 - 1,500 tons and transported to the Mormugao Port for export. The depth of estuary varies from 8-10 m at the mouth to less than 2 m.
Mouth of the River Mandovi - Barge carrying iron-ore - Pic by Mohan Pai
Fishing is a major industry in Goa and over 40,000 people are dependent on fisheries for their livelihood. Out of 11 talukas of the state, fisherman fro 8 talukas are involved in fishing. Fish curry and rice is a staple food of Goan people.
Fisherwomen of Britona - Pic by Mohan Pai
The inland catch from the rivers was 3,749 tonnes as against the total catch of 73,135 tonnes (2001). There are landing centres for inland fisheries all along the banks of the Mandovi. The reduction in the water level and the deeper ingress of salt water will affect the fishing due to barriers to fish migration and this will reduce the fish catch. The tourism industry in Goa depends on the local fish produce which will definitely face problems.
The mangroves will be also affected and the shellfish breeding will be depleted and the aqua farms along the river banks also will face problems.
Goa’s sandy beaches are major tourist attraction. Goa is an international tourist destination and tourism is the most important component of Goa’s economy providing employment related opportunities to the local population. Tourist arrivals amounted to 2.3 million in 2005 exceeding the local population by almost a million. Number of hotels and resorts, residential dwellings, commercial establishments, beach side entertainment centres/eat outs have changed the landscape of the coastal strip with activities that follow such a coastal tourism.
Tourists at Calangute - Pic by Mohan Pai
The Government has laid special emphasis on creating an attractive image for this international destination by developing infrastructure and diversifying a beach oriented tourism to other forms of tourism such as heritage tourism, eco-tourism, adventure and aqua-sports, etc. And there is an attempt to shift developmental activities towards hinterlands and backwaters as well as the Western Ghat forests in the form of eco-tourism. The other tourist attractions are the wildlife sanctuaries and the waterfalls of Dudhsagar which is a main tourist attraction as well as Surla waterfalls and Vajra Sakhala waterfalls in Chorla Ghat which will be reduced to a trickle due to reduced waters.
Watersports - Northern beaches of Goa - Pic by Mohan Pai
Karnataka’s project with as many as 11 dams to be located within an area of 50 km radius have been planned in an area much prone to earthquakes. Two large dams - Supa reservoir and Codasalli are just 50 and 35 km away respectively from the Mahadayi project area. Since the project area is bordering Goa, Goa will also be very vulnerable for any seismic disturbances.