The Narmada Control Authority, which reports to the central government, has said the partially-completed dam's height can be increased by 17 metres to achieve its final height.
Gujarat Chief Minister Anandiben in a tweet thanked the Prime Minister who governed Gujarat for 13 years before taking over the country's top job last month. "Heartfelt gratitude from the people of Gujarat to Hon PM Narendra Modi. The decision pending has come so swiftly. Achchhe din aa Gaye hain!!" said Anandiben. The Gujarat government says the increased height of the dam will help farmers in a state where the monsoon is frequently deficient.
Activists say that the biggest beneficiaries of today's clearance are Rajasthan and Gujarat, both states which are governed by the PM's party.
The Sardar Sarovar Dam is the biggest in a massive hydro-power project in western India, which, supporters say, will benefit farmers and bring water and hydro-electricity to areas in desperate need. But activists like Ms Patkar say the environmental and social toll of the project is unacceptable. "The decision has not been taken in a democratic manner. The government has not consulted the ministries concerned," Ms Patkar, 59, told reporters in Mumbai.
Ms Patkar has been demanding through her protests and fasts that the government abide by a Supreme Court order banning construction to raise the height of the Sardar Sarovar dam until tens of thousands of villagers are resettled and given cultivable land.
The Narmada project consists of about 3,000 dams along the Narmada river and its tributaries in Madhya Pradesh, Gujarat and Maharashtra.