G. D. Agrawal, also known as Swami Gyan Swaroop Sanand, was an Indian environmental engineer, professor, and Hindu monk renowned for his relentless activism concerning the conservation of the Ganges River. Born in 1932, Agrawal graduated from the University of Roorkee (now IIT Roorkee) and later earned a PhD in environmental engineering from the University of California, Berkeley. He dedicated a significant portion of his professional life to academia, teaching at IIT Kanpur, where he championed the cause of environmental protection within the engineering curriculum.

Beyond academia, Agrawal's concern for the deteriorating health of the Ganges River led him to adopt the life of a sannyasi (Hindu monk) and take the name Swami Gyan Swaroop Sanand. His activism involved numerous hunger strikes and public campaigns aimed at pressuring the Indian government to take concrete steps to preserve the river's natural flow and purity. He vehemently opposed the construction of dams and hydroelectric projects on the Ganges and its tributaries, arguing that these projects severely disrupted the river's ecosystem and threatened the livelihoods of millions who depend on it.

Agrawal's unwavering commitment to the Ganges made him a prominent figure in India's environmental movement. He used his scientific expertise and spiritual authority to raise awareness about the ecological challenges facing the river. His hunger strikes, often undertaken at advanced age and in frail health, garnered national attention and put immense pressure on authorities to address his concerns. He ultimately passed away in 2018 after a prolonged fast, his death sparking widespread grief and renewed calls for action to protect the Ganges. His legacy continues to inspire environmental activists and underscores the critical need for sustainable development practices that prioritize ecological preservation.