Studies were conducted on water quality, physico-chemical, bacteriological and biological parameters and animal species diversity. The water in the Ganga is regulated through 4 barrages and diverted into three major agricultural canals. Water is also diverted for power projects at Chilla, Rishikesh and the National atomic power station at Narora. The river is subject to large seasonal changes varying from 200 m width in the summer dry season up to 1.5-2 km during the monsoon. The physico-chemical and bacteriological studies revealed increasing amounts of pollution from domestic sewage, sugar factories and chemical industries and tanneries.
Pollution is more severe in the downstream sections.
Mahseer, a valuable game fish, and river otters appear to be negatively impacted. Two species of crocodile were identified, Gavialis gangeticus and Crocodylus palustris . Muggers are captured in fishing nets and natural breeding was recorded, with hatchlings discovered at Narora in October 1993. Large muggers were seen at five localities and a large number of mugger were present in the Ganga agricultural canal. Gharial were also found at four locations in smaller numbers.