Ganges Basin (112,490 km²), West Bengal (71,485 km²), Haryana (34,341 km²), Himachal Pradesh (4,317 km²) , Delhi, Arunachal pradesh(1,484 km²), the whole of Bangladesh, Nepal and Bhutan. Several tributaries rise inside Tibet before flowing south through Nepal. The basin has a population of more than 500 million, making it the most populated river basin in the world. The basin comprises semi-arid valleys in the rain shadow north of the Himalaya, densely forested mountains south of the highest ranges, the scrubby Shiwalik foothills and the fertile Gangetic Plains. Central highlands south of the Gangetic Plain have plateaus, hills and mountains intersected by valleys
Choluteca river basin in the urban areas that the Choluteca River basin serves, excessive use and lack of treatment is expected to increase the rate of environmental degradation. Adding to the risk, untreated industrial wastewater originating in Tegucigalpa is discharged directly into the Choluteca. These problems along with sewage that drains into the Choluteca River as it crosses the city signal an urgent need for rehabilitation to mitigate some of the growing water quality risks. According to the Global Climate Risk Index 4 constructed for the period between 1997 and 2006, Honduras is the most vulnerable country in the world to the potential