of this district is about 350,397. The study area is located at the northern part of Bangladesh and situated between N and E. Thousands of villages, towns and commercial places like Shibganj, Mohasthangarh, Bogra and Sherpur have been built on both sides of the Korotoa along its 200-km path. Mohasthangarh, the capital of ancient Pundranagar, is still there beside the Korotoa as a witness of history in Bangladesh. Agriculture, aquaculture and fishing are the primary activities of the people living besides this river. This river receives domestic raw sewage, household waste, and industrial waste from surrounding habitation. During the last decades, natural and human activities have caused a complete deterioration of the river ecosystems.