CHARLESTON (AP) — West Virginia is working with five other states and the federal government to clean up about 475 miles of the Ohio River that is sometimes unfit for swimming because of sewage.

An analysis of more than 14,000 samples taken from Pittsburgh to Cairo, Ill., revealed high fecal counts following heavy rains along almost half of the 981-mile river. The study was conducted by the Ohio River Valley Water Sanitation Commission.

According to the study, much of the sewage is coming from treatment-plant overflows, groundwater runoff from farms and slaughterhouses, and tanning, pulp and paper factories.

The commission is working with the U.S. Environmental Protection Agency and Illinois, Indiana, Kentucky, Ohio, Pennsylvania and West Virginia to develop a remediation plan.

Public hearings are scheduled next month in all six states.