Key Issues

• Nonpoint source pollution from urban runoff, agricultural activities, and abandoned mines is a major cause of water pollution in the Ohio River.
• Dioxin: The upper two-thirds of the Ohio River, from its headwaters in Pittsburgh to Cannelton, Indiana (river mile 720), have been studied extensively for the extent and severity of dioxin contamination. Dioxin levels exceed water quality standards in Pittsburgh and decrease in concentration in a downstream direction, with an increase at Marietta, Ohio, and again where the Kanawha River meets the Ohio. Studies have also pinpointed elevated levels of bacteria from such sources as combined sewer overflows (CSOs) (Combined sewer overflows occur in older cities with “combined sewer systems,” where the sewer system collects both storm water runoff and sanitary sewage in the same pipe. During rainfall or snowmelt, volume in the combined sewer system can exceed capacity, resulting in direct discharges to streams, rivers, lakes or estuaries. These overflows contain not only storm water, but untreated human and industrial waste, toxic materials and debris).
• Acid Mine Drainage: Historically, the Three Rivers Area/Monongahela River Watershed was a leading industrial region for coal mining, resource extraction, boat building and metals manufacturing. Early European settlers recognized the importance of river transport and utilized the area for trade. A leading cause of contamination in both the Allegheny and the Monongahela is from acid mine drainage (AMD), which contributes to the degradation of water quality and biological conditions. Mine drainage waters can be low in pH and high in acidity and metals such as iron and aluminum. AMD has degraded thousands of miles of streams in the region. In addition to abandoned coal mines, abandoned oil wells in the region affect water quality as trace elements leach into surface water and ground water.
• Growth and Urbanization: The area has also witnessed increased growth and urbanization, which has contributed to sedimentation rates, turbidity, nutrient levels and increased urban runoff. Another issue related to the industrial history of the area is the discharge of heated waters from facilities that impact aquatic communities and water quality. Restoration projects in the region have focused on wetlands and AMD as well as trout habitat improvements and the reintroduction of otters and paddlefish.
• Fish Tissue Contaminants
  Because many people eat their catch from the Ohio River, the Ohio River Valley Water Sanitation Commission collects fish and examines the tissue for the presence of certain chemicals that may be harmful when eaten by humans. Yearly results are sent to the states bordering the River. If necessary, states will issue “consumption” advisories, which place limits on the type and amount of fish that can safely be eaten.
• The region also supports a wide variety of recreational activities, habitats and natural resources. Improvements in mainstem Ohio River water quality over the past 40 years have provided a cleaner river for aquatic life.