Glen Echo Stream, Walhalla Run, Turkey Run, and Adena Brook. About 49.5% of the surface area of this sub-watershed is impervious. The Olentangy River Wetland Research Park, run by Ohio State University--one of the most successful created wetlands in the country--is located in the southern end of this section adjacent to Union Cemetary.
EPA water quality assessments are based on the chemical, physical, and biological integrity of the river. The river has been categorized under ‘non-attainment’ due to excessive nutrient and pathogen loading and elevated stream discharge. Also, the CSO/SSO discharges and the urban runoff are the prime source of pollutant that is leading to the impairment of the river water. Flow would recommend stormwater infiltration and riparian habitat restoration with the help of public support and involving Human Health Department. Riparian corridors serve as a buffer and a filter for water before it reaches the river.
The Clintonville section of the river has been home to many successful restoration projects. A large scale river cleanup effort in Clinton Park in 2005 resulted in several tons of waste being pulled out of the riparian habitat.