Mahoning River Watershed

Mahoning River watershedThe Mahoning River watershed is located in northeastern Ohio. It drains a total of 1,085 square miles in Ohio and flows through all or part of seven counties. Major municipalities partially or fully in the watershed include Youngstown, Warren, Alliance and Lordstown.

The eastern portion of the watershed is predominantly comprised of urban development with some forest and agricultural lands. The western portion of the watershed is a mixture of forest, hay and pasture lands, cultivated crops and urban development.

 

 

 

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Mahoning River (upper) Watershed

Mahoning River (upper) watershedThe upper Mahoning River watershed is located in northeastern Ohio. The upper Mahoning River watershed, which is the area upstream of the confluence of Duck Creek in Leavittsburg, drains approximately 539.8 square miles and is located in Portage, Mahoning, Trumbull, Columbiana, Stark, and Geauga counties. Land use in the upper Mahoning River watershed is a mix of agriculture, rural residential and urban land uses. Significant public reservoirs used for recreation are Berlin Lake, Lake Milton, M.J. Kirwin Reservoir, Deer Creek Reservoir and Dale Walburn Reservoir. The Mahoning River mainstem is a source of public drinking water for the cities of Newton Falls and Sebring; the city of Alliance has a drinking water intake within Deer Creek Reservoir.

 

 

 

 

Monitoring

Ohio EPA sampled water quality in the watershed in 2006. Only 38 percent of the sites on the Mahoning River fully met aquatic life use goals and five percent met recreation use goals. Problems were an excessive amount of fine sediment in the channels and nutrient enrichment from runoff and other drainage from cropland and animal farming, high nutrients in wastewater, substantial habitat degradation associated with dam impoundment and a generally unnatural stream flow regime from the regulated flows caused by the large dam releases. The major sources of the bacteria loading are cropland drainage and home septic systems, with lesser contributions from wastewater systems (both CSOs and WWTPs) and urban runoff.

TMDL Report

The upper Mahoning River Watershed Total Maximum Daily Load (TMDL) report was approved by U.S. EPA on September 28, 2011. TMDL reports identify and evaluate water quality problems in impaired water bodies and propose solutions to bring those waters into attainment with water quality standards.

TMDLs in selected areas of the watershed are calculated for E. coli bacteria, total phosphorus, and sedimentation and habitat. Recommendations include new concentration limits for eight facilities, adoption of conservation practices on cropland, overall better treatment of decentralized waste water, improving habitat through a more natural approach to drainage maintenance and better dam release protocols. The report recommends increased inspections and subsequent enforcement regarding home septic systems that do not comply with local codes and implementing conventional management practices to abate pollutant loading from cropland and urban landscapes.

TMDL Report without Appendices

Supplemental Information

  • TMDL fact sheet
  • Biological and Water Quality Study of the upper Mahoning River and Selected Tributaries, 2006, Columbiana, Mahoning, Portage, Stark and Trumbull Counties, Ohio.

Implementation

The following implementation projects have been completed in the watershed.

Mahoning River (lower) Watershed

Mahoning River (lower) watershedThe Mahoning River (lower) watershed is located in northeastern Ohio on the Ohio-Pennsylvania border.  Youngstown, Warren and Lordstown are major municipalities in the watershed. Youngstown and its surrounding communities are predominant in the central portion of the watershed. Other land uses include pasture and hay lands, forest and cultivated crops. Mosquito Creek Lake and Meander Creek Reservoir are located in this watershed.










Monitoring

The Mahoning River is located in northeast Ohio.  The lower portion of the watershed was studied during 2013.  The Mahoning River flows into the Beaver River in Lawrence County in Pennsylvania.  The Mahoning River (lower) watershed is divided into four subwatersheds, as follows:

  • 05030103 05        Mosquito Creek
  • 05030103 06        Duck Creek-Mahoning River
  • 05030103 07        Meander Creek-Mahoning River
  • 05030103 08        Mill Creek-Mahoning River
  • 05030103 90 01   Mahoning River mainstem

TMDL Report

This TMDL report was developed by U.S. EPA Region 5.  A copy of the U.S. EPA Region 5 posting is provided below.

9/17/2004

Mahoning River, Ohio

This Final Total Maximum Daily Load (TMDL) has been developed for the Mahoning River in Portage, Trumbull and Mahoning Counties in Ohio by the U.S. EPA, Region 5.  Ohio identified segments where the designated use (primary contact/swimmable) of the Mahoning River was impaired by fecal coliform, including Eagle Creek, downstream to Mosquito Creek and Mill Creek, and further downstream to the Pennsylvania border.  Other pollutants are present but the focus of this TMDL is on the fecal coliform impairment.  This TMDL identifies reductions in fecal coliform inputs to meet the primary contact (swimming) recreational use as determined by the State of Ohio.  The public had the opportunity to comment from July 29, 2004 to August 28, 2004 and the comments were taken into consideration for preparation of the final report.

Supplemental Information

Implementation

The following implementation projects have been completed in the watershed.