U.S. Department of the Interior National Water-Quality Assessment Program- NAWQA U.S. Geological Survey The Allegheny-Monongahela River Basin Fact Sheet

In 1991, the U.S. Geological Survey be conducted at the State and local level Description of Allegheny- (USGS) began a National Water-Quality and will form the foundation on which Monongahela Basin Assessment (NAWQA) program. The national- and regional-level assessments three major objectives of the NAWQA are based. The 60 study units are hydro- The Allegheny River drains about program are to provide a consistent logic systems that include parts of most 11,805 square miles of New York and description of current water-quality major river basins and aquifer systems. Pennsylvania. The Monongahela River conditions for a large part of the Nation's The study-unit areas range from 1,000 to drains about 7,340 square miles of Mary­ water resources, define long-term trends more than 60,000 square miles and land, Pennsylvania, and West Virginia. in water quality, and identify, describe, include about 60 to 70 percent of the The study unit consists of the total and explain the major factors that affect Nation's water use and population served drainage areas (19,145 square miles) of the water-quality conditions and trends. The by public water supplies. Twenty study- Allegheny River and the Monongahela program produces water-quality informa­ unit investigations were started in 1991, River, which join to form the Ohio River at tion that is useful to policy makers and 20 started in 1994, and 20 more are Pittsburgh, Pa. managers at the National, State, and local planned to start in 1997. The Allegheny- levels. Monongahela River Basin was selected to All of the area of the Allegheny- The program will be implemented begin assessment activities as a NAWQA Monongahela basin is included within the through 60 separate investigations of river study unit in 1994. The study team will Appalachian Plateaus Physiographic basins and aquifer systems called study work from the office of the USGS in Pitts­ Province. The area is characterized by units. These study-unit investigations will burgh, Pa. broad, rounded uplands that are highly dissected by numerous valleys. Relief is generally greatest in the southeastern i"l /~H mountainous areas where the valleys are ..' I ^w-V I wide with steep sides and the uplands are broad, linear ridges. The relief is lowest, and valleys and uplands are wide in the northern areas that have been eroded by glacial activity. The land surface is under­ lain by sedimentary rocks (sandstone, shale, coal, and limestone) of Pennsylva- nian, Mississippian, and Devonian age that are fractured and have been faulted and folded in many areas. The bedrock is blanketed by a layer of weathered rock material, and Quaternary glaciofluvial deposits, and alluvium. The weathered rock material is generally thin (less than 20 feet), the glaciofluvial deposits com­ monly range in thickness from 20 to 500 feet, and the alluvium is generally less than 100 feet thick. Soils in areas of steep slope are commonly shallow, weakly developed, poorly drained and have low fertility and high erosion potential. Soils on gentler slopes and soils over unconsoli- dated sediments are commonly deep, well-drained, and fertile. The climate of the study unit is temperate. The average annual temperature is 49 degrees Fahren­ heit Mean monthly temperatures range EXPLANATION from 29 to 72 degrees Fahrenheit. Average annual precipitation is 42 inches and " Study Unit Boundary ranges from 37 inches in northern areas to 60 inches in the southern, mountainous areas. The average annual runoff (1951- 1980) ranges from 25 to 40 inches per year in the mountainous southeastern areas and from 18 to 26 inches elsewhere. The 0 20 40 MILES average annual recharge is estimated to range from 8 to 15 inches. The remainder 0 20 40 KILOMETERS of the average annual precipitation is esti­ mated as evapotranspiration. The 1990 U.S. Census Bureau popula­ Most of the unconsolidated glacioflu- Sedimentation and contamination of surface tion data indicate that approximately vial and alluvial sediments and the water can occur after urban runoff and 4,166,000 people lived in counties that are fractured and folded sedimentary rocks combined stormwater-sewer overflow when wholly or partly within the study unit. are aquifers. Many of the major Quater­ the capacity of waste water treatment facili­ nary aquifers are in buried bedrock ties are exceeded. Nutrients, bacteria, and Most of the population resides in and near turbidity affect water supplies in many Pittsburgh, an urban-suburban area. The valleys. The alluvium sediments are also areas. 1990 population density within a 10-mile excellent sources of ground water in major river valleys. Yields from ground-water Contamination of surface waters and radius of Pittsburgh commonly exceeds ground waters by nutrients and pesticides 5,000 people per square mile, and the flow systems in the fractured rocks are used in agricultural and urban areas can population density is greater than 13,000 difficult to predict, highly variable, and occur where land uses are highly mixed. commonly of local extent. people per square mile in parts of Pitts­ Acidic precipitation affects water quality and burgh. Areas distant from Pittsburgh are In 1990, water withdrawn from aqui­ biological communities. generally rural and the 1990 population fers and surface water in the Allegheny- Naturally occurring radiochemicals, espe­ density is less than 130 people per square Monongahela study unit averaged cially radon, affect the quality of ground- mile except for towns such as Johnstown, 3,531 million gallons per day, most of water supplies. Jamestown, Morgantown, and other which was surface-water withdrawal. The discharge of heated water used for towns near major transportation corri­ Nearly all water supply in, the Pittsburgh cooling thermoelectric power plants dors. Major industries include manu­ area is withdrawn from surface water. adversely affects stream water quality and facturing, coal mining, oil and gas produc­ Withdrawals from surface water were biologic communities and can cause reduc­ tion, construction industry, transportation used for generation of thermoelectric tions in dissolved oxygen concentrations, industries, forestry, agriculture, and power (66 percent of total water with­ algal blooms, and growth of pathogens. outdoor recreation. Forests are the domi­ drawals) and for public supply nant land use. In the 1970's, the most (12 percent of total water withdrawals). Communication and About 19 percent of the total water with­ recent period for which land use/land Coordination cover data is available, the study unit was drawn was for industrial and mining 64 percent forested, 30 percent agricul­ purposes. Only 2 percent of the water Communication and coordination tural land, 4 percent urban land, and 1 withdrawn was from ground water for between USGS personnel and other inter­ percent barren or mined land. The public supply, and about 1 percent of total ested scientists and water-management remaining 1 percent of the area was water withdrawn was for self supplied, organizations are critical components of domestic water supply. Ground water covered by streams, lakes, and wetlands. the NAWQA program. Each of the study- provides the domestic water supply of unit investigations will have a local liaison The Allegheny River begins in almost all rural residents in the study committee consisting of representatives northern Pennsylvania, flows north into area. who have water-resources responsibilities New York, then bends to the south to flow from Federal, State, and local agencies, universities, and the private sector. again through Pennsylvania toward Pitts­ Major Water-Quality Issues burgh. Major tributaries of the Allegheny Specific activities of each liaison River include the Conewango Creek, Major water-quality issues in the study committee will include exchange of infor­ French Creek, Clarion River, Redbank unit are related to the following mation about water-quality issues of Creek, Kiskiminetas River, and Cone- conditions: regional and local interest; identification of sources of data and information; assis­ maugh River. Mean annual flow of the Contamination of surface and ground water tance in the design and scope of project Allegheny River 24 river miles upstream by acidic mine drainage is the most signifi­ products; and review of project planning from the Ohio River is 19,660 cubic feet cant source of water-quality degradation. The quality of more than half of the river documents and reports. The liaison per second. The Monongahela River committee for the Allegheny-Mononga- begins in West Virginia at the confluence reaches in the study unit is degraded. Aban­ doned coal-mined areas are a major source hela River Basin study was formed and of the West Fork River and Tygart Valley of acidic mine drainage. High concentra­ convened in June 1994. River and flows northward to Pittsburgh. tions of acidity, trace metals, sulfate, and Major tributaries of the Monongahela dissolved solids can eliminate aquatic biota. Steven D. McAuley River generally flow northward and Degradation of water quality from oil and include Cheat River, Youghiogheny River, gas production, especially from abandoned Tygart Valley River, and West Fork River. wells and drilling and production sites, Information on technical reports and Mean annual flow of the Monongahela occurs in the upper Allegheny River Basin. hydrologic data related to the NAWQA River 11 miles upstream from the Ohio Brines, methane, trace elements, and program can be obtained from: River is 12,470 cubic feet per second. organic compounds are released to surface Streamflow in much of both river basins is water and ground water. Project Chief, Allegheny-Monongahela controlled by reservoirs. Most of the reser­ River Basin NAWQA Surface-water and ground-water contamina­ U.S. Geological Survey voirs are used for flood control, and some tion by industrial wastes or chemical spills is 1000 Liberty Ave., Room 2204 are used for recreation and water supply, a concern particularly near sources of large Pittsburgh, PA 15222 as well as for control of water quality and water supply near urban areas, along the (412) 644-2707 navigation during low flows. A series of major rivers, and in principal aquifers. Organic compounds and toxic trace Pennsylvania District Chief locks and dams permits navigation over elements from petroleum products, from U.S. Geological Survey about 50 miles of the Allegheny River and storage tanks or pipelines, or from industrial 840 Market St. about 100 miles of the Monongahela sites are a hazard to aquatic biological Lemoyne, PA 17043-1586 River. communities and to water supply. (717) 730-6900

June 1995 FS-137-95