Study Unit Description
Surface Water
Great and Little Miami River Basins
The Great and Little Miami River Basins drain approximately 7,350 miČ (square miles) of southwestern Ohio (80 percent) and southeastern Indiana (20 percent). Principal streams include the Great Miami River (4,124 miČ), and Little Miami River (1,756 miČ) in Ohio and the Whitewater River (1,474 miČ) in Indiana. Drainage is toward the south-southwest; all streams in the watershed ultimately drain into the Ohio River. Major tributaries of the Great Miami River include the Stillwater River (676 miČ) and the Mad River (657 miČ), both of which join the Great Miami River at Dayton, Ohio.
Rivers originate in the upper reaches of the basins in agricultural areas consisting of rolling hills and steep-walled but shallow valleys. Large streams are usually underlain by buried valleys filled with sand and gravel deposited by glacial meltwaters. A significant component of baseflow in some streams is provided by ground-water discharge from glacial and shallow bedrock aquifers. The area contains many lakes and small reservoirs that are used for flood control, water supply, and recreation. The largest water bodies in the study unit are Brookville Lake (8.2 miČ) near Brookville, Indiana and Indian Lake (8.0 miČ) near Russells Point, Ohio; Indian Lake was constructed in 1851 to supply water to the Miami-Erie Canal System.
White River Basin
The White River Basin drains 11,349 miČ (square miles) of central and southern Indiana and joins the Wabash River in southwestern Indiana. Most of the Basin is divided into two nearly equal subbasins the East Fork White River and the White River (locally called the west fork of the White River. East Fork White River drains 5,746 miČ and joins the White River at River mile 49.5 near Petersburg, Indiana. The White River, upstream from the confluence with the East Fork White River drains 5,372 miČ. Only 2 percent of the total drainage area (231 miČ) of the White River Basin is below the confluence of the East Fork White and White Rivers. Major tributaries of the East Fork White River include the Driftwood River (1,165 miČ), the Flatrock River (542 miČ), the Muscatatuck River (1,142 miČ), and Salt Creek (636 miČ). The only major tributary in the White River greater than 500 miČ is the Eel River (1,208 miČ).
Both the White River and the East Fork White River originate in the upper reaches of the Basin in agricultural areas consisting of flat to rolling glacial till plain that covers the northern part of the basin. Streams in the northern part of the White River Basin drain relatively flat areas of thick glacial deposits and tend to have more sustained flow. The southern streams drain more steeply sloping areas that lack or have thin glacial deposits and tend to have less sustained flow. Hill and valley landscapes in the southern half of the basin are scenic and most state and federal parks, forests, and wildlife refuges in the basin are located this area. Several reservoirs, originally built for flood control or continuous water supply, are adjacent to State-owned recreation areas. The largest water bodies in the basin include Monroe Reservoir (430 miČ), Geist Reservoir (215 miČ), Morse Reservoir (214 miČ), and Eagle Creek Reservoir (162 miČ).
Population and Land Use
Great and Little Miami River Basins
An estimated 2.8 million people lived in the study unit in 1995. Major cities (population greater than 100,000) in the study unit are Cincinnati and Dayton, Ohio. Approximately 79 percent of the total land area is used for agricultural activities, primarily row-crop production of corn, soybeans, and alfalfa. Residential, commercial, and industrial land uses comprise 13 percent of the area whereas the remaining area consists of forests (7 percent) and water bodies or wetlands (1 percent). Major industries, which are concentrated along the Dayton- Cincinnati corridor, produce automobile parts, business and computer equipment, chemicals, household goods, paper products, and processed foods and beverages. Streams and lakes in the study unit are heavily used by residents for boating, fishing, and other outdoor recreation.
White River Basin
In 1990, the population of the White River Basin was approximately 2.1 million. Major cities include Indianapolis, Muncie, Anderson, and Columbus. The Indianapolis Metropolitan area comprised approximately 65% of the total population. More than 80 percent of the agricultural land is used for crop production, primarily corn, soybeans, and winter wheat. In 1990, the population of the White River Basin was approximately 2.1 million. Most industry is located near large urban areas. Major industries include, primary metal processing, transportation-equipment manufacturing, electrical equipment manufacturing, and heavy machinery production. Most of the population and the industry is located on the west fork of the White River. Residents use the streams and lakes in the Basin for boating, fishing, and other outdoor recreation.
Physiology and Climate
Great and Little Miami River Basins
The Great and Little Miami River Basins are in the Till Plains section of the Central Lowlands Physiographic Province. Glaciation and subsequent erosion produced a flat to gently rolling land surface that is cut by steep-walled river valleys of low to moderate relief. In the southernmost areas, glacial cover is thin and erosion of the less resistant shales has produced a more dissected, hilly terrain of higher stream density. The regional topographic gradient is from north to south; altitudes in the study unit range from 1,550 feet above sea level near the headwaters of the Mad River to 450 feet along the Ohio River at Cincinnati. Average annual precipitation in the study unit ranges from 35 to 43 inches and increases towards the south; about one-third of the precipitation becomes surface runoff. Average annual air temperature ranges from 51° Fahrenheit in the north to 54° in the south. Average snowfall in the study unit is 20 to 30 inches per year.
White River Basin
Seven physiographic units are contained in the White River Basin. Differences between these physiographic units are caused by bedrock geology and extent of glaciation. The Tipton Till Plain, defined by glacial features, is a flat to rolling glacial till plain that covers the northern half of the basin. The Wabash Lowland is in the southernwestern part of the Basin and is an area of broad, flat valleys and gently rolling plains. The remaining five physiographic units are controlled principally by bedrock. The Crawford Upland and the Norman Upland are westward-sloping, unglaciated upland areas with narrow ridge tops and steep slopes. The Mitchell Plain lies between the two upland units and is a karst plain with with numerous sinkholes and solution features. The Scottsburg Lowland is east of the Norman Uplandand and is an area of low relief and extremely broad, flat valleys. The Muscatatuck Regional Slope, in the southeastern part of the Basin, is a westward-sloping plain characterized by moderate relief and by bedrock outcrops in the stream channels. The White River Basin has a humid continental climate. Average annual precipitation ranges from 38 inches in the north to 44 inches in the south central part of the basin. Average annual air temperatures ranges from 51° Fahrenheit in the north to 55° Fahrenheit in the south.
Ground Water
Great and Little Miami River Basins
The principal aquifer in the study unit is a complex, buried-valley system that underlies the Great and Little Miami River valleys. This aquifer has been designated a sole-source aquifer by the U.S. Environmental Protection Agency and is the principal source of drinking water for 1.6 million people. The aquifer is found in bedrock valleys incised into uplifted Silurian and Ordovician bedrock by a tributary of the Teays preglacial drainage system. These valleys were buried by sediments deposited by advancing glaciers (tills) or filled in by coarse-grained sediments deposited by glacial meltwaters (outwash). Depth to water in most parts of the aquifer is less than 20 ft; supply wells completed in the sand and gravel deposits commonly yield more than 1,000 gallons per minute. At several locations, high pumping rates are maintained by induced infiltration of river water or by artificial recharge lagoons. In the northern part of the study unit, Silurian limestones and dolomites form a carbonate bedrock aquifer that is used for domestic and small industrial supply. Wells completed in the carbonate aquifer typically yield between 10 and 100 gallons per minute. In the southern part of the study unit, the shale-rich Ordovician bedrock is poorly permeable and is used for domestic-water supply only where other sources of water are not available.
White River Basin
There are two primary aquifers in the basin, unconsolidated aquifers and bedrock aquifers. The unconsolidated aquifers are either glaciofluvial or till. Glaciofluvial aquifers are narrow bands of homogenous sand and gravel deposits along and beneath streams throughout the White River Basin. Widths of the glaciofluvial aquifers range from 0.1 mi on small streams to 6 miles wide on the larger White and East Fork Rivers. Typically, the thickness of the glaciofluvial ranges from 20-80 feet but are greater than 100 feet in several places. The depth to water is generally 10-25 feet. Well yields in the thick glaciofluvial deposits can be up to 2,000 gal/mi. The till aquifers are located north of the Wisconsin glacial boundary and consist of sand and gravel deposits enclosed in thicker sequences of silty-clay and clay till. The thickness of these mostly confined sand and gravel deposits range from 5-50 feet but are typically 5-10 feet. In the northern part of the basin, Silurian and Devonian carbonate aquifers underlie the Tipton Till Plain and Scottsburg Lowland physiographic units. These aquifers are almost always confined and consist of fractured carbonates of Silurian and Devonian age. Depth of wells completed in Silurian and Devonian carbonate aquifers are generally 50-250 feet. Well yields range from 20-600 gal/min. In the south-central part of the basin, the Mississippian carbonate aquifer is or near the land surface throughout the Mitchell Plain physiographic unit. Ground water and surface water are connected and many streams periodically disappear into surface openings, flow underground for a distance, and reappear at a downgradient surface opening. Aquifer recharge is primarily from precipitation. Average well yield is 5 gal/min but may be as high as 30 gal/min.
Water Supply
Great and Little Miami River Basins
In 1995, an estimated 745 million gallons per day was withdrawn from streams and aquifers in the Great and Little Miami River Basins. Of this, approximately 48 percent was withdrawn from surface-water bodies whereas the remaining 52 percent was derived from ground-water sources. Excluding withdrawals from the Ohio River, almost 92 percent of the water used for public, domestic, commercial, and industrial supply was derived from ground-water sources. Most of this ground water is pumped from the buried-valley aquifer underlying stream valleys associated with the Great and Little Miami Rivers.
Although rivers in the Great and Little Miami River Basins greatly influenced the early development of the region's economy, it has been the availability of abundant ground-water supplies that has spurred rapid growth and development in the region since the beginning of this century. Another important factor affecting growth and development is the relatively unspoiled nature of the streams and rivers. The Little Miami River (a State and National Scenic River), the upper Great Miami River and its tributaries, and the Whitewater River in Indiana largely contain high-quality warmwater habitats with biologically diverse fish and wildlife populations.
White River Basin
In 1995, an estimated 1,284 million gallons per day was withdrawn from streams and aquifers in the White River Basin. Of this, approximately 84.5 percent was withdrawn from surface-water bodies whereas the remaining 15.5 percent was derived from ground-water sources. The major water use in the White River Basin was cooling water for fossil-fuel thermoelectric power generation plants (about 63 percent of total water use). Virtually all water withdrawn for cooling at power generation plants is returned to the stream and none of the power generation plant intakes are located on the East Fork White River. Public water supply accounted for about 21 percent of the total water use. Of the water withdrawn for public supply, about 59 percent was surface water and 41 percent ground water.