Brief description of the White River Basin

The White River Basin can be divided into six hydrogeomorphic regions that have similar natural characteristics on the basis of geologic, geomorphologic, and hydrologic factors. Three of the regions---the till plain, glacial lowland, and fluvial deposits are defined primarily by glacial deposits. The remaining three---the bedrock upland, bedrock lowland and plain, and karst plain---are defined primarily by bedrock geology. The till plain, glacial lowland, and fluvial deposits are the most intensively farmed regions in the White River Basin. The till plain, an area of low topographic relief in the northern part of the basin, typically is covered by 100 to 200 feet of silty-clay till interspersed with thin (5 to 10 feet) layers of sand and gravel. The relatively impervious till limits infiltration and promotes surface runoff. Tile drains are common in the till plain. The glacial lowland, in the southwestern part of the basin, typically is covered by 0 to 100 feet of loess (wind-blown silt), silty-clay till, dune sands, and lake clays overlying coal-bearing shales and sandstones. In general, soils in the glacial lowland are more permeable and better drained than soils in the till plain. However, drainage is poor in parts of the glacial lowland where clay-rich deposits are prevalent and in low-lying areas where the water table tends to be shallow. Where such conditions exists, drainage ditches and tile drains are common. The physiography of the rest of the basin is controlled by bedrock features, although the southeastern part of the basin (the bedrock lowland and plain) is covered by a thin layer of glacial till. Soils in this region are generally highly erosive or poorly drained; subsurface drainage is difficult because tile drains tend to fill with silt. The bedrock uplands are unglaciated and are characterized by a hill and valley landscape with higher relief than other parts of the basin. Bedrock outcrops are common in this region and soils are generally thin. The karst plain is characterized by numerous sinkholes and solution features.

Hydrogeomorphic regions of the White River Basin

The population of the White River Basin in 1990 was approximately 2.1 million people, about three-fourths of which are concentrated in the northern part of the basin. The Indianapolis Metropolitan Area accounts for about 60 percent of the total population. About 85 percent of water used in the basin is from surface-water sources; 45 percent of drinking water is from surface-water sources. The primary land use is agriculture which accounts for about 70 percent of the basin. Extensive soybean and corn production occurs in the northern, southwestern, and southeastern parts of the basin. In 1992, about 22 percent of the basin was planted in corn, and about 18 percent was planted in soybeans. These two crops accounted for 78 percent of all cropland. Other crops account for a much smaller percentage of the basin and include hay (about 3 percent) and wheat (about 2 percent) and, to a much lesser extent apples, barley, cucumbers, green beans, melons, oats, potatoes, pumpkins, rye, sorghum, strawberries, tobacco, and tomatoes (each less than 0.1 percent). The south-central part of the basin is not farmed as extensively as other parts because of the hill and valley landscape. Most of the forested land in the basin is located in this region. There is significant industrial development in the cities of Indianapolis, Muncie, and Anderson.

Land use in the White River Basin

Herbicides applied to corn and soybeans dominate pesticide use in the White River Basin. Herbicides are applied in the spring during planting to virtually all of the corn and soybean crop. Insecticides are applied during the summer to about 25 percent of the corn crop and typically are not applied to soybeans. Triazine (primarily atrazine and cyanazine) and acetanilide (acetochlor, alachlor, and metolachlor) compounds are the most commonly used herbicides. Herbicide use on corn accounts for about 70 percent of the total agricultural use of pesticides in the basin. About 96 percent of the total agricultural pesticide use is herbicide and insecticide use on corn and soybeans. Fungicide and insecticide use on apples, tomatoes, and watermelons (2.2 percent of use) and herbicide use on wheat, pasture, and hay (1.0 percent of use) accounts for most of the remaining agricultural pesticide use.

Estimated use of the 16 most common agricultural pesticides in the White River Basin
(1992-94 average annual usage, except acetochlor, which is 1994 usage.)

Use of alachlor on corn and soybeans decreased by about 70 percent between 1991 and 1995 in Indiana. Use of butylate, the fourth most commonly used herbicide in 1991, has essentially ceased. Use of acetochlor, metolachlor, and cyanazine increased during the same time period. Acetochlor, a corn herbicide registered for use in 1994, was the third most used compound in Indiana in 1995. Because of increased use of no-till farming practices in the State, there has been a significant corresponding increase in the use of glyphosate and 2,4-D. These herbicides are used prior to planting to kill all plant growth.

Nonagricultural use of pesticides in the White River Basin is not as well documented as agricultural use. Insecticides typically account for a larger percentage of the total amount of pesticides used in urban areas than in agricultural areas. The insecticides allethrin, chlorpyrifos, diazinon, lindane, malathion, and propoxur, and the herbicides 2,4-D, MCPP, and glyphosate commonly are used in urban areas.

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Last Update: 05/29/2001
This page is maintained by Charles Crawford (send questions or comments to cgcrawfo@usgs.gov).
The URL for this page is http://in.water.usgs.gov/nawqa/wr00002.htm
U.S. Geological Survey, 5957 Lakeside Boulevard, Indianapolis, IN 46278, USA