Ohio State University Extension

Food, Agricultural and Biological Engineering

590 Woody Hayes Dr., Columbus, Ohio 43210

Knox County Water Resources

AEX-480.42

F. John Barker III
Kristina M. Boone
Larry C. Brown

Water is a resource often taken for granted. In recent years, water availability and quality have become important public concerns in Knox County. The county's population of 47,473 (1990 census data) is predominantly rural, and about 55 percent of all households rely on private wells for their water supply. By understanding where water is obtained and how it is used in the county, residents can gain a better appreciation for their water. Providing a brief overview of Knox County's water resources, this fact sheet is intended to help increase public awareness and understanding of water resources. Water resources terminology used in this publication is included in Surface and Ground Water Terminology, Fact Sheet AEX 460, which provides a listing of generally accepted water resource definitions. Ohio State University Extension publications are available through all Ohio county Extension offices.

Precipitation

An average of almost 40 inches of precipitation falls on Knox County annually. Although variations in precipitation may occur from place to place within the county, the long-term averages across the county are relatively close. A 30-year period of record at four different precipitation recording sites demonstrates this variation. The sites and the average annual precipitation recorded there are: Centerburg, 40 inches; Danville, 40 inches; Fredericktown, 40 inches; and Greer, 38 inches. Figure 1 illustrates the average monthly precipitation for the county for the period 1961 to 1990. Based on this 30-year record averaged for all four sites, the average precipitation is 3.3 inches per month, with January and February (2.2 inches) typically being the driest months, and July (4.3 inches) the wettest. There can be, however, extreme variations in some years and in certain months within a year. Such seasonal and yearly extremes, which may have serious consequences, often are not apparent from the long-term precipitation information.

Figure 1. Average monthly precipitation (in inches) in Knox County, Ohio (1961-1990);

Surface-Water Resources

The major drainage basin in Knox county is the Kokosing River. Major feeder streams that drain into this river include: Jelloway Creek, Little Jelloway Creek, Schenck Creek, Big Run, Dry Creek, North Branch and East Branch. A small area in northeast Knox County drains into tributaries of the Mohican River. Both of these drainage basins are part of the Muskingum River basin, which flows into the Ohio River, a major source of water for southeastern and southern Ohio, and other states. A generalized surface-water map of Knox County is given in Figure 2.

Surface waters are affected by the soil type and topography of the land adjacent to them, and the way humans use the land. Land use, such as residential development, construction, and agricultural production, can increase the amount of sediment entering a body of water. The type of soils in an area also influences surface water because of the soil's infiltration capacity. With some soils, rainfall is more likely to run off, while other soils allow water to infiltrate more readily.

The Kokosing River basin covers 482 square miles. This area represents a vast majority of Knox County as well as smaller portions of five other surrounding counties. The northeastern portion of the county is drained by the Mohican River basin. This basin drains approximately 999 square miles but only a small portion of this total is contributed by Knox County.

The county contains approximately 340,380 land acres. Agriculture accounts for approximately 86 percent of all Knox County land use. Forty-five different soil types are present within the county, the majority of which are well-drained to somewhat poorly-drained soils. Among the 1,375 total acres of lakes in the county, Knox Lake (474 acres), Apple Valley Lake (485 acres), and the North Branch of the Kokosing Lake (154 acres) comprise a significant portion of this acreage. About 410 linear miles of major streams and rivers course through the county as well (estimated from ODNR Div. of Water river basin maps). This availability lends itself to many uses by both communities and individuals.

Figure 2. Surface-water resources in Know County, Ohio (adapted from ODNR Division of Water river basin maps; illustration prepared by R. A. Roberts).

Ground-Water Resources

Three principal aquifers underlie Knox County, including an unconsolidated coarse-grain aquifer, unconsolidated fine-grained aquifer, and sedimentary sandstone aquifer. These aquifers provide adequate water supplies for both individual wells and several villages. Unconsolidated coarse-grain aquifers, located in the western one-third of Knox County, consist of highly permeable sand and gravel deposited by glaciers into preexisting river valleys. These highly productive aquifers can produce well yields as high as 1,000 gallons per minute (gpm) at depths of 55 to 155 feet. A fine-grained unconsolidated aquifer, located in the southwestern corner and in other portions of the county, is similar to the unconsolidated coarse-grained aquifer but is less permeable because it consists of a higher proportion of mixed fine sands, silt and clay. Typical yields from this aquifer will fall in the range of 25 to 50 gpm. Average well depths found in this aquifer fall within a range of 66 to 165 feet. Knox County's primary ground-water source is a sandstone aquifer. This aquifer is characterized as massive to thin-bedded units of fine-grained sandstone, with yields usually ranging from 5 to 25 gpm. This aquifer may be confined or unconfined, and well depths can range from 40 to 225 feet. An overview of the ground-water resources in the county is given in Knox County Ground-Water Resources, AEX-490.42.

The yield of a well will vary considerably depending on the age and depth of the well, well construction, the diameter of the casing, pump capacity and age, and more importantly, properties of the geologic formation. Specific information on ground-water availability and wells can be obtained by contacting the Ohio Department of Natural Resources (ODNR), Div. of Water.

Where Does the Water Go?

Based on long-term weather records, Ohio receives an average of 38 inches of precipitation per year. These 38 inches move through a complex path called the hydrologic cycle. Of these 38 inches, about 10 inches (26 percent) become runoff, which moves immediately to surface-water bodies like streams and lakes. Two inches are retained at the ground surface and evaporate back into the atmosphere in a relatively short period of time. Twenty-six of the 38 total inches enter the soil surface through infiltration. Twenty of these 26 inches go into soil storage and later are returned to the atmosphere by the combination of evaporation and transpiration (evapotranspiration). The remaining 6 inches of precipitation (16 percent of the total) have the potential to recharge the ground-water supply. Two of these 6 inches eventually move to springs, lakes, or streams as ground-water discharge. The remaining 4 inches either return to the atmosphere by evapotranspiration or are withdrawn to supply water needs. For further reading, refer to Ohio's Hydrologic Cycle, AEX 461.

Statewide averages applied to the county's average annual precipitation provide a rough estimate of how many inches will result in runoff and how many inches have the potential to reach aquifers. Based on statewide averages of runoff and ground-water recharge, Knox County's 40 inches of average annual precipitation result in about 10 inches of runoff to streams and lakes, and about 6 inches have the potential to recharge aquifers, annually. Values for particular locations will differ according to local conditions.

Water Use

Ground water is the water source for all households in Knox County. Approximately one-half of the county households obtain their water from private wells, while the remainder are served by public water systems. Private well use continues to increase as population growth occurs in areas not served by public water supplies. Water use for each of Knox County's public water-supply systems is given in Table 1. For each water system, this table presents an estimate of the population served, water source, estimated daily usage and treatment plant capacity.

The county's largest public-water system is the city of Mount Vernon, which uses ground water for its supply. The Mount Vernon system also supplies the village of Gambier. The other public-water systems in the county are the villages of: Centerburg, Danville, Fredericktown, Howard and Martinsburg. Like Mount Vernon, these systems also use ground water for their supply. There are 10 additional smaller, community water supplies in the county.

Some water users in Ohio must register their withdrawals with the ODNR Div. of Water. Through the Water Withdrawal Facility Registration Program, owners of facilities that could withdraw 100,000 gpd (70 gpm) or more must register those facilities. Information collected through this program includes withdrawal capacity, ground- or surface-water sources, location and type of water use, and location of discharge points. The program is for registration only, and not for allocation or permission. Registered withdrawers file annual reports of their water use. This information helps planners at ODNR determine the availability of water for projected needs and better manage and protect Ohio's water resources. Documenting water use also provides official records for individual uses. For more information, contact ODNR, Div. of Water.

Knox County also has 14 non-transient non-community water supplies, including four schools and 10 businesses. Non-transient non-community systems are small public water supplies that serve more than 25 of the same people for six months of the year.

Table 1. Water Use in Knox County, Ohio.1
Public Water System	Population Served	Primary Water Source	Water Usage (GPD)2	Treatment Plant Capacity (GPD)
Centerburg	1,360	Ground Water	140,000	288,000
Danville	1,000	Ground Water	130,000	273,600
Fredericktown	2,450	Ground Water	230,000	432,000
Gambier3	2,100	Ground Water	250,000	0
Knox Sewer & Water Dist. 1 (Howard)	2,500	Ground Water	362,000	NA4
Martinsburg	240	Ground Water	8,500	144,000
Mount Vernon	14,550	Ground Water	2,870,000	5,000,000
Other5	1,812	Ground Water	117,950	0
1 Estimates from Ohio EPA using 1993 data, adjusted by Leonard Black, ODNR Div. of Water.
2 GPD = gallons per day.
3 Water supplied by Mount Vernon.
4 NA = information not available.
5 Other includes mobile home parks and investors.

Water Quality

Natural processes and human activities affect the quality of our water supplies. Throughout Ohio, human activities contribute to nonpoint source pollution, through which a major portion of the sediment, nutrients, acids and salts, heavy metals, toxic chemicals, and pathogens enter the state's water resources. Nonpoint source pollution is the introduction of impurities into a surface-water body or an aquifer, usually through a non-direct route and from sources that are "diffuse" in nature. This type of pollution affects both ground and surface water. Examples include automobile emissions, runoff from parking lots, runoff and drainage from agricultural fields, feedlots, and home gardens, and runoff and drainage from construction, mining and logging.

Ground Water

As water moves through the deposits underlying Knox County, it dissolves and carries in solution minerals contained in these deposits. The unconsolidated aquifers in the western part of the county may contain excessive concentrations of calcium carbonate, which causes hard water. Iron and hydrogen sulfide (rotten egg smell) also are common in certain areas. AEX-490.42 summarizes some of the county's natural ground-water quality aspects.

Human activities, such as agricultural production, domestic waste disposal, and lawn and turf care, may have some influence on the county's ground-water quality. In a 1989 study by Heidelberg College, 738 wells in Knox County (the highest in Ohio) were sampled for nitrate content, of which 416 (56 percent of total) contained nitrate-nitrogen concentrations in the range of 0 to 0.3 parts-per-million (ppm). This range is assumed to represent natural background levels. Values of 0.3 to 3.0 ppm may or may not indicate human influence; 195 wells (26 percent) tested in this range. The 115 wells (16 percent) that tested in the range of 3.0 to 10 ppm may indicate elevated concentrations resulting from human activities. Only 12 wells (1.6 percent) tested at over 10 ppm nitrate-nitrogen, which exceeds the safe drinking-water standard. The average test value for the 738 wells tested was 1.46 ppm. Design, location, and condition of a well, as well as the characteristics of the soils and geologic formations in which the well is constructed, influence the potential for pollutants to enter the well.

Bacterial counts are another indicator of ground-water quality. The Knox County Health Department tests water samples for concerned citizens. Results of these tests indicate that to date no bacterial problems have been found in Knox County.

Surface Water Runoff and sediment from residential development, construction sites, and agricultural lands, may enter the county's streams and lakes. Also, runoff may carry other pollutants, such as lawn and agricultural chemicals (pesticides and fertilizers), effluent from septic systems, oil and gas from spills, and industrial wastes. Many acres of Knox County agricultural land need one or more different types of conservation treatment to either protect or improve the soil and water resources. The USDA-Soil Conservation Service (USDA-SCS) estimates that over 779,000 tons of topsoil erode on Knox County agricultural land annually. More than 54,000 acres, or 16 percent of county acreage, are eroding at rates greater than five tons per acre. To address this situation, Knox County farmers have been on the leading edge in adopting conservation tillage practices, such as no-till crop production. In 1990, 52,200 Knox County acres were farmed with no-till cropping practices.

Through the Ohio Nonpoint Source Assessment and Water Resources Inventory, Ohio Environmental Protection Agency (Ohio EPA) and ODNR have found that 13,000 stream miles in Ohio have been affected by nonpoint source pollution. Knox County contains portions of several streams and their tributaries that have been classified by the Assessment as being affected by nonpoint source pollution. Based on the findings of the Assessment and Inventory, the Ohio Nonpoint Source Management Plan has been implemented to help improve the quality of the state's waters. For specific information on results of the Assessment and details of the Management Plan for the county, contact the Ohio EPA Central District Office (2305 Westbrooke Dr., Col., OH 43266-2198).

Overall, Knox County has a safe supply of water, and maintaining the quality of this water is essential. County citizens have a major challenge to protect water resources from pollutants that could affect the quality of the water supply. For more information about nonpoint source pollution, refer to Nonpoint Source Pollution: Water Primer, AEX 465, available from your county Extension office.

Summary

Water availability and quality are important public concerns. Water problems can be both costly and inconvenient. While the present and future availability of water is good for Knox County, water is a precious resource that must be conserved and protected. We must all work together to maintain an adequate supply of good quality water.

This fact sheet provided information on water facts for Knox County. For more information on water resources and drinking-water quality in the county, contact the Knox County office of Ohio State University Extension. In addition, the following agencies may be able to provide information on other water resources topics in the county: Knox Soil and Water Conservation District; Knox County Health Department; ODNR Div. of Water (Fountain Square, Col., OH 43224); U.S. Geological Survey (USGS), Ohio District (975 W. Third Ave., Col., OH 43212); Ohio EPA (1800 WaterMark Dr., Col., OH 43266); and Ohio Department of Health (PO Box 118, Col., OH 43226).

Bibliography

Doane's Agricultural Report. 1992. Farm Water Systems.

Estimated Water Use in Ohio, 1990, Public Supply Data. 1993. USGS. Open-File Report 93-72.

Floods at Mount Vernon (Knox County), Ohio. 1961. USGS Hydrologic Investigations Atlas 40.

Gazetteer of Ohio Streams. 1960. Ohio Water Inventory Report No. 12. ODNR Div. of Water.

Ground-Water Resources of Knox County. 1980. J.J. Schmidt. ODNR Div. of Water. (map).

Hydrologic Atlas for Ohio: Average Annual Precipitation, Temperature, Streamflow, and Water Loss for the 50-Year Period 1931-1980. 1991. L.J. Hartstine. Water Inventory Report No. 28. ODNR Div. of Water.

Inventory of Municipal Water-Supply Systems by County, Ohio. 1977. Ohio Water Inventory Report No. 24. ODNR Div. of Water.

Inventory of Ohio's Lakes. 1980. Ohio Water Inventory Report No. 26. ODNR Div. of Water.

Knox County Ground-Water Resources. 1993. F.J. Barker III, A.W. Jones, L.C. Brown and K.M. Boone. AEX-490.42. Ohio State University Extension.

Knox County, Ohio Soil Survey, 1980. USDA-SCS.

Monthly Station Normals of Temperature, Precipitation, and Heating and Cooling Degree Days, 1961-90, Ohio. 1992. Climatology of the United States, No. 81 (by state). NOAA.

Nitrate and Pesticides in Private Wells of Ohio: A State Atlas. 1989. Water Quality Laboratory, Heidelberg College.

Nitrate In Drinking Water. 1987. K.M. Mancl. Bulletin No. 744. Ohio State University Extension.

Nonpoint Source Pollution: Water Primer. 1993. R. Leeds and L.C. Brown. AEX 465. Ohio State University Extension.

Ohio Ground-Water Quality. USGS National Water Summary - Ohio. 1986. USGS. Water-Supply Paper 2325.

Ohio Ground-Water Resources. USGS National Water Summary - Ohio. 1984. USGS. Water-Supply Paper 2275.

Ohio Nonpoint Source Management Program. 1993. ODNR. Fountain Square, Col., OH 43224-1387.

Ohio Surface-Water Resources. USGS National Water Summary - Ohio. 1985. USGS. Water-Supply Paper 2300.

Ohio Water Resource Inventory: Executive Summary and Volumes 1-4. 1992. Ohio EPA. Col., OH 43266-0149.

Ohio's Hydrologic Cycle. 1990. L.C. Brown and K.M. Coltman. AEX 461. Ohio State University Extension.

Private Water Systems Handbook. 1987. MWPS-14. Midwest Plan Service, Ames, IA.

Soil and Water Conservation District Resource Inventory. 1985. USDA-SCS.

Southeast Ohio Water Plan. 1978. ODNR Div. of Water.

State of Ohio Nonpoint Source Assessment: Volumes 1-6. 1990. Ohio EPA. Col., OH 43266-0149.

Surface and Ground Water Terminology. 1990. L.C. Brown and L.P. Black. AEX 460. Ohio State University Extension.

Water - Ohio's Remarkable Resource. 1982. ODNR Div. of Water.

Withdrawal and Distribution of Water By Public Water Supplies in Ohio, 1985. USGS. Open-File Report 89-423.

Acknowledgments

This publication was produced through the Ohio Water Resources Education Project, in cooperation with: ODNR Div. of Water; Ohio EPA; USGS, Ohio District; and Ohio Department of Health (ODH). Project leaders are Larry C. Brown and Kristina M. Boone. Support was provided, in part by: the cooperating agencies; Knox County office of OSU Extension; Knox County Commissioners; Knox Soil and Water Conservation District (SWCD); Overholt Drainage Education and Research Program; and USDA Extension Service Grant No. 90-EWQI-1-9018.

The project leaders express appreciation to the following reviewers: Mark Smith (USDA-SCS); Rob Clendening (Knox SWCD); Jim Fridrich (Knox County Health Department); James M. Raab, David Cashell and Leonard Black (ODNR Div. of Water); Scott Golden (Environmental Health, ODH); Ron Veley and Steve Hindall (USGS, Ohio District); James Wade (USDA-SCS); Linnea Saukko and Carolyn Diller (Ohio EPA, Central District); Jay Fleming (Ohio EPA Div. of Drinking and Ground Water); and Larry Antosch (Ohio EPA Div. of Surface Water).

A special thanks to Michelle Roby and Ross A. Roberts (Agricultural Engineering Undergraduate Assistants) for help in manuscript and graphics preparation, and Judy Kauffeld, Publications Editor (Section of Communications and Technology, Ohio State University), for editorial and graphic production.