Figure 1. Ground-water resources of Fulton County, Ohio (adapted from Ground-Water Resources of Fulton County map, A.J. Walker (1991), ODNR Division of Water, illustration prepared by Carlos Lopez).
Water stored under the earth's surface is a plentiful, yet precious, resource in most areas of Ohio. Many human activities may affect the quality and quantity of this resource. However, the availability and quality of this resource are influenced directly by the properties of the geologic formations that hold water. The chemical and physical nature of these formations varies from area to area, creating a wide range of water yields and quality at different depths and formations. This publication contains information about the ground-water resources underlying Fulton County. Its purpose is to help the reader better understand the factors that influence the quantity and quality of ground water. An overview of the county's water resources is provided in the publication Water Resources of Fulton County, AEX-480.26.
Much of the water-resource and water-quality terminology used in this publication is described in Extension Fact Sheets AEX 460 and 465. Ohio Extension publications are available through the Fulton County office of Ohio State University Extension.
Geologic formations (e.g., sand, gravel, limestone, sandstone) have the ability to receive, store, and transmit water. In general, if a formation is capable of yielding enough water to support a well or spring, it is called an aquifer. The material from which the formation was originally made influences its ability to store and transmit water. For example, sand and gravel allow water to flow through easily. By comparison, shale, which originated from compacted layers of mud and clay, generally allows very little water to flow through it unless the shale is highly fractured.
Shale underlies virtually all of Fulton County. The shale base is overlain by a varying thickness of glacial till, which contains an unsorted mixture of clay, silt, sand, gravel, and boulders. These materials were deposited as a result of glacial processes that occurred approximately 10,000 to 20,000 years ago. Sand and gravel deposits within the till are the predominate aquifer type in the county. The ability of these aquifers to supply water varies greatly from east to west because of the composition of glacial deposits. Northwestern Fulton County, which includes the area north of Archbold and Tedrow to just east of Lyons is made up of thick deposits of coarse sand and gravel. These aquifer deposits, recharged from the land area to the northwest of the county extending into Michigan, can provide plentiful water supplies.
A large part of the remaining portion of Fulton County is made up of finer glacial deposits, with more clay and silt, and less gravel compared to the coarser deposits described above. Ground water in the eastern part of the county occurs in lenses (or pockets) of sand and gravel deposited by glacial processes. Ground water in this area is less plentiful, and the ability to find the quantity and quality of water suitable for domestic supplies is more difficult.
The extreme eastern portion of Swan Creek Township in eastern Fulton County is the only area of limestone bedrock aquifers. Limestone aquifers usually are adequate sources of ground water because of naturally occurring fractures and joints which store water and provide channels for water flow.
The yield of a well, in gallons per minute (gpm), will vary considerably depending on the age and depth of the well, the diameter of the casing, well construction, pump capacity and age, and most importantly, properties of the geologic formation. The exact yield and depth of each well will depend on the properties of the geologic formation at the specific location of the well.
To support the development of ground-water availability assessments in Ohio, the Ohio Department of Natural Resources (ODNR), Division of Water, maintains a statewide database of more than 700,000 well logs. The Water Resources Section of the Division manages this valuable database, which includes some information collected by the U.S. Geological Survey (USGS) and the Ohio Environmental Protection Agency (Ohio EPA). Since 1948, well-log information has been collected to increase the understanding of the ground-water resources in Ohio (since the early 1950's, well drillers have been required by State law to file a construction log of each new well). Geologists and hydrogeologists continue to study the state's ground-water resources. As a result, Ohio is one of only a few states that has been completely mapped for ground-water availability (each county has a published, county-specific, ground-water map).
Estimates of the size, shape, geologic make-up, and yields of aquifers have been mapped for Fulton County. The map presented in Figure 1 is a generalized representation of the water-bearing formations underlying Fulton County (adapted from map by A. C. Walker, 1991). This illustration is based on a hydrogeologic interpretation of the well-log data from Fulton County and surrounding areas. It should be used only as a guide to understanding the ground-water resources in the county. The section below provides a brief description of the types of aquifers illustrated on the map in Figure 1.
Figure 1. Ground-water resources
of Fulton County, Ohio (adapted from Ground-Water Resources of Fulton
County map, A.J. Walker (1991), ODNR Division of Water, illustration
prepared by Carlos Lopez).
Area A in Figure 1 denotes areas of thick glacial deposits of sand and gravel, fine sand, and layers of clay. Properly developed wells may supply 100 to greater than 500 gpm. The total thickness of the glacial deposits is 135 to 150 feet.
Figure 2 is a generalized cross section (referenced in Figure 1 as the line X-X'), which shows the range of depth to bedrock as well as the variation in composition of the glacial till within Fulton County.
Figure 2. Generalized cross
section of Fulton County, Ohio (adapted from Underground Water Resources
map, A-8, ODNR Division of Water; illustration prepared by Kim
Wintringham).
The composition and yields of the formation illustrated as Area B is similar to that of Area A. However, artesian wells and free flowing springs are common in this three to five mile wide area extending through Gorham and Franklin Townships. As a result of the difference in elevation of the water level and ground surface between two points (in this case the upland recharge area and Area B), the confining pressure from the overlying clay causes some wells to flow freely once developed.
Area C illustrates where large ground-water supplies may be available in the carbonate bedrock aquifer at depths of greater than 100 feet. Potential yields are 100 to 500 gpm. Farm and domestic supplies can usually be obtained at shallower depths (50 to 100 feet). Water quality is a concern in wells where hardness and hydrogen sulfide are found in objectionable amounts.
High yielding wells can be developed in the carbonate aquifer which lies beneath the shale bedrock in Area D. Yields from this aquifer are similar to those obtained from Area C. However, hydrogen sulfide and dissolved solids can be expected.
Glacial deposits in Area E are made up of fine sand and silty clay which contain localized lenses of sand and gravel. Yields of up to 10 gpm may be obtained. Deposits range in thickness from 45 feet in the eastern portion of the area to over 200 feet to the west. Dry holes, methane, and hydrogen sulfide are sometimes encountered.
The eastern part of Fulton County generally has a shallow water-table level. Some residents have developed dug wells of 15 or less feet in depth. These wells have a low yield potential because of the characteristics of the surrounding sand, silt, and clay that restrict recharge. Dug wells also have a water quality caution because of the great potential for contamination from nearby activities.
Small domestic supplies may be obtained from the shale bedrock underlying Area F. Expected yields are less than 10 gpm, and dry wells have been noted in this area. Water quality also is a concern. Methane and hydrogen sulfide are often encountered.
The water level in any well does not remain constant, but changes in response to several factors. Rainfall distribution and amount may affect the ground-water recharge and discharge, and subsequently may affect the water level in area wells. Also, wells that are hydraulically connected to a stream may show fluctuations in the water level as the stream level changes. In some cases, depending upon the hydraulic properties of the geologic formation, the intense pumping of a well or number of wells for irrigation or industry, may cause the water level in some nearby wells to be lowered.
The ODNR Division of Water, in cooperation with the USGS, manages a statewide network of water-level observation wells. The network currently consists of 102 State-operated sites equipped with continuous water-level recorders. Water-level data are collected to provide a database for scientists and water resources managers to learn about short- and long-term water-level fluctuations in various aquifers.
While the ODNR Division of Water does not monitor ground-water levels in any well in Fulton County, it does monitor wells in neighboring Henry, Lucas, and Williams counties. These wells provide some indication of how ground-water levels may change in similar aquifer materials in Fulton County. Observation Well HY-2, located in Henry County (southwest of McClure), has been continuously monitored since June 1971. Observation Well LU-1, located in Lucas County (at Toledo State Hospital), has been continuously monitored from March 1946 to September 1982, and again from January 1985 to the present, with periodic measurements from October 1983 to January 1985. Well HY-2 is 300 feet deep, and has a land surface elevation of 680 feet above sea level. Well LU-1 is 523 feet deep and has a land surface elevation of 624 feet above sea level. Both wells are drilled into a limestone aquifer. An observation well, constructed in sand and gravel, is located in Williams County (Observation Well WM-3, in Bryan). Continuous records have been maintained since October 1984. Well WM-3 is 174 feet deep and has a land surface elevation of 760 feet above sea level.
Continuous daily ground-water level measurements at Observation Well HY-2 show a record low water-level measurement of 26.4 feet below the land surface in December 1994; and a high water-level measurement of 14.6 feet in March 1978. At Observation Well LU-1, a record low water-level measurement of 117.2 feet below land surface was recorded in September 1957; and a high water-level measurement of 56.9 feet recorded in April 1987. Records for the sand and gravel well (WM-3) indicate a record low water-level measurement of 27.4 feet below land surface in June and July 1988, and a high water-level measurement of 15.2 feet recorded in January 1987.
Various state and federal agencies have participated in programs to determine the ground-water quality in Ohio. For five wells in Fulton County, water-quality data were available from the ODNR Division of Water. In Figure 1, these wells are noted as Chemical Analysis Sites 1 through 5. These sites are municipal and private wells.
The results from some of the chemical tests performed on these Fulton County wells are given in Table 1. The chemical constituents listed are total dissolved solids, calcium, magnesium, iron, manganese, chloride, sulfate, and fluoride. For comparison purposes, secondary drinking water-quality standards for these chemical constituents also are shown. These standards are established by the U.S. Environmental Protection Agency (USEPA) for public water systems for aesthetic reasons (taste, odor, appearance, etc.), and are not enforceable. These chemical constituents do not pose a risk to human health (see notes in Table 1). For private wells, there are no legally enforceable drinking water-quality standards other than total coliform, which is an indicator of bacteriological quality.
Ground water, whether obtained from bedrock or glacial deposits, may require some treatment. In some areas, water containing calcium carbonate (CaCO3, i.e. hard water), and iron concentrations greater than 0.3 ppm may require treatment for some uses (see notes in Table 1). Wells drilled into shale or limestone may produce water that contains objectionable quantities of hydrogen sulfide gas (rotten egg odor). Hydrogen sulfide concentrations as small as 1 ppm can result in an offensive, rotten egg odor and taste. In general, the probability of obtaining hydrogen sulfide in objectionable amounts increases with the depth drilled.
The information in Table 1 can be used as a guide to what one might expect from an existing or new well developed in similar geologic material in the county. This information provides a general representation of the quality of water at the time of sampling. The data provided in Table 1 were taken from a water sample obtained just after the well was put into operation. These five wells were developed in sand and gravel formations underlying Fulton County, and range from 45 to 165 feet deep with yields of 5 to 300 gpm. There was some variation in the concentrations of the chemical constituents in these samples. Just as well yields differ, water quality will vary depending on aquifer properties at the specific location of each well. One should not forget that many human activities also affect the quality of ground water (see AEX 465).
| Table 1. Chemical constituents of selected Fulton County, Ohio, wells.1 | ||||||
|---|---|---|---|---|---|---|
| Well No. | 1 | 2 | 3 | 4 | 5 | WQ Std2 |
| Well Depth (feet) | 96 | 45 | 102 | 50 | 165 | |
| Capacity (gpm) | na3 | 300 | na | na | 5 | |
| Depth to Bedrock (feet) ne4 | ne | ne | ne | 140 | ||
| Water-Bearing Formation5 | SG | SG | SG | G | SG | |
| Chemical Constituents6 | ||||||
| Total Dissolved Solids | 502 | 475 | 1312 | 898 | 628 | 500 |
| Calcium | 96 | 24 | 73 | 37 | 38 | none7 |
| Magnesium | 42 | 8 | 29 | 20 | 13 | none |
| Iron | 3.9 | 0.4 | 0.9 | 0.6 | 2.1 | 0.3 |
| Manganese | 0.08 | 0.03 | 0.03 | 0.03 | 0.04 | 0.03 |
| Chloride | 12 | 44 | 665 | 470 | 128 | 250 |
| Sulfate | 97 | 69 | 10 | 20 | 20 | 250 |
| Fluoride | 0.9 | 0.7 | na | 1.7 | 1.8 | 2 |
| 1. Data on these wells taken from map by A. C. Walker, 1991; General location of each well is shown on Figure 1. | ||||||
| 2. USEPA Secondary Water Quality Standard. | ||||||
| 3. Data not available, or constituent not tested. | ||||||
| 4. Well developed in this formation did not encounter bedrock. | ||||||
| 5. SG--Sand and Gravel; G--Gravel. | ||||||
| 6. Units are parts-per-million (ppm); comments as per Interpreting Your Water Test Report (1988); Total Dissolved Solids: Concentrations above 500 ppm may cause adverse taste and deteriorate domestic plumbing and appliances. Use of water containing 500 ppm is common. Calcium and Magnesium: Main constituents of hardness. Primary concerns with hardness are that more soap is required for effective cleaning, a film may form on fixtures, fabrics may yellow, and scales may forms in boilers, water heaters, and cooking utensils. Iron and Manganese: Iron concentrations greater than 0.3 ppm and manganese concentrations greater than 0.03 may cause brown or black stains on laundry, plumbing fixtures, and sinks. Metallic taste may be present which may affect the taste of beverages made from the water. Chloride: High concentrations may result in an objectionable, salty taste to water, and the corrosion of plumbing in the hot water system. Sulfate: Concentrations in excess of 250 ppm may have a laxative effect on persons unaccustomed to the water. Also affects the taste of water and will form a hard scale in boilers and heat exchangers. Fluoride: At concentrations greater than 1.5 ppm, fluorosis (mottling) of teeth may occur. USEPA Primary Standard is 4 ppm. | ||||||
| 7. No USEPA Secondary Standard. | ||||||
Fulton County's ground-water resources are valuable assets to the county's citizens and industry. The availability and quality of these resources are directly influenced by the properties of the geologic formations underlying the county. The productive sand and gravel formations that underlie the western portion of Fulton County have the potential to provide excellent water adequate for domestic, agricultural, industrial, and many municipal uses. By understanding the physical and chemical nature of these resources, better decisions can be made about ground-water protection, management, and use. This publication provides an overview of the county's ground-water resources. It should be used as a guide, and not as a substitute for detailed information and professional advice when drilling a well.
The Fulton County office of Ohio State University Extension can provide other publications about the county's water resources. Your Extension Agent, the Fulton County Health Department, and Ohio EPA (Northwest District Office, 347 North Dunbridge Rd., Bowling Green, OH 43402) can provide information on well-water testing and drinking-water quality. Your local health department and county Extension office also will be able to provide information about proper well construction and requirements for private water systems. For example, State law requires that each new well constructed must be cased to a minimum depth of 25 feet. The health department issues permits and inspects new well construction.
The ODNR Division of Water--Water Resources Section (Fountain Square, Columbus, OH 43224) is an excellent source of information on ground water. Some of the information in this publication was summarized from the map, Ground-Water Resources of Fulton County, and other information available through the Division of Water. This map is much more detailed than that given in Figure 1, and the Water Resources Section can provide detailed information on ground-water availability and wells. Currently the Water Resources Section is conducting a ground-water pollution potential study for the county. For information, contact the Division. In regard to constructing a new well, the Division maintains a list of the State's registered and bonded well drillers. Hydrogeologists in the Division may be able to provide you with a list of well drillers who are familiar with geological conditions in your area, and provide technical assistance on proper well construction.
An additional excellent source of Ohio ground-water information is the USGS, Ohio District (975 W. Third Ave., Columbus, OH 43212). The USGS has conducted and published a number of ground- and surface-water investigations in Ohio. Additional information on Ohio's geological formations can also be obtained through the USGS, and through ODNR's Division of Geological Survey.
Ground- and Surface-Water Terminology. 1994. L. C. Brown and L. P. Black. AEX 460. Ohio State University Extension.
Ground-Water Resources of Fulton County. 1991. A. C. Walker, ODNR Division of Water. (map).
Interpreting Your Water Test Report. 1988. D. Lundstrom and S. Fundingsland. AE-937, No. 13-AENG-10. North Dakota State University Extension Service.
Nonpoint Source Pollution: Water Primer. 1996. R. Leeds, L. C. Brown and N. L. Watermeier. AEX 465. Ohio State University Extension.
Ohio Ground-Water Quality. USGS National Water Summary--Ohio. 1986. U.S. Geological Survey Water-Supply Paper 2325.
Ohio Ground-Water Resources. USGS National Water Summary--Ohio. 1984. U.S. Geological Survey Water-Supply Paper 2275.
Underground Water Resources (maps of various river basins). 1958-1962. ODNR Division of Water.
Water Resources Data, Ohio, Water Year 1995. Volume 2. St. Lawrence River Basin and Statewide Project Data. 1996. U.S. Geological Survey Water-Data Report OH-95-1.
Water Resources of Fulton County. 1995. G. A. La Barge, K. T. Ricker and L. C. Brown. AEX-480.26. Ohio State University Extension.
Water Testing. 1988. K. Mancl. AEX 314. Ohio State University Extension.
This publication was produced through the Ohio Water Resources Education Project, in cooperation with: ODNR Division of Water; Ohio EPA; USGS, Ohio District; and Ohio Department of Health (ODH). Project leaders are Larry C. Brown and Karen T. Ricker. Partial support for this publication was provided by these cooperating agencies and programs: Ohio State University Extension, Fulton County; Overholt Drainage Education and Research Program; and the Ohio Management Systems Evaluation Area project (USDA CSREES Grant No. 94-EWQI-1-9057).
The project leaders acknowledge the following reviewers: Scott Golden (Environmental Health, ODH); Steve Hindall (USGS, Ohio District); Dave Cashell (ODNR Division of Water); and Tim Fishbaugh (Ohio EPA, NWDO).
A special thanks to Carlos Lopez and Kate Weber (Undergraduate Engineering Assistants) for illustration preparation, and Kim Wintringham (Associate Editor, Section of Communications and Technology, Ohio State University Extension) for editorial and graphic production.
All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status.
Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.
TDD No. 800-589-8292 (Ohio only) or 614-292-1868