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Hydrogeology of Harrison County, Indiana

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Hydrogeology of Harrison County, Indiana HYDROGEOLOGY OF HARRISON COUNTY, INDIANA BULLETIN 40 STATE OF INDIANA DEPARTMENT OF NATURAL RESOURCES DIVISION OF WATER 2006 HYDROGEOLOGY OF HARRISON COUNTY, INDIANA By Gerald A. Unterreiner STATE OF INDIANA DEPARTMENT OF NATURAL RESOURCES DIVISION OF WATER Bulletin 40 Printed by Authority of the State of Indiana Indianapolis, Indiana: 2006 CONTENTS Page Introduction................................................................................................................................ 1 Purpose and Background ........................................................................................................... 1 Climate....................................................................................................................................... 1 Physiography.............................................................................................................................. 4 Bedrock Geology ....................................................................................................................... 5 Bedrock Topography ................................................................................................................. 8 Surficial Geology....................................................................................................................... 8 Karst Hydrology and Springs..................................................................................................... 11 Hydrogeology and Ground Water Availability.......................................................................... 15 Unconsolidated Aquifer Systems................................................................................... 17 Unglaciated Southern Hills and Lowlands Aquifer System .............................. 17 Alluvial, Lacustrine, and Backwater Deposits Aquifer System ........................ 19 Ohio River Outwash Aquifer System ................................................................ 19 Ohio River Outwash Aquifer Subsystem........................................................... 20 Unconsolidated Aquifer Systems Registered Significant Ground-Water Withdrawal Facilities ........................................................................................ 20 Bedrock Aquifer Systems .............................................................................................. 20 Mississippian -- Buffalo Wallow, Stephensport, and West Baden Groups Aquifer System .................................................................................................. 23 Mississippian -- Blue River and Sanders Groups Aquifer System.................... 24 Mississippian -- Borden Group Aquifer System................................................ 24 Bedrock Aquifer Systems Registered Significant Ground-Water Withdrawal Facilities ........................................................................................ 25 Ground Water Levels and Potentiometric Surface .................................................................... 25 Ground Water Quality................................................................................................................ 26 Summary.................................................................................................................................... 29 References Cited ........................................................................................................................ 31 Appendix Surface Water Quality Data....................................................................................................... 34 FIGURES Page 1. Location of Harrison County............................................................................................... 2 2. Harrison County Physiography ........................................................................................... 3 3. Bedrock Geologic Map of Harrison County ....................................................................... 6 4. Bedrock Topography Map of Harrison County .................................................................. 9 5. Harrison County Generalized Cross Section from Southwest to Northeast........................ 10 6. Unconsolidated Deposits Thickness Map of Harrison County ........................................... 12 7. Quaternary Geologic Map of Harrison County................................................................... 13 8. Ground-Water Flow and Dissolution Features of Carbonate Rocks................................... 14 9. Cross Section Illustrating the Underground Capture of Indian Creek ................................ 15 10. Residual Drawdown of a Test Well Screened in Outwash Sand and Gravel ..................... 16 11. Unconsolidated Aquifer Systems Map of Harrison County ............................................... 18 12. Bedrock Aquifer Systems Map of Harrison County........................................................... 22 13. Hydrograph of Observation Well Harrison 8...................................................................... 25 14. Map Showing Composite Ground-Water Level Surface of Harrison County.................... 27 TABLES 1. Normal Monthly Maximum, Minimum, and Mean Temperatures for the Period 1971-2000 ............................................................................................................................ 4 2. Normal Monthly and Annual Precipitation for the Period 1971-2000 and Precipitation Extremes for the Period 1901-2001 ..................................................................................... 4 3. Stratigraphic Column and Exposed Bedrock Thickness for Harrison County.................... 7 4. Registered Significant Ground-Water Withdrawal Facilities in Harrison County ............. 21 5. Ground Water Chemistry Data and USEPA (2006) Drinking Water Standards for Constituents Reported.......................................................................................................... 28 INTRODUCTION Harrison County is located in south-central Indiana (Figure 1) and is bounded by Floyd County to the east, Washington County to the north, and Crawford County to the west. It is bordered on the southeast, south, and southwest by the Ohio River. Harrison County covers an area of approximately 485 square miles and had a year 2000 population of 34,325 (U.S. Census Bureau, 2005). The main population center is Corydon (2000 population 2,715), which is the county seat. The next largest towns are Palmyra (2000 population 633) and Lanesville (2000 population 614). Milltown (2000 population 932), which is situated on the Crawford and Harrison county line, had a 2000 Harrison County population of about 400. Ground water availability in Harrison County is highly variable because of the nature of the bedrock and unconsolidated deposits. Reported well yields range from less than 1 gallon per minute (gpm) to 1,000 gpm. The most productive wells are located in the glacial outwash deposits of sand and gravel within the Ohio River valley. The other main sources of ground water in the county are the bedrock aquifers, which are primarily limestone. PURPOSE AND BACKGROUND The purpose of this report is to present existing information on the geology, ground-water availability, and ground-water quality of Harrison County. Information came from published and unpublished reports, water well records, and ground-water quality data on file at the Division of Water (DOW). Unpublished reports on the ground-water resources of Harrison County by William J. Steen, retired DOW geologist, and J.D. Hunn of the U.S. Geological Survey were invaluable. A special thanks is owed to Dr. W. Thomas Straw, Ph.D. Indiana University, and professor emeritus Western Michigan University, for a discourse of his Ohio River Valley mapping dissertation (Straw, 1968). Since 1959, an Indiana state law has required water well drillers to submit to the Division of Water a record, or log, for each well drilled in the state. The well logs provide information on stratigraphy, aquifer zones and depths, ground-water levels, and ground-water availability. Approximately 1,000 records (670 field-located) of water wells drilled in Harrison County were reviewed for this study. The wells are fairly evenly distributed across the county (Figure 2). The vast majority (over 97%) of the wells were drilled into bedrock. Less than 3% of the wells were completed in unconsolidated materials. The data from the well logs were used to evaluate ground- water availability, ground-water levels, and the direction of ground-water flow. CLIMATE Long-term climatic data for Harrison County shown below are based on the Paoli, Indiana weather station (Midwestern Regional Climate Center, 2005). Normal monthly maximum, minimum, and mean temperatures for the period 1971-2000 are listed in Table 1. Air temperatures reach a high point in July with a monthly mean of 75.5 °F and dip to a mean of 28.2 °F in January. Precipitation averages nearly 48 inches per year. Normal monthly and annual precipitation for the period 1971-2000 and precipitation extremes for the period 1901-2001 are listed in Table 2. 1 Figure 1. Location of Harrison County. 2 R 2 E R3E R4E Blue T 1 S River T 2 S Crawford Upland R5E T 3 S Mitchell Plateau Blue River Norman Indian Upland Creek T 4 S Ohio Ohio River River Buck Creek T 5 S Mosquito Creek T 6 S Figure 2. Harrison County Physiography (adapted from USGS topographic maps and Gray, 2000). 3 Table 1. Normal Monthly Maximum, Minimum, and Mean Temperatures for the Period 1971-2000 [values, in degree Fahrenheit
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