Virginia Water Science Center
Project Information Title: Number: Location: Cooperating Agencies: Project Chief: Period of Project: USGS IN YOUR STATEUSGS Water Science Centers are located in each state.
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Bedford County Monitoring NetworkProblem Bedford County consists of 764 square miles in the west-central portion of Virginia's central plateau. Its boundaries include the Blue Ridge Mountains on the west, the James River on the northeast and Smith Mountain Lake on the south, and Campbell County on the east. The area has a rolling to hilly terrain with elevations from 800 feet to 4,200 feet above sea level. The County contains the headwaters of Goose Creek and Big Otter River, which are major tributaries to the Roanoke River. The County is underlain by fractured-rock aquifers that are increasingly being relied upon to supply water to local communities, industry, and individual residences. This is an area with an expanding economy and a growing population, and, to meet future water needs, these aquifers are likely to be developed to supplement current withdrawals. As urban and rural growth continues, competition for clean water may increase in areas previously capable of meeting local water-use demands. Objectives: The USGS Virginia Water Science Center is beginning to characterize streamflow statistics in the region and the fractured-rock aquifer systems in the County by initiating relevant, long-term, hydrogeologic data collection, which will provide information that can be used to guide the development and management of the water resources within the County. Approach: In 2006, there were two, real-time, continuous-record, surface-water gaging stations that monitored basins within the County: Station 02059500—Goose Creek near Huddleston, Va., operated by the Virginia Department of Environmental Quality, in operation since October 1930. Drainage area of 188 mi2. Station 02061500—Big Otter River near Evington, Va., operated by the Virginia Department of Environmental Quality, in operation since April 1937. Drainage area of 320 mi2. Information on the availability of groundwater in an area can be derived from estimates of recharge to the groundwater system and estimates of water entering and leaving a basin. Rates of effective groundwater recharge can be estimated using streamflow data from continuous-record, surface-water gaging stations and hydrograph-separation techniques that separate streamflow into groundwater (base flow) and surface-runoff components. With a knowledge of precipitation in a region, water budgets (estimates of water entering and leaving a basin), can also be derived. As of December 2006, the USGS had installed two additional, real-time, continuous-record, surface-water gaging stations: Station 02059485—Goose Creek at Rt 747 near Bunker Hill, Va. Drainage area of 125 mi2. Station 02061000—Big Otter River near Bedford, Va. Drainage area of 114 mi2. Additionally, partial-record surface-water gaging (stations where discrete discharge measurements are obtained over a period of time) can often be correlated to concurrent daily mean discharge at nearby continuous-record gaging stations by graphical regression methods. Streamflow statistics and mean base-flow discharge can be estimated for the partial-record surface-water gaging stations from this correlation. Rates of effective groundwater recharge can then be estimated. Therefore, beginning in December 2006, the USGS established 12 partial-record surface-water gaging stations in the Big Otter and Goose Creek Basins to monitor these streams:
This combination of continuous-record and partial-record surface-water gaging stations provides areal coverage of the Big Otter and Goose Creek Basins, and also provides base-flow information on the underlying types of bedrock in these basins. This data-collection approach covers the majority of the County and will serve as a strong foundation for future water-resources investigative efforts. Finally, in May 2008 the USGS in cooperation with the Virginia Department of Environmental Quality, sited, drilled, and instrumented three real-time observation wells in the County to monitor water levels:
Relevance and Benefits: The data collected as part of this study will contribute to the knowledge of water resources in the fractured-rock aquifers of Bedford County and the southwestern Piedmont and Blue Ridge Physiographic Provinces of Virginia. The study will set the framework for further investigation of fundamental processes controlling the occurrence and movement of water in the siliciclastic and crystalline aquifer system of the region. |