SAVOY EXPERIMENTAL WATERSHED
The Site
Project Objectives
1. Development of a fully-characterized, state-of-the-science, field-scale site
2. Provide for evaluation of new instrumental technologies through on-site development, testing, and calibration
3. Provide site for groundwater model validation and verification
4. Assess physical, chemical and biological processes governing flow and contaminant movement through karst terrains
5. Provide site for advanced ground-coupled heat pump engineering and design
History of SEW
The SEW has been operational since 1996, and has a discontinuous but meaningful record of hydrologic, water quality, geologic, and soil characterization studies completed. SEW has served primarily as an applied field-training site and education and outreach center, with an impressive array of infrastructure, studies, and understanding gained from field camps, training courses, field trips, and thesis and dissertation research projects.
Climate
Average annual precipitation in the SEW is 1120 mm with a monthly low of 47 mm in January and a high of 128 mm in May. Winters are short and mild, with brief periods of snowcover and frost with a mean January temperature of 1.1°C. Summers are long, warm, and humid with a mean July temperature of 25.9°C.
Copperhead Spring
Copperhead Spring is located approximately 500 meters south of Langle Spring. At base flow, Copperhead Spring has a flow of only 0.05 cfs but had a peak storm flow of >25 cfs in January 1998. Like Langle Spring, Copperhead Spring is known to capture surface runoff. Greater animal waste inputs in the Copperhead Spring recharge basin may be responsible for the higher phosphorus and nitrogen concentrations (as compared to Langle Spring) observed for this spring.
Site Description
The Savoy Experimental Watershed (SEW) is composed of six separate basins in and surrounding the Savoy Unit of the University of Arkansas’ Department of Animal Science. The SEW is located in the Ozark Highlands where land use is dictated by topograph. The ridge tops and valley bottoms are in permanent pasture and the steep side slopes are in hardwood forest.
Land Use
Poultry production and beef grazing are dominant land uses in the region and poultry litter is the primary nutrient source for forage growth. Soils within the SEW are shallow and stony with low infiltration rates. The underlying bedrock consists of fractured limestone and is responsible for the karst topography. This combination of soil/bedrock properties allows rapid movement of water and contaminants from the soil surface.
Runoff Weir
A combination weir was installed at the Basin 1 outlet in January 1998. Since its installation, only three runoff events have occurred. The low number of runoff events is due to two reasons. First, both Langle and Copperhead Springs intercept flow in the channel within Basin 1. Second, surface runoff from upland pastures infiltrates into the coarse gravel soil at the bottom of Basin 1. Phosphorus typically is transported sorbed onto sediment particles, whereas nitrate is transported in the dissolved phase, and is subject to bioremediation by bacteria in the epikarst
Langle Spring
Langle Spring discharges directly into the Illinois River. This spring is named after the family that lived near it early in the 1900's. Gaging and monitoring equipment were installed on Langle Spring in the summer of 1997. Flow from Langle Spring has varied from <0.2 to >7 cubic feet per second (cfs) since continuous monitoring began. Dye tracing studies have shown that this spring captures surface runoff from Basin 1. Phosphorus and nitrogen concentrations in Langle Spring are generally lower than from Copperhead Spring.