Hydrologic considerations associated with dredging spring ponds in Wisconsin
Spring ponds (small spring-fed bodies of water) are natural features of some glaciated areas and have a continuous flow of ground water entering through their bottoms and exiting through surface outlets.
Dredging has been used to restore ponds that have been filled in part or totally by sediment. The purpose of the study was to determine the hydrology of selected spring ponds and the effect that dredging has had on the ponds. Three ponds, Maxwell, Sunshine, and Krause Ponds, in northeastern Wisconsin were studied. Sediments were dredged from Sunshine and Krause Ponds. Maxwell Pond, which was not dredged, was a hydrologic control to aid in distinguishing changes produced by dredging from those that were natural.
Ground water from glacial deposits is the source of most of the water flowing in spring ponds and streams in the study area. Average annual ground-water recharge in the study area is about 13 inches. Ground-water discharge contributed 97 percent of the total flow in the Red River, a typical stream in the study area, during the 1973 water year.
Ground water and surface water in the study area are of a calcium magnesium bicarbonate type. Dissolved-solids concentration ranges from 170 to 250 milligrams per liter. Temperature of ground water discharging into the spring ponds in the study ranged from 6 to 7 Celsius.