Glacial outwash sand and gravel deposits are the principal aquifer in southwestern Langlade County, Wis. The underlying bedrock of pre-Cambrian age contains little or no water. The source of ground water is local precipitation. Information was collected on more than 300 wells in the area. Movement of ground water is generally southward and locally toward streams. Discharge is by streams and subsurface flow. Fluctuations of water levels in wells show a close correlation with seasonal precipitation and with average precipitation over a period of years. Pumping tests made at the city of Antigo's well field gave a coefficient of transmissibility of 62,000 gpd per ft and a coefficient of storage of 0.15 for the outwash deposits. It is estimated that recharge to a 90-squaremile area of the Antigo flats averages about 30,000 acre-feet per year. Of the 1,100 acrefeet pumped from wells in 1948, 69 percent was for municipal supply, 26 percent for rural supply, and 5 percent for irrigation. Use of water for irrigation has caused no measurable decline of water levels in the area as a whole.
