The Necedah National Wildlife Refuge (NNWR), in Juneau County, Wisconsin (fig. 1). contains extensive wetlands areas commonly recog- nized as providing habitat and protection for migratory birds and endangered species. Because of concerns with potential changes to the water resources that supply the Refuge, the U.S. Fish and Wildlife Service and the U.S. Geological Survey undertook a one-year study to characterize the water resources of the Refuge in 1998. That study, which focused on quantifying the surface water and ground-water flows into and out of the Refuge, was intended to serve as a baseline condition of water resources on the Refuge.