The HHPLS identified the infiltration potential of the upland areas within the subwatershed as generally medium, with a number of pockets of low potential clayey soils. Because of the organic nature of the soils in the wetland areas, in general infiltration potential there is variable (see Figure 16). The Carver County Water Resource Management Plan and Hennepin County Geologic Atlas classifies those organic soil areas as highly sensitive to aquifer impacts, with the balance of the subwatershed as being of medium to low sensitivity to pollution, and the major wetland areas on the north and in the south as being highly sensitive (see Figure 17).
Much of the northeastern part of the subwatershed as well as Lake Minnewashta itself has been designated a Drinking Water Sensitivity Management Area (DWSMA), and two Wellhead Protection Areas (WHPA) surrounding City of Chanhassen water supply wells are partly within this subwatershed. The City of Victoria also maintains a well in the subwatershed, but a DWSMA and WHPA have not yet been defined for it. The County Well Index has records of about 40 active private, shallow wells within the subwatershed.