Clark Lake and its watershed are located in the Door County towns of Jacksonport, Sevastopol and Egg Harbor. The recent history of declining bulrush beds and other aquatic vegetation coupled with less successful fishing and more boating traffic led many lake residents to push for a comprehensive study of the lake conducted by UW Stevens Point Center for Watershed Science and Education (CWSE) in partnership with Clark Lake Association (CLA), Wisconsin Department of Natural Resources (DNR), Door County and The Ridges Conservancy.

Presentation by the Center for Watershed Science and Education at the University of Wisonsin-Stevens Point about the studies that are contributing to the strategic plan for Clark Lake. Lists recommended actions that were brought up through the multiple studies done.

This study combined boating experiments and continuous turbidity measurements with applied wave theory and sediment analysis to evaluate the mechanisms contributing to the resuspension of sediment in Clark Lake in Door County.

The purpose of this study was to determine the density and areal extent of bulrush (Schoenoplectus acutus) beds in Clark Lake. The data may serve as a baseline which can be used to determine the extent of future changes in density and area of bulrush beds. The methods used to determine bulrush density are intended to be easily transferable to Lake Association volunteers to be performed in future years.

All of the areas around Clark Lake that are identified in this document play a role in supporting the lake’s ecosystem. However, in addition to taking action to protect these areas efforts should be made to improve conditions in the riparian area of the lake. As a first step riparian land use around the lake should be consistent with the rules in the county zoning ordinance.

Clark Lake receives water from precipitation on the lake, runoff directly into the lake, groundwater discharging to the lake, and water flowing from Logan Creek. It is important to know the land area that contributes this water to evaluate the impact of future land management changes. In this report, the delineation of a contributing area for Clark Lake is described.

The aquatic macrophyte community of Clark Lake is characterized by good species diversity, good quality, and abundant frequency of plants and low density of growth. In 2006 a total of 60 species of aquatic plants were identified in Clark Lake and upstream Logan Creek to Highway 57 (Appendix 1). Not all species were present in line/transect sample sites but are included and noted as existing in Clark Lake.

Macroinvertebrate bioassessment samples were collected from Logan Creek, Door County, Wisconsin on May 15 and October 12, 2005 by Dr. Stanley W. Szczytko and Jeffrey Dimick from the University of Wisconsin/Stevens Point. An attempt was made to sample Logan Creek from near the headwaters at Lost Lake to near the outlet at Clark Lake. Sites were selected using criteria established by Hilsenhoff (1987) and used routinely by the Wisconsin Dept. of Natural Resources for rapid macroinvertebrate bioassessment sampling.

The Ridges Sanctuary in cooperation with the Clark Lake Association proposes to conduct water quality and biotic evaluation and strategic planning in the Clark Lake watershed in Door County. The project elements and deliverables are specified in the grant application materials submitted January 30, 2005. Phase 1 of the study will include lake and river water quality sampling, stream flow measurements, macroinvertebrate sampling, coordinator, and faculty associated with overall study, macroinvertebrate and fishery study components.