About the CLWA


SICON LLC reports on 2016 swimmer’s itch research program

During the summer of 2016, CLWA contracted with SICON LLC to implement a multi-faceted pilot program of swimmer’s itch research and assessment on Crystal Lake. In September they submitted a report to the CLWA on their season’s work, which includes several important conclusions:

  • Avian Schistosome Species Assessment

Only one species of snail (Stagnicola emarginata) harbors the SI parasite. The primary waterfowl carrying SI parasites is the common merganser.

  • Whole-Lake Snail Infection Rate Assessment

The severity of SI presence, as reflected in the infected snails, is generally low in comparison to other northwest Michigan inland lakes for which data exists. However, the ten sites around the lake that were sampled varied widely in the severity of their snail infection rate. The factors that determine this variability have not yet been identified.

The full report is available here. Additional results from lab analyses of cercariae and lake water are expected in the coming weeks.

SICON LLC, led by Dr. Curt Blankespoor from the University of Michigan and Ron Reimink, a biologist, is an organization that carries out research on swimmer’s itch and conducts control programs on inland lakes. It has previously provided effective swimmer’s itch control programs for Glen and Higgins lakes. SICON’s website includes information on swimmer’s itch and control methods and provides a system for reporting SI cases.

CLWA is now evaluating the results of SICON’s 2016 program to decide whether it should be expanded into a broader control program during the summer of 2017.

Map showing sites where SICON collected snail samples.

While the overall quality of the watershed is good, the 450-page plan calls for spending to address such ongoing problems as eroding bridges and culverts. pollution from fertilizers and septic systems, bacterial contamination on public beaches, swimmer’s itch, and the spread of aquatic invasive species. It also recommends protection of resources including groundwater, wetlands, forested slopes and other sensitive sites which can have an impact on water quality.

The WMP was completed through a $162,000 grant to Networks Northwest (formerly the Northwest Michigan Council of Governments) with CLWA as a subcontractor. Partners represented on the Steering Committee included the Grand Traverse Regional Land Conservancy, Conservation Resource Alliance, Benzie Conservation District, Green Lake and Duck Lake Association, Grand Traverse Band of Ottawa and Chippewa Indians, Friends of Betsie Bay, and state and local government agencies. CLWA President Joel Buzzell chaired the Steering Committee, while Hoogterp and Networks Northwest regional planner Scott Gest compiled the maps, data and other plan elements for review by the Steering Committee.

Watershed Planning is a requirement of the federal Clean Water Act. Approval by EPA means that implementation of the plan will be eligible for state and federal grant funding over the 10-year life of the document. The Michigan Department of Environmental Quality endorsed the WMP earlier this summer.

The Betsie River/Crystal Lake Watershed Management Plan may be viewed or downloaded at the Networks Northwest website. Printed copies will be distributed to libraries and township agencies.

Protecting Crystal Lake Now for Generations to Come.

P.O. Box 89 • Beulah, MI 49617
231.882.4001 Tel

The Crystal Lake Watershed Association (CLWA), is a non-profit (501c3) organization.

Photography: Jay Burt and Rick Cosaro

Site by: Rick Cosaro