Water quality

Water quality

Invasive species

Our first defense against invasive species in our water is to use a self-wash power spray located at the DNR’s boat ramp on Little Glen.

Our invasive species prevention helps prevent the introduction of the quagga mussel, coltsfoot, the spiney water flea, the fishhook water flea, the round goby, the rusty crayfish, viral hemorrhagic septicemia (VHS), Eurasian watermilfoil, starry stonewort, and hydrilla to mention a few.


colts-foot-early-spring-flowersColtsfoot (Tusilago farfara), a vicious foreign invader, was first found on the shores of Big Glen Lake in 2008. Since then, it has spread rapidly along the shoreline and now is found throughout the shoreline from Brooks Lake to Inspiration Point-a four-mile area. It quickly wipes out native herbaceous plants as it invades shorelines, lawns, and neighboring fields. It’s easiest to identify in early spring when a bright yellow flower appears atop of plant stems as seen in the picture to the left.  It may poke its head up through snow as early as mid-March. Deadheading these blossoms is the first line of defense and helps prevent further spread of the plant through seed heads easily carried on wind to new locations.

colts-foot-mid-summer-leavesMid-summer leaves as shown to the right are large, up to 7 inches wide, hoof-shaped with angular teeth on the margins. The creeping, underground rootstalks may lurk as deep as 10 feet. They preserve their vitality for a very long period and a small piece may send up foliage after many silent years underground. Attempting to eradicate by digging is not encouraged.

Landowner manuals

Septic System Guide for Empire Township

Landscaper Guidelines

Glen Lake-Crystal River Landowners Handbook

Discovery Boat

Happy Discovery BoatThe Discovery Boat Program (formerly the “Schoolship Program”) provides a hands-on educational opportunity for anyone to join Rob Karner, watershed biologist, and his assistants Laura Wiesen and Joe Blondia to come aboard a 22-foot pontoon boat on Glen Lake.

During the two-hour cruise on Glen Lake, you’ll discover many of the secrets of how and why Glen Lake is so unique and pristine. Many say Glen Lake is one of the most beautiful inland lakes in the country and we will explore the many reasons why.

The curriculum varies each week and is tailored to the interests of the participants of each session. Topics range from discovering how the glaciers form the lake and surrounding hillsides, wetlands, and streams to the chemistry of the water to the biology of the plants and animals, to the ecology of how all the parts work together and finally, how the political forces are at work within our watershed. The life cycle of swimmer’s itch and how to prevent getting it will also be covered.

Discovery Boat activities during the cruise include making visual observations, reading the water clarity measurements, analyzing chemical properties using the hydrolab, taking bottom samples of the lake with a mini-dredge, doing a plankton tow, bringing up from the lake bottom aquatic plants and animals for identification and more.

Register and pay using our easy online process. Reservations are on a first-come, first-served basis.

Cost is $10 per person for members of the Glen Lake Association and the Glen Lake Yacht Club, and $25 per person for all others.

Children under 5 years not allowed. Children 5-10 years must be accompanied by a parent or guardian. If possible, please bring life jackets for children. Click Here to download the liability release form which is required for all participants.

Normally, sessions are scheduled on Fridays in the mid-morning and a second session in the early afternoon from mid-June to mid-August. GLA reserves the right to cancel due to weather conditions. Trip departs from the Glen Craft Marina boat slips. Please arrive 15 minutes prior to starting time.

Underwater image smallShoreline Management

Our Shoreline Management program is organized by the Water Quality Committee. The purpose is to protect our beautiful lake and has three major segments to its focus:

  • Property Maintenance – Suggestions on how to maintain your lake front property, so as not to damage the lake;
  • Cladophora Studies — Measuring the extent of damage to the lake by pollutants entering into the lake from surrounding surfaces;
  • Shoreline Surveys — Analysis of individual pieces of property to reduce/eliminate contaminate intrusion into the lake, by making suggestions on alternations in landscaping as well as septic maintenance.
  • Fertilizer — The Glen Lake Association has recommendations (in order of importance) for riparians who wish to add nutrients to their lawns and landscape.

Score your own shoreline using this survey.