Geneva Lake is a large, deep lake—7.6 miles long, with 20.2 miles of shoreline, and reaching 140 feet at its deepest point. It’s the second deepest natural lake in Wisconsin, which means it often takes longer to completely freeze than many other lakes in our area. For any lake to freeze, temperatures must remain below 32°F (0°C) for an extended stretch of time. While Geneva Lake usually does completely freeze, there have been a few winters when it did not. Since record-keeping began in 1862, the lake has frozen as early as November 23 and as late as March 10, with every date in between occurring at least once. If you think the lake won’t completely freeze this winter, you may write no freeze on the entry form. Please remind students: Always check with a trusted adult before going onto any ice to make sure conditions are safe.
Contest Rules:
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Teachers please fill out one form for each classroom.
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Open to all Geneva Lake area students in grades K–8.
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Entries must be submitted online, emailed, or postmarked by Monday, December 22, 2025.
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Prizes will be awarded for first, second, and third place.
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If there is a tie, the winning entry will be determined by the earliest submission date.
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Teachers or families may contact us with any questions.
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HAVE FUN GUESSING THIS YEAR’S COMPLETELY FROZEN OVER DATE!
ICE-ON CONTEST 2025
Our 2025 E. coli testing season has wrapped up for the year, but the Geneva Lake Environmental Agency remains active year-round to protect and study Geneva Lake. Even outside of the summer monitoring season, our staff and partners are hard at work on projects that safeguard water quality, fisheries, and habitat.
Here’s what we’re focused on:
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Algae and water-quality monitoring – expanding use of new sensor technology to detect changes quickly.
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Fishery and habitat projects – supporting cisco survey work and preparing additional fish cribs for installation.
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Invasive species management – monitoring for Starry Stonewort, zebra mussels, and other aquatic invasives.
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Watershed research – tracking nutrient and E. coli sources in tributary streams.
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Education and outreach – working with schools, lakefront associations, and community groups to promote best practices for protecting Geneva Lake.
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Collaboration and planning – coordinating with municipalities, the DNR, and USGS on long-term strategies like lake level monitoring, shoreline protection, and the Geneva Lake Management Plan.
Thank you for supporting our mission. While swimming season may be over, our commitment to Geneva Lake never takes a break.
2025 SUMMER PUBLIC BEACH TESTING
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GLEA provides weekly E. coli testing as a public service but cannot guarantee real-time water safety. These results are a snapshot of water quality, as bacteria levels can shift quickly. It is important to remember the decision on whether to swim is at your own discretion. Use caution, especially with young children or individuals with weakened immune systems.
Check out the boat cleaning stations at Williams Bay, Lake Geneva, Linn, and Fontana launches!
Brought to you by the Geneva Lake Environmental Agency, Villages of Williams Bay and Fontana, the City of Lake Geneva, and WI DNR grant.
CD3 Roadside
Waterless Cleaning System
We encourage you to clean your boat when entering and exiting Geneva Lake to help us stop the spread of aquatic invasive species
A CLEAN BOAT MEANS CLEAN WATERS
Thank you to Ms. Garcia & Katrina, Elizabeth, Julia, and Chris for finding this excellent resource and sharing the importance of lake ecology!
SWIMMERS ITCH
How to stay safe this summer
Swimmer's itch is caused by flatworm larvae that can unintentionally latch onto human skin when looking for a waterfowl host and cause irritation or itchiness. They like warm water at around 72°F. When your skin dries, the larvae will burrow into the skin and eventually die, but this typically results in some uncomfortable itchiness.
WAYS TO TREAT
Don't scratch! Use an antihistamine lotion. Swimmer's itch is rarely serious and will pass in a couple days.
CONTACT US
Tel. 262-245-4532
PO Box 914
Williams Bay, WI 53191
Our Office:
Located in the same building as Dip in the Bay, Ice Cream Shop.
105 N Elkhorn Rd., Williams Bay, WI 53191
Hours: Monday - Friday: 9 AM - 4 PM
Follow Us
Instagram: https://www.instagram.com/gleawi/
Facebook: https: //www.facebook.com/GLEAWI
