Invasive Species Update - 11/12/2026

Zebra Mussels

This fall of 2026, zebra mussels were discovered in Half Moon Lake on boat lifts. The mussels were taken to Polk County Land and Water, who came to the lake and found more zebra mussels on rocks. Land and Water staff sent pictures to Wisc. DNR, who officially confirmed the presence of zebra mussels in Half Moon Lake. There is no treatment available for these aquatic invasive species, although research is ongoing.

Find out more about Zebra Mussels on our Invasive Species page.

Eurasian Watermilfoil

The Polk County Circuit Court Judge Anderson, at court hearing on October 1, 2026, remanded the Wisc DNR to review their reasons for 2026 permit denial to treat Eurasian watermilfoil with herbicide, and to present their reasons with better explanations and more details by November 2. The DNR sent another permit denial on Nov. 2. The DNR will meet with our lake board in early December to develop a treatment plan that will be acceptable for both parties. Our goal is to treat the EWM in early summer. Stay tuned for more updates as we navigate this process.

Call or email your board members for questions.

Ice Cam

Live status of ice on Half Moon Lake. Cam located on the west shore in the middle of the lake.

Instagram Feed

Follow at: @HalfMoonLakeWI

Micro Blue Moon rising over the lake Saturday night.

BOAT PARADE - 2pm - Decorated boat parade around lake. Gather in Breezy Bay at south end to begin. FIREWORKS - 10pm - Public Beach - watch from the beach or your boat. If inclement weather - Fireworks will be determined at the time of the event. Fireworks might be shot off in a light rain or may delay them slightly, while lightning or heavy rain will cancel them. Rain delay would be Sunday July 5th.

Still and foggy morning at Half Moon. Four loons spotted. Two on the north end, one in the middle, and one on the south end.

The Polk County Land and Water Resources Department is excited to launch the Polk County Boating Viewer which can be accessed at: - Half Moon Lake Website - Helpful Links Page This interactive map allows users to visualize the State of Wisconsin slow no wake regulations, permitted buoys marking hazards, and areas suggested by lake organizations for enhanced wake activities. The map also includes Polk County ramp and carry-in boat access locations. The site includes: Boat landings: includes lake name, type, lanes, surface, dock, parking, restrooms Waterbodies: includes lake name, max depth, class, acres, and shoreline miles Slow no wake areas 100 foot buffer from shore: State regulations require all watercraft to be slow no wake within 100 feet of shore, dock, raft, pier, or restricted area 200 foot buffer from shore: State regulations require personal watercraft to be slow no wake within 200 feet of shore Additional slow no wake designations Water hazards marked by buoys (rocks or shallow areas) Not all hazards are marked by buoys or maps; caution should be used when navigating any waterbody as water depths can vary Suggested enhanced wake areas are designated for select lakes These areas have been designated by the lake organization affiliated with the waterbody These areas are suggested to reduce impacts on the lake This viewer has been designed as an educational resource and is not designed or intended to be used as the only source of navigation.