Officials issue these alerts when testing finds a toxin produced by certain harmful algal blooms. Boating and fishing remained permitted, though visitors were strongly advised to minimize direct water contact and avoid swallowing any lake water. Recreational boating and fishing were still allowed, but visitors were cautioned to limit water exposure and take extra care not to ingest any lake water. Other Nebraska Lakes That Saw Alerts This SummerBeyond the four lakes that drew significant attention, several other Nebraska water bodies also faced harmful algal bloom advisories or alerts during the summer of 2026. The pattern across these locations reflects just how widespread algae bloom activity can be during a warm Nebraska summer.