From recommendations by the World Health Organization and many years of data and statistical analyses, KDHE has established the following recommendations for three advisory levels: Watch, Warning, and Hazard. However, Kansans should be aware that blooms are unpredictable. They can develop rapidly and may move across a lake due to wind or other hydrologic processes, requiring visitors to exercise their best judgment. If there is a surface scum or paint-like surface, or if the water is bright green, avoid contact and keep pets away. These are indications that a harmful bloom may be present. Remember, "When in doubt - stay out!"