Question for Craig Johnson

[Jim C.]

How long of a time frame does the Blue-Green Algae Warnings and Advisories stay infect. When they put an Advisory for a lake or body of water. Is it just while the bloom is on or is there other things that make it go away. With much needed rain we had & cooler temps will that help. Thanks Jim C.

[Craig Johnson]

How long of a time frame does the Blue-Green Algae Warnings and Advisories stay infect. When they put an Advisory for a lake or body of water. Is it just while the bloom is on or is there other things that make it go away. With much needed rain we had & cooler temps will that help. Thanks Jim C.

Jim,

Duration of the Warnings/Advisories can vary from lake to lake and bloom to bloom. Several factors figure in to the strength and longevity of a blue-green algae bloom. KDHE takes samples from waters affected with blue-green algae on a weekly basis. These samples are analyzed and a blue-green algae cell count is obtained. It is dependent upon this cell count as to whether the lake is listed under a Warning or an Advisory. The 'bloom' may last most of the growing season like some of the smaller Kansas lakes have endured and some can come and go in just a couple of days. Cooling weather, shorter days, increased wind action, decreased water clarity, cloudy days, and decreased lake nutrient levels all can contribute to reduced densities of blue-green algae. How long the bloom actually lasts is determined by the availability of conditions favorable to producing the bloom, especially high levels of nutrient enrichment. Once 'the fuel' is gone from the waterbody, the bloom will burn itself out.