The state has issued a health alert for toxic blue-green algae at Rockford Lake near Holmesville in Gage County.

Samples taken earlier this week at Rockford Lake were above the state’s health alert threshold of 20 parts per billion (ppb) of total Microcystins (a toxin released by certain strains of blue-green algae.)

Signs are being posted to advise the public to use caution, and the swimming beach at the lake will remain closed during the health alert. Recreational boating and fishing are permitted at the lake, but the public is advised to avoid activities that could involve accidental ingestion of water. People can still use the public areas for camping, picnics and other outdoor activities.

Weekly sampling has been conducted at 46 public lakes in Nebraska since the beginning of May. The lakes will continue to be monitored weekly throughout the 2009 recreational season. Sampling results for toxic algae and bacteria will be updated every Friday and posted on NDEQ’s web site, https://dee.nebraska.gov/home.

(For more information about potential health effects of toxic blue-green algae, what to look for, and steps to avoid exposure, please refer to the Toxic Algae Fact Sheet.)