The Nebraska Department of Environment and Energy (NDEE) and its partners have begun weekly sampling for harmful algal blooms (HABs) at Nebraska’s public lakes.

Between May and September, the state tests for HABs at 53 public lakes each week to protect public health. HABs, also referred to as toxic blue-green algae, refer to certain strains of cyanobacteria that produce the toxin microcystin. HABs are caused by a combination of factors: water temperature, low water depths and high levels of nutrients like nitrogen and phosphorus.

Microcystin can cause skin rashes, lesions or blisters when it comes in contact with skin. More severe cases may cause ulcers inside the mouth or nose; eye or ear irritation; and blisters on the lips. Symptoms of ingestion can include headaches, nausea, muscle pains, abdominal pain, diarrhea and vomiting. Severe cases could include seizers, liver failure and respiratory arrest. Though death in humans is rare, pets and farm animals have died from drinking water containing an HAB.

If test results show microcystin at 8 parts per billion (ppb) or more, NDEE, in partnership with the Nebraska Department of Health and Human Services (DHHS), will issue a health alert. When a lake is under a health alert, designated swimming beaches are closed and signs are posted at the beach to advise the public to use caution. Beaches remain closed until the lake tests below 8 ppb of microcystin.

Recreational boating and fishing are still permitted while a lake is under a health alert, but the public is advised to use caution and avoid exposure to the water. Do not let pets in the water or drink from the lake. People can still use the public areas for camping, picnics and other outdoor activities.

HABs can impact more water bodies than lakes. Here are signs of HABs to watch out for if farmers or ranchers suspect an HAB at a cattle drinking water source:

• Water that has a neon green, pea green, blue-green or reddish-brown color;
• Water that has a bad odor;
• Foam, scum or a thick, paint-like appearance on the water surface;
• Green or blue-green streaks on the water surface; and
• Areas with algae that look like grass clippings floating on water.

It’s also important to note that protected bays and shorelines on the windward side of the lake generally have higher concentrations of algae and potentially toxins.

To report a suspected HAB, please contact NDEE’s surface water unit at (402) 471-0096, (402) 471-2186, or at ndee.beachwatch@nebraska.gov.

If you are experiencing health symptoms, first notify your physician. Also report these symptoms to the Nebraska Department of Health and Human Services at (402) 471-0510. You can also contact the Nebraska Regional Poison Center at 800-222-1222 for more information.

In addition to posting signs when a lake is on health alert, NDEE and DHHS issue press releases and post information to their social media accounts. NDEE also has a listserv, where those interested can sign up to receive health alerts directly to their emails. Those interested can subscribe by sending an email to listserv@listserv.nebraska.gov with “SUBSCRIBE DEQ-BeachWatch (your name)” in the body of the message. Leave the subject line blank. You will receive an email to confirm your request. Once you confirm by clicking the link, you will be added to the listserv. To unsubscribe, send an email to listserv@listserv.nebraska.gov. In the body of the message, type “SIGNOFF deq-BeachWatch.”

NDEE’s sampling partners include the Central District Health Department, Nebraska Public Power District, Upper Republican Natural Resources District, Lower Republican NRD, South Platte NRD, Middle Niobrara NRD, Lower Loup NRD, Nemaha NRD, Lower Elkhorn NRD and the United States Army Corps of Engineers.