Potentially Harmful algal blooms identified in several Kentucky lakes

Division of Water advises lake visitors to make informed decisions

The Kentucky Division of Water (DOW) and the U.S. Army Corps of Engineers (USACE) have confirmed the presence of potentially harmful algal blooms (HABs), or cyanobacteria at levels exceeding recommended safety thresholds at several lakes in Kentucky. These lakes include Barren River Lake, Nolin Reservoir, Green River Lake, Rough River Lake, Taylorsville Lake and Greenbriar Creek Reservoir in Montgomery County. Cell counts at one site at Taylorsville Lake exceeded 1,000,000 cells/ml. The World Health Organization has determined that “moderate probability of experiencing adverse health effects” exists when cyanobacteria cell counts exceed 100,000 cells/ml. The Department of Public Health, the Kentucky Department of Fish and Wildlife, the Department of Parks, and other stakeholders have been informed of these conditions.

These lakes remain open to the public. Visitors should be aware of the potential health issues and take precautions.

The following guidelines are recommended to avoid exposure to HABs:

• Direct contact with affected water, including swimming, wading, fishing, paddling, diving and water skiing may result in symptoms. It is advisable to avoid contact with water that has unusual color or where blue-green bacteria have been identified, even if the water appears to be clear.
• People who are prone to respiratory allergies or asthma should avoid areas with harmful algal blooms. Children may be particularly sensitive.
• If contact has been made with water containing blue-green algae, wash off with fresh water. In some cases, skin irritation will appear after prolonged exposure. If symptoms persist, consult your local health care provider.
• Fish fillets (not organs) may be consumed after the fillets have been rinsed in clean, non-lake water. It is advisable to wash any parts of your body that have come into contact with the fish.
• Prevent pets and livestock from coming into contact with HAB-infested waters.

Kentucky lakes investigation – HAB cell counts

Some cyanobacteria produce toxins that may be hazardous to animals and humans. Symptoms of exposure to harmful algae may include gastrointestinal symptoms such as stomach pain, nausea, vomiting and diarrhea; skin and eye irritation; and/or throat irritation or breathing difficulties.

If you are concerned that you have symptoms that are a result of exposure to HABs, please see your doctor and call your local health department.

DOW has been working with a number of agencies to develop an HAB testing protocol for Kentucky lakes as well as public notification procedures when HABs are identified at levels of concern. The protocol will consist of mechanisms to perform monitoring and to issue “advisories” when cell counts exceed 20,000 cells/ml and “cautions” when they exceed 100,000 cells/ml at affected lakes.

Last year, USACE began monitoring USACE-owned lakes in Kentucky for the presence of cyanobacteria. At that time, the USACE identified excessive levels of cyanobacteria in several reservoirs, prompting USACE to issue public warnings to avoid or minimize human and animal contact with algae-infested waters. The DOW subsequently began monitoring several lakes in Kentucky and identified excessive levels of cyanobacteria in several lakes, which similarly prompted the DOW and USACE continue to monitor lakes in Kentucky. The DOW has developed a predictive model for identifying HAB conditions in Kentucky lakes using available satellite data. The DOW and USACE are working collaboratively to calibrate that model so that it may be used to inform the division of all lakes regardless of whether there is water quality data available from the lake.

Better known as blue-green algae, cyanobacteria occurs naturally in the environment. Environmental conditions, including excess phosphorus and nitrogen, sunny conditions, warm temperatures and low-flow or low-water conditions — contribute to the rapid reproduction and spread of the algae in a waterbody. The more typical green algae, which are not harmful to humans or animals, come in many forms and may appear as underwater moss, stringy mats or floating scum.

Cyanobacteria, on the other hand, appear as slicks of opaque, bright-green paint, but closer inspection often reveals the grainy, sawdust-like appearance of individual colonies of bacteria. The color of the algae may also appear as red or brown.

Peter Goodmann, Director of the DOW, said it is important to understand that the issuance of advisories and cautions are intended to educate potential users about the water bodies so that they may make informed decisions.

Public water systems depending on lakes for their raw water source should consider monitoring for the presence of HABs and adjust treatment of the water accordingly. Algal blooms are easily addressed through water treatment techniques, and the water produced from these sources is safe to drink.

The presence of excess nutrients in the waterbody can cause algal blooms. Proper management of nutrients from various sources of stormwater runoff in the watershed and proper treatment of nutrients in wastewater play a key role in managing algal blooms of all kinds. The Division of Water, with other federal and state agency partners and numerous stakeholder groups, is developing a Nutrient Reduction Strategy to address nutrient pollution problems in Kentucky.

For information on harmful algal blooms and updates on the levels at USACE lakes, visit: http://www.lrl.usace.army.mil/Missions/CivilWorks/WaterInformation/HABs.aspx

For more information on safe water recreation, visit: http://www.who.int/water_sanitation_health/bathing/srwe1/en/.