Division of Water advises lake users to continue to use caution
Sampling conducted by the Division of Water (DOW) in October found that cyanobacteria cell counts in several Kentucky lakes with user advisories relating to harmful algal blooms (HABs) were below 100,000 cells/mL. The DOW is removing the “caution” advisory for Beaver Lake (Anderson Co.), Greenbrier Creek Reservoir (Montgomery County), Guist Creek Lake (Shelby Co.), Long Run Lake and McNeely Lake (Jefferson Co.), and Reformatory Lake (Oldham Co.). However, as HABs can disappear and recur over a fairly short period the DOW continues to advise people using all natural waters to observe the conditions of the water and avoid contact with waters that appear to have harmful algae growth or other conditions that may indicate contamination of that water.
The World Health Organization has established a recreational waters guideline of 100,000 cyanobacteria cells/ml based on a moderate probability of adverse health effects. This guideline is based on the potential for short-term adverse effects including skin irritation and gastrointestinal illness. If blue-green algae cell counts exceed 100,000 cells/ml, the DOW issues a HAB advisory. When waters return to levels below the advisory level, the DOW lifts the advisory.
Monitoring by the U.S. Army Corps of Engineers (USACE) and the DOW confirmed the presence of potentially harmful algal blooms (HABs), or cyanobacteria at levels exceeding recommended safety thresholds at several lakes in Kentucky. The DOW has issued advisories pertaining to HABs that remain in effect at several lakes including Barren River Lake, Nolin Reservoir, Green River Lake, Rough River Lake, Taylorsville Lake, Willisburg Lake (Washington County); Carpenters Lake (Daviess County); Campbellsville City Reservoir (Taylor County), and General Butler State Park Lake (Carroll County). These lakes remain open to the public. Visitors to these lakes are advised to 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.
Some cyanobacteria produce toxins that may be hazardous to animals and humans. Symptoms of exposure to harmful algae may include gastrointestinal distress 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 a HAB testing protocol for Kentucky lakes as well as public notification procedures when HABs are identified at levels of concern.
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 these advisories 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/.