E. coli

May 25, 2023

Several years ago, I blogged on the meaning behind Memorial Day as an American holiday observed on the last Monday of May honoring the men and women who died while serving in the US military to remember their service.  Following the American Civil War this was known as Decoration Day, but the name was changed to be Memorial Day, and was made a federal holiday in 1971.  The day has officially set aside to honor veterans, but many Americans observe Memorial Day as a time to visiting cemeteries or hold memorials to remember family members.  This day also marks the unofficial beginning of the summer season and like most American holidays, this morphed into Memorial Day Weekend.  Our State and Federal Parks are booked well in advance as families and friends come together for camping, fishing, boating, and swimming in the pristine Arkansas lakes.  However, the big news in northwest Arkansas this last week has been the discovery of E. coli contamination in one of the area’s large lakes.   

When I looked online, I found E. coli is a bacterium that originates from the waste of animals or humans.  High numbers of E. coli in a pond could come from septic systems, runoff from barnyards, or from wildlife (especially waterfowl).  Ponds and lakes used for swimming and other recreation should have less than 126 colonies of E. coli bacteria per 100 mL (3.4 oz) of water.  High levels of E. coli bacteria can be reduced by limiting animal access to the pond, maintaining nearby septic systems, and redirecting runoff from barnyards and other areas where animal waste accumulates.  The parks have taken restrictive measures to reduce their use by domesticated animals and do not allow feed lots in their vicinity.  The problem appears to be the large number of waterfowl that migrate through the area during the spring.  This is compounded by the Canada geese (Branta canadensis) who nest at the lake.  Swimming in water with high levels of E. coli can make you sick causing nausea, vomiting, and fever.

Beaver Lake is managed by the US Army Corps of Engineers (USACE) and they announced the closing of three beaches on the lake due to “higher than acceptable E. coli levels.”   The USACE does baseline testing at the beginning of the year and test before each of the major holidays to make sure the swim beaches are safe.  Large amounts of rain (like we have been having) can wash the shore fecal matter into the lake and create unsafe conditions.  Beaver Lake has a total of 14 swimming beaches and the Corps only tests those areas.  Three of the swimming beaches at Beaver are closed for E. coli and the beach at Horseshoe Bend is closed because of high water.  The Corps says they must get two consecutive tests back indicating the water is safe before reopening a swimming beach. The Corps took a water sample on Monday and another Tuesday in hopes of reopening the swimming beaches in time for the weekend.  As of today, at 3:16 pm, after tests showed acceptable E. coli levels for the beaches, they have been reopened.  Apparently Memorial Day Weekend has been saved.

Thoughts:  The Environmental Protection Agency (EPA) develops criteria to protect people from viruses and bacteria and their associated toxins in water bodies.  State and tribal governments “can use” the recommended criteria as guidance when setting their own water quality standards to protect human health.  The problem with trying to protect people is the way levels of contaminants are determined to be acceptable.  An acceptable level does not mean the contaminant does not exist, but confirms the contaminant is present.  Studies are conducted to determine the amount of contaminant that is the acceptable limit.  I am not sure how different the effects will be if there are 125 colonies of E. coli rather than 126.  At least now we can all swim safely.  Act for all.  Change is coming and it starts with you.