News Release 393

Correction:  Adds Wakonda State Park for geometric mean exceedance and removes Truman State Park's beach, which will be open July 1.

Swimming beaches at four state parks closed this weekend due to elevated E. coli levels

Two additional state park beaches closed due to high water levels

Volume 38-393 (For immediate release)
Contact:  Judd Slivka

JEFFERSON CITY, MO, JUNE 30, 2010 – Swimming beaches at four Missouri state parks will be closed this weekend due to E. coli levels higher than the standard set by the Missouri Department of Natural Resources.

Water samples drawn Monday from the public beaches at Finger Lakes, Thousand Hills, Long Branch and Wakonda state parks showed E. coli levels in excess of the department’s standard for state park beaches.

Finger Lakes State Park beach had 1,119.9 E. coli colonies per 100 milliliters of water. Two other parks had E. coli levels considerably lower than Finger Lakes State Park, but still in excess of the department standard:

Additionally, Wakonda State Park’s recent data, when combined with previous samples, had a geometric mean of 203.3 E. coli colonies per 100 milliliters of water.

Mark Twain and Lewis and Clark state park beaches remain closed due to high water levels.

In order to provide a safer beach experience, the Department of Natural Resources will close a state park beach if a single sample is above 235 mpn/100 mL for E. coli, which is also the U.S. Environmental Protection Agency’s single-sample guideline for a swimming beach.  The department will also close beaches at state parks if the geometric mean for E. coli, which considers previous results in addition to the current week’s results, exceeds 126 mpn/100 mL.

The six closed beaches have been posted with signs notifying visitors of the closure.  The four park beaches with elevated E. coli levels will remain closed until they fall below the department standard. The two park beaches closed due to high water will remain closed until the water levels have receded.

No other state park beaches tested high for E. coli levels; however, bacterial levels often rise after heavy rains and lake users should use their judgment when swimming after heavy rains.

The latest information on beach closings at state parks is available online at Additional beaches may be closed for other reasons, such as high water levels or safety and management issues. Information about all temporary closings at state parks is available online at /asp/spbeaches/state-park-beach-status.asp.

The 1,128-acre Finger Lake State Park is located in Boone County. Thousand Hills State Park, which is 3,079 acres surrounding Forest Lake, is located in Adair County. Long Branch State Park, which is 1,828 acres surrounding Long Branch Lake, is located in Macon County.

The Missouri Department of Natural Resources, through its Division of State Parks, manages 85 state parks and historic sites throughout the state, including 15 with swimming beaches. Water samples are taken weekly during the recreational swimming season to help ensure a safe public swimming area.

E. coli is a bacteria found in the intestinal tract of warm-blooded animals, including humans.  While most strains of E. coli are harmless, some strains can cause gastrointestinal illness. 

These bacteria and other pathogens can reach lake water from many different sources, both human and animal.  For some people, such as children, elderly or those with weakened immune systems, even low levels of these bacteria may cause illness.