Starting April 1, Jackson County Parks and Recreation began running weekly water sample tests from local recreational lakes through October 31. Samples are submitted to an independent, third party laboratory to identify levels of all types of e. coli. The Environmental Protection Agency standard of 235 CFU/ 100 mL is used as the threshold for posting warning signs to alert residents and users.
There are many different types of e. coli, many of which are harmless. Very few can cause illness and even fewer can be life threatening. These samples are tested for all strains of e. coli. Test results are reported in “## CFU/ 100 mL” measure, which translates to “the number of Colony Forming Units per 100 milliliter” of sample.
A high e. coli count does not necessarily mean there is bad e. coli, however elevated counts of e. coli equate to a statistically raised risk of bad e. coli. In this case, caution is exercised.
It is still safe to fish in water with elevated levels of e. coli, as long as you wash your hands well and cook your food thoroughly.
Several factors contribute to an increase in e. coli rates including rainstorms, very warm days, windy days, certain types of contamination, or anything that stirs up the water.
Samples can be contaminated when drawn or during laboratory testing; or, calculation error can occur during data entry. To ensure a quality process, standardized procedures are in place to prevent sample contamination and eliminate calculation error; nonetheless, human error can be a possible cause for elevated test results.
Finally, all samples are sent to an independent, third party laboratory. Elevated test results trigger a two-pronged approach:
Signs are posted and e mail notices sent to alert residents and users; and,
Secondary samples are sent to a different independent laboratory, for ‘fast track’ 24-hour turnaround.
Second test results can trigger differing actions:
Results within the acceptable range cause the removal of signs, alerting an all clear.
Confirmed elevated count initiates a process to identify the source. Lee’s Summit and Missouri Department of Natural Resources (DNR) are notified.
The results for Prairie Lee Lake for the week of April 13, 2015 are 1,810cfu/100mL.