West BloomfieldJuly 24, 2014
Scotch Lake beach monitored for E. coli
By Cari DeLamielleure-Scott
C & G Staff Writer
WEST BLOOMFIELD — Following a two-week closure due to E. coli contamination, Scotch Lake Residents Beach will be monitored weekly by the Oakland County Health Division.
Samples were collected at the beach as part of the Oakland County Health Division’s Beach Monitoring Program, and the results of the sampling exceeded the allowable limits set by the state for E. coli, which is 300 E. coli per 100 milliliters. Scotch Lake was closed July 2-18.
The Beach Monitoring Program is a long-standing program in which Health Division staff members sample swimming beaches in the county. Oakland County has approximately 300 beaches on 100 lakes, according to Mark Hansell, chief of environmental special programs with the Health Division. The Health Division takes samples, at a minimum, from all public beaches each year, which is only about 45 beaches out of the total, and when resources are available, staff samples the remaining “semi-public” beaches, or neighborhood association beaches, Hansell added. This year, the Health Division will sample 73 beaches on 55 lakes in the county.
Because of the number of beaches, the Health Division rotates the semi-public beach samplings, and it takes four to five years to complete, he said. Prior to the 2014 sampling of Scotch Lake, the beach was tested in 2008 and 2003, and was closed July 8, 2008, and July 21-Aug. 5 the same year due to high bacteria levels, according to the Michigan BeachGuard System, which displays closures, advisories, sample results and monitoring of beaches in Michigan.
The Michigan BeachGuard System shows that the daily mean of Scotch Lake Residents Beach was at 395 E. coli per 100 milliliters July 2 and got as high as 758 E. coli per 100 milliliters July 10.
The geometric mean, Hansell said, controls the “really highs” and the “really lows” in order to have a clearer picture of water quality.
“Oddly enough, we were concerned about the number of days … that the (beach had) been closed, and we have initiated a more intense investigation about what may be contributing to this lake,” Hansell said. BeachGuard states that the source for the E. coli this year was stormwater runoff.
Hansell said that because this is not a public beach, sometimes “the care is a little less than what you would get at a truly public beach.” He added that staff members noted significant lake vegetation in their sampling.
The E. coli levels decreased on their own, which Hansell said is normal because water has the ability to clean itself, and the results taken at the swimming area were not indicative of the overall quality of the lake.
E. coli can cause symptoms of illness, but not all E. coli will cause symptoms, according to Anne Chen, section head of infectious diseases at Henry Ford West Bloomfield Hospital. Most E. coli strains are actually part of the human intestinal flora, she said, but some strains, especially when acquired from a person’s surroundings, can be harmful.
Chen said that the reason health authorities monitor for E. coli is that the bacteria is an indicator that there is “probably another disease-causing bacteria in the water, as well.”
“Different parts of the water have different levels of bacteria. … If there is a high level of bacteria now, why would it be safe in a couple of days? The answer is that the E. coli bacteria doesn’t survive long in the water,” Chen said, adding that within 48 hours, the E. coli levels will be reduced through natural mechanisms, like the wind and sun exposure.
Because E. coli is a normal part of the human intestine, E. coli is difficult to check for in people, she said. However, there are some harmful strains that can be tested for, like through stool sampling, that may cause abdominal pain and diarrhea.
“If someone is experiencing persistent abdominal cramping and diarrhea, they should seek help from a medical professional and be evaluated,” Chen said.
Because the Oakland County Health Division cannot sample every semi-public beach in the county each year, the Health Division encourages residents to personally monitor their beaches by requesting a beach sampling kit. The kit, which costs $6, includes three bottles and instructions for the resident to take a sample. The Health Division will conduct the analysis.
To review beaches sampled in Michigan, visit www.michigan.gov/deq and search “BeachGuard System.” The Oakland County Health Division also posts county sampling results daily at www.oakgov.com. Both websites detail this year’s closures.
For more information about the Oakland County Health Division or for questions regarding Scotch Lake Residents Beach, call (248) 858-1312.