During the month of August, people may notice new signs at local municipal beaches.
The Northwestern Health Unit is installing permanent metal signs at beaches to inform the public that heavy rainfall and/or strong winds can cause a spike in the level of bacteria in the water for a few days following the weather event.
Dr. James Arthurs, medical officer of health for the health unit, has directed that the signs be installed.
“We have an obligation to let the public know that swimming at a beach may not be a wise option after a heavy rain storm, especially when we have not yet received verification that bacteria levels are within the safety standards set by the province,” Dr. Arthurs said.
It takes three days for the results of weekly beach water sampling to be available to the Northwestern Health Unit from the public health lab in Thunder Bay.
Ironically, it is during this time lag between sampling and results that the health risks of swimming after a storm are greatest.
“We believe that posting permanent public awareness signs will help address this issue,” Dr. Arthurs explained.
Historical data of beach sampling across the province show that weather conditions are the leading cause of poor water quality.
Heavy rains and/or strong winds which occur within the 48-hour period before weekly beach sampling routinely show an increased level of E. coli bacteria in the water.
Exposure to high levels of E. coli can pose some potentially serious risks to bathers, including a variety of skin, eye, nose, and throat infections, as well as gastrointestinal illness.
Children, babies, the elderly, and people with pre-existing health conditions are especially vulnerable.
“We can’t predict a summer like the one we are having this year,” noted Jennifer McKibbon, enforcement manager for the health unit.
“Normally we might expect two or three storms of the magnitude we have seen all summer long.
“Everybody wants to enjoy nice days at the beach, and beach water is safe to swim in most of the time, but we believe it is important to give the public information that can help them make an informed decision about whether to swim after a storm,” she added.
The Northwestern Health Unit advises the public to evaluate current weather conditions, and those of the past 48 hours, before going swimming.
Calm and clear water generally is associated with lower bacteria levels, whereas heavy rainfall and strong winds can cause cloudy water and higher levels of bacteria.
The Northwestern Health Unit will continue to sample all municipal beaches on a weekly basis throughout the bathing season, and still will act to close beaches with appropriate signage for adverse events such as chemical, physical, or extreme microbiological hazards.