With weekend temperatures climbing into the 90’s, many people may be tempted to cool off with a dip in the nearest river, but experts are warning that may not be safe after last week’s torrential rains in the central part of the state. Sandy Hausman spoke with officials in Richmond and Charlottesville, then filed this report.
As Bacteria Monitoring Manager at the Rivanna Conservation Alliance, Julia Ela spends a lot of time studying the river and the streams that flow into it. Today she surveys a wide, fast-moving section near downtown Charlottesville.
“I would say this is very high right now – very muddy,” she says.
But when she and about 30 volunteers did a monthly check of water quality after last week’s rain, they found more than mud. Bacteria levels were about ten times higher than normal.”
One reason for high bacteria levels in rivers around the state is that three old cities -- Richmond, Lynchburg and Alexandria -- have sewer systems that combine waste water and storm water into a single pipe leading to a treatment plant. James Beckley is with the Virginia Department of Environmental Quality.
“When you start having an inch or two inches of rain, the wastewater is not really designed to handle that kind of flow," he explains, "so when they’re not able to handle the water they’ll open up the gates, so a mixture of storm water and waste water that’s untreated goes into the river.”
In other places, Julia Ela adds, waste from farm animals, dogs and cats leads to high levels of e-coli.
“A lot of pet waste especially that builds up over the winter gets washed off in these spring rains. That causes a spike.”
And a fast-flowing river or stream is also more likely to be contaminated.
“E-coli does tend to like living in sediment at the bottom of the river," Ela says. "The sediment is nice and calm at the bottom. We don’t see high levels, but with all this churning and high water we might see a little bit more lingering, just because of all the turbulence.”
High levels of e-coli could persist for another week, and those readings are a sign that other kinds of bacteria could also be present. The bottom line – swimming might not be a good idea just yet, and Beckley says residents of the state’s capital should be especially cautious.
“Richmond is the only city that’s next to a class four rapid, so when water levels get too high, conditions become way too hazardous to swim or boat in.”
The good news, he adds, is that overall, long-term, Virginia’s rivers are getting cleaner.
“We’ve probably doubled or tripled our population in the last thirty years, Beckley says, "and despite that we are continually improving our environment – our water quality and air quality.”
For now he offers this advice.
“If it hasn’t rained within about 48 hours and the water looks clear, generally the bacteria numbers should be low.”
And if you do take a dip, try not to swallow river water, then take a shower or wash up afterward.
“When you get out of the water it’s good to wash your hands before you eat, even in a swimming pool it’s a good idea to do that, because even though they chlorinate, it doesn’t always mean the water is actually clean.”
Local health departments and the James River Association may also offer timely information about popular places to swim. I’m Sandy Hausman.