When the mercury rises in midsummer, water quality in the Chesapeake Bay — as well as its streams and rivers — matters as much to people as it does to fish, crabs and oysters.
And this year, many people might be exploring watering holes across the region for the first time as the coronavirus limits access to swimming pools.
But government agencies and watershed groups are working to remind residents that swimming in a natural water body is not the same as diving into a chlorine-treated pool. In Northern Virginia, for example, Fairfax County authorities sent out an alert in late June retelling residents that swimming in the county’s 1,600 miles of streams is still “highly discouraged.”
“It is important to remember that swimming in streams and stormwater can be dangerous and hazardous to your health,” the message stated. “These natural waters are continuously changing and can be susceptible to pollution that can cause health risks to people and their pets.”
The risks vary widely between locations and even at the same location on different days, as pollution is driven by the types of potential contamination sources nearby, the amount of recent rainfall and even the amount of current in the water.
“Just because there’s public access to a river doesn’t necessarily mean it’s a safe place to go swimming or wading,” Upper Potomac Riverkeeper Brent Walls said.
A frequent concern is enterococci or E.coli bacteria, fecal organisms that indicate the presence of potentially harmful bacteria. These bacteria are present in higher numbers after a rainfall, which can flush animal waste and raw sewage into the water.
In sufficient numbers, these bacteria can cause gastrointestinal illnesses, skin and ear infections, and some conditions that can be life-threatening. They can enter the human body through the nose, ears or other openings as well as through small cuts.
Other naturally occurring toxins and bacteria, such as Vibrio vulnificus, also enter the body through cuts and openings. But their presence is not necessarily linked to rainfall and can be difficult to predict, though some are more likely to occur in the summer. The diseases they cause grab headlines when they lead to death or the loss of limb but are quite rare.
The number of people sickened by water contact in the Bay region is unclear because tracking at the state and county levels varies widely. State departments of health track the number of sicknesses from Vibrio, for example, and report them to the national Centers for Disease Control and Prevention. The latest numbers from Virginia indicate that about 40 people there contract the disease each year.
Virginia also has a harmful algal bloom hotline (1-888-238-6154) that the public can use to report symptoms after potential contact with a bloom, which can include rashes, an upset stomach, diarrhea and vomiting. Dogs can have symptoms from ingesting bloom-tainted waters, too, including staggering, drooling, difficulty breathing and seizures. The state can investigate whether a bloom is harmful and could close public swimming areas in response.
But often — because water quality is quite literally a moving target — it can be too difficult to determine what caused an illness and whether the contaminant is still lingering in the water in real time.
So far, researchers say there is very little risk of contracting COVID-19 through water contact. (See Ready for a splash, but what’s in the water?).
Does your chosen spot for water play contain bacteria or pathogens that could make you sick? The answer depends on many factors. To find out, you may have to navigate a sporadic patchwork of testing and public reports.
“Even when water is tested, it can be difficult to answer the question, ‘Is it safe to swim?’ or ‘Am I gonna get sick?’” said Gabrielle Parent-Doliner, director of swimmable water programs at Swim Drink Fish.
The Canadian nonprofit runs Swim Guide, a website and phone app that aggregates recreational water quality data for the public from 8,000 sites in nearly a dozen countries, including a growing number of locations in the Chesapeake Bay watershed.
But the testing reported through Swim Guide is not consistent across popular recreation areas or by the same entities in each state. A local government might test a bayside beach every week, while a popular watering hole in a rural area may not be tested at all.
Chesapeake Bay advocates say they are often asked whether it’s safe to get on or in the water. But distilling water conditions and the latest data — which are rarely available in real-time — to a simple yes or no answer isn’t always easy.
Advocates also don’t want to frighten the public away from the water, because people who recreate in streams, rivers and the Bay often become champions for water quality.
“It’s a message we struggle with,” said Choptank Riverkeeper Matt Pluta, echoing a sentiment shared by many of the region’s waterkeepers. “We want to provide this information, but we don’t want to scare people.”
There are plenty of occasions when the waterways Pluta monitors on Maryland’s Eastern Shore are swimmable. “But it’s not all the time,” he said, “and that’s what we need to address.”
In 2018, Pluta started organizing an annual swim across the Choptank River as a tribute to clean water, complete with water-quality monitoring to ensure safety. But — between high bacteria levels one year and a coronavirus-related closure this year — the swim has only taken place one of the past three years. In 2018, a record-breaking rain the week before the late-May event washed farm fertilizer and other pollutants off the surrounding landscape and into the river, rendering it unsafe for a swim.
Expecting climate change to contribute to heavier rainfalls in coming years, Pluta said he’d consider it a win if the event actually takes place every other year.
“A good sign was that people were reaching out to me the week leading up asking if it was safe enough for them to swim. They were making that connection that lots of rain meant polluted water,” Pluta said.
Now that people are taking weekly swims in the river with a monitoring program in place, he said, “People are constantly asking me, ‘How much rain did we get last night? Is it safe to swim?’”
Not everyone makes that correlation, though. Pluta is dismayed when he sees families splashing at the water’s edge after a recent rain. And he still hears from locals who think the water might be cleaner right after heavy rain, mistakenly assuming that pollutants or bacteria would be diluted with relatively clean precipitation.
In Virginia, the Department of Health monitors water quality at 46 coastal beaches in the state, but most of the inland monitoring is done by riverkeepers or other groups, if at all. Still, Margaret Smigo, the department’s water-borne hazards program coordinator, is frequently asked whether local waters are safe for recreation. She often answers that question with one of her own: “Safe for whom?”
“There are people who have compromised [immune systems], so any natural water body might not be safe for them,” she said.
Signage at many water access areas warns the public to stay out of the water 48–72 hours after rainfall.
Public health and water quality experts say there are good reasons for this. For one, bacteria levels typically remain high for about that long after rain has carried pollutants into the water.
Another reason is, in areas where bacterial testing takes place, it can take about 48–72 hours to culture the bacteria in a lab and provide needed warnings to would-be swimmers. In the future, those tests could inch closer to real-time, but for now, many tests can only reveal weekly, biweekly or historical conditions.
If it rains between the time a test was taken and a sunny weekend, most groups now add additional warnings that the water quality has likely worsened since their last sampling.
Urban waters in flux
For several older cities in the Chesapeake Bay watershed, the advice to stay out of the water after it rains is more strongly worded. That’s because, in addition to other water quality problems, places like the District of Columbia, Baltimore, Alexandria, Richmond and Harrisburg still have raw sewage overflowing or leaking into local waters during heavy rain. (See Costs clog efforts to prevent sewage overflows, p. 24.)
Most of the larger cities that have sewage overflow problems have begun the costly process of correcting them. Local governments and riverkeepers tend to base their goals for when a river will be swimmable on the timeline for those improvements.
In the Anacostia and Potomac rivers around the District, work is under way to make the waterways swimmable by 2025, but pollution is still a challenge. A decades-old ban on swimming remains, even as local water testing shows that the rivers would be clean enough for a swim on some days.
“People are hearing stuff on public radio and thinking about swimming in the Potomac after all these years of people saying, ‘OMG, I’m not getting in that water,’” Potomac Riverkeeper Dean Naujoks said.
Naujoks said he still wants the public to maintain a level of concern about water contact. Several portions of the river his group monitors were swimmable for most of the summer in 2019, but that was not the case during a rainy 2018.
Not all urban waters have good news to report, though. And the look of the water won’t tell the full story.
Olivia Anderson, project coordinator for Anacostia Riverkeeper, said their team has seen more kids and families splashing around in the District’s sprawling Rock Creek Park this summer. While the District is working to fix leaky sewage pipes that run near or under the creek and its tributaries, the leaks still regularly occur, resulting in high bacteria levels that could make people sick.
“They have this lovely water that people walk by, and some people don’t know that Rock Creek frequently tracks the highest with a lot of bacteria,” Anderson said.
“When we give boat tours, I expressly tell people, ‘Do not let your kids go swimming in Rock Creek Park,’ ” said Robbie O’Donnell, the watershed program manager for Anacostia Riverkeeper. “That area where we monitor at Melvin Hazen Run — it looks like a pristine creek and it’s one of the dirtiest water bodies we monitor.”
Anacostia Riverkeeper Trey Sherard said those portions of Rock Creek are the only waters in eight years of river-keeping that have ever made him sick. Sherard said he had eaten lunch a couple hours after fetching a stray whiffle ball out of the water near Pierce Mill Dam; his hands weren’t even wet anymore.
“I was miserable for 24 hours,” he said of the gastrointestinal symptoms he connected to the water contact that day. “It’s the sickest I’ve ever been, stomachwise.”
The Anacostia Riverkeeper group is in its third year of consistently monitoring water quality at several sites in Rock Creek and the Anacostia, in part to track progress toward safe swimming. The results are posted to Swim Guide, where the District pages remind readers that it is still illegal to swim in those waters, though many people come in contact with the water through wading or other activities. This year, the monitoring is being expanded to several Maryland tributaries to the Anacostia as well.
Anderson said it’s difficult for river advocates to keep people engaged with their local waterways but also warn them about risks from water contact.
“There’s a fine line of sharing the good news that’s happening but also cautioning people to restrain themselves,” she said. “We do want to share that the river is making strides, but we’re not there yet.”
Baltimore Harbor Keeper Alice Volpitta juggles a similar message. Every year, she said, someone jumps in the Baltimore Harbor for a swim despite its reputation for pollution. Advocates for local water quality had been working toward a 2020 goal for making Baltimore’s waters swimmable, but sewage still routinely leaks into local waters.
“One day [bacteria levels] can be well below the [safety] threshold, and the next day it’s 20 times the threshold,” Volpitta said. “With our leaky infrastructure, you can’t predict which day will be safe. We need to focus on fixing the problem before we get ahead of ourselves about what’s to come.”
Rural waters still at risk
Figuring out whether a waterway is safe for swimming, wading or paddling can be even harder in rural areas where there is little to no monitoring and a perception that less populated areas are more likely to be clean.
And suburban swimmers accustomed to bayside beaches — which are more likely to be monitored for bacteria by state or county officials — might be surprised to find that a popular rural watering hole near a state park often doesn’t get the same level of oversight.
Shenandoah Riverkeeper Mark Frondorf said the correlation between recent rain and unsafe water quality still holds true in areas where fertilizer, animal waste or leaky septic systems could be contributing bacteria to the water.
“If the water looks chocolate and muddy, chances are there will be other pollutants in there,” Frondorf said. “I encourage people to trust their spidey senses. If it looks bad, don’t go in it.”
That’s an oversimplification, he admits, but it’s not a bad place to start. People who plan to go tubing on the Shenandoah or the South Branch of the Potomac might want to postpone the trip for a few days if heavy rain occurs along the float route or in upstream areas.
The Friends of the Shenandoah River conducts water quality monitoring for bacteria. Though the testing isn’t frequent enough to be a deciding factor on a given day, the historical results posted to Swim Guide provide a sense of how often an area is safe for water contact.
Upper Potomac Riverkeeper Brent Walls suggests avoiding water contact near cow pastures, especially in slow-flowing areas. And if the water is green, scummy or smelly from algae, steer clear. While not all algal blooms are harmful, blue-green algae and red tides are among those that can make humans sick.
Walls is extra cautious about where children jump in, because they are more likely to ingest water while splashing around.
Some of the easiest places to access the water — such as boat ramps where fuel, trash and stagnant water are also present — could be the worst places to go for a swim, he said.
Ted Evgeniadis, the Lower Susquehanna Riverkeeper in Pennsylvania, wades in the river wearing a pair of shorts all summer fly fishing for smallmouth bass. But after a good rain, you will find him at home, or at least wearing chest waders.
He’s not willing to take a chance that bacteria from sewage overflows, fertilizer runoff from farm fields, or even oils and fluids from roads, will get in a cut and make him sick.
Pennsylvania’s streams and rivers are tested periodically to see if they are safe for recreation. But not day to day, or even week to week.
Evgeniadis recommends checking the state’s designation of a stream. Is it a coldwater or warmwater fishery? Coldwater streams tend to have higher water quality. If the water supports aquatic life, is rated exceptional value or high quality, the need for caution is low. Most streams in Pennsylvania and their categories may be found on an interactive online map maintained by the state Department of Environmental Protection. To find it, search for the latest Pennsylvania Integrated Water Quality Report in your browser.
Seek info, take precautions
There are several sources to check for information about water quality. A good place to start is the Swim Guide app and website, which a growing number of groups use to share monitoring data about beaches and swimming holes.
You can also search the web for the name of state-run beaches combined with the phrase “water quality.” It will likely lead you to a website where recent monitoring results are posted, often by the state or local health department.
Also, try to find out if a nonprofit group exists for the stream or river you want to visit. They may monitor water quality and offer data to help you decide when and where to take a dip.
Kellogg Schwab, a professor of water and public health at the John Hopkins University and director of the university’s Water Institute, said people assessing their level of risk before entering a natural water body should start by talking to their physician. If they’re healthy, there are still other precautions that can help them recreate safely.
Chief among them, Schwab said, is avoiding the water after rain, but he also recommends keeping your head above the water when possible and having children wear ear and nose plugs. And water shoes are a good idea for all. Yes, he said, recreating in natural waters comes with some risks, but — as someone who studies food– and waterborne diseases — so do a lot of other daily activities.
“When it rains, you need to wait and let that clear out,” he said. “But the Bay is a wonderful ecosystem that recharges itself and purges. The more we protect our small streams, the better it will be.”