Swim Guide Watershed Report: French Broad River
In the past year, the French Broad River Watershed experienced a range of highs and lows (we’re talking about bacteria counts, folks!). We’ll start with the good news, including which water testing sites had the lowest bacteria counts across the watershed. Then, we’ll give you the year’s bad news by spotlighting sites with the highest bacteria counts. We’ll conclude with achievable solutions for the future and a call to action so you can continue to help us protect the places we share.
Before we dive into our water quality summary, let’s review important terminology to help us better understand the data our Riverkeepers, volunteers, and Clean Waters teams worked so hard to collect, analyze, and report. Cfu, or colony forming unit, is a data metric scientists use to estimate the number of microbes present per 100 milliliters of a singular water sample. Microbes (also known as microorganisms) include bacteria, algae, and fungi. Like most things, some microbes are good for human health and some aren’t. We test for E. coli bacteria because it’s the best indicator for the presence of microbes that pose threats to human health.
According to the US Environmental Protection Agency (EPA), 235 cfu/100mL is the safe standard for primary recreational waters, where people are most likely to engage in recreational activities involving underwater immersion and potential water ingestion.
Good news headline: French Broad Whitewater Sites Experience Applaudable Improvement in 2021
The French Broad in Madison County was cleaner this summer than in past Swim Guide seasons. Whitewater sections at Stackhouse, Hot Springs, and Big Laurel were some of the best testing sites. These sites routinely passed the EPA’s 235 cfu/100mL safe standard, improving from 2020-2021. Another popular whitewater section — the Pigeon River in Hartford, Tennessee — was clean all summer, with most weeks showing an E. coli count of zero.
Most of our testing sites experienced slight improvement this year compared to 2020’s testing results. This is likely due to less rainfall during the Memorial Day to Labor Day sampling season.
Bad news headline: French Broad Besieged by E. coli as Bacteria Battle Babbles on
About Our Swim Guide Program
Swim Guide is an international program used by Riverkeepers and other advocates to provide up-to-date recreational E. coli data for beaches, lakes, and rivers worldwide. E. coli is a bacteria found in the fecal waste of warm-blooded animals, including humans, and indicates contamination in our waterways. E. coli levels increase with rainfall events due to surface runoff and sewer overflow events.
Samples are collected every Wednesday from Memorial Day to Labor Day. Volunteers collect surface water samples in a 100mL sample bottle and drop samples off at the lab, to be processed by MountainTrue staff. Results from samples are measured in MPN, the most probable number of colony-forming units (cfu). The EPA’s limit for recreational water quality is 235 cfu/100mL. The EPA estimates at that concentration, 8 in 1,000 people will contract an illness.
Pass/Fail results are updated every Friday on www.swimguide.org to inform the public about local water quality. We use the data generated from our Swim Guide Program to identify sites for follow-up sampling. We sample in both urban and rural areas. Determining the location and source of E. coli in our waterways is one way we can hold polluters accountable.
The French Broad’s long and sometimes stinky history with E. coli is no secret to watershed locals. Our riverkeepers, volunteers, and Clean Waters Teams kept keen (but not pink!) eyes out for harmful strains of this belligerent bacteria while conducting water quality tests at 40 sites across the French Broad River Watershed.
We added two new testing sites along the French Broad in Transylvania County at Lyons Mountain and Island Ford this year. Unfortunately, both sites’ water quality and bacteria count ranked among the worst. Our testing site in South Asheville’s Shiloh community secured the worst spot with a season average of 3393 cfu/100mL.
Hominy Creek in West Asheville remains an E. coli haven. Through separate DNA sampling, we’ve been able to identify cow and human waste as the top sources of E. coli in Hominy and Mud Creeks. At the same time, sewer overflows also negatively impact the latter. While Mud Creek at Brookside Camp Road experienced slight improvement from 2020 to 2021, it remains one of the worst sites we sample with an average E. coli count of 1535 cfu/100mL.
The week of July 28 proved to be the summer’s worst. Just 23% of the sites passed the EPA’s safe standard with 1283 cfu/100mL as the average value per site.
Future news headline: Staving off the French Broad’s Bacteria Pollution to Save Water Quality
While we saw a slight improvement this year, there’s much work that needs to be done to reduce bacterial pollution in the French Broad River. We’re advocating for additional funding for County Soil and Water Conservation Districts to help farmers implement additional best management practices, like keeping livestock out of waterways and installing stream buffers to mitigate harmful, bacteria-laden runoff. We believe these solutions will significantly improve water quality at Hominy Creek and other agricultural areas, engendering a free-flowing domino effect that will positively impact other French Broad River Watershed sections.
Moving forward, MountainTrue will:
- Continue to monitor sites of most concern while aiming to pinpoint and eliminate sources of E. coli pollution at our newest testing sites.
- Leverage our connections with city, county, and state officials while further developing valued relationships with community members to combat threats posed to water quality by animal agriculture, faulty wastewater infrastructure, and septic failures.
Want to learn more about our efforts to bring about clean water for all? Check out our ILoveRivers webpage and join MountainTrue’s dedicated community of volunteers to help us protect the places we share.