SWIM results after Tropical Storm Cristobal

As expected, heavy rain from Tropical Storm Cristobal led to elevated bacteria levels at many sampling sites on Wednesday. 8 of 11 sites tested by Mobile Baykeeper showed levels above the EPA’s threshold for safe swimming. Additionally, ADEM reported higher bacteria levels at numerous sites. See the map below for details.

Tropical Storm Cristobal overwhelmed old infrastructure causing numerous sewage spills in the area. Mobile Baykeeper advocates for investment in infrastructure to ensure healthy waterways and communities. Click here to see a map of the spills and read about what caused them. 

We are seeking sponsorships for additional SWIM sites so we can provide more information about safe swimming. We hope to add Mobile’s Milkhouse Creek and others when funding is available. If you want to help make this happen, please consider a sponsorship or become a member!Sponsor SWIM Testing at Milkhouse Creek!


SWIM Table


During a normal SWIM season, ADEM/ADPH (25 sites) and Mobile Baykeeper (12 sites) test weekly. Mobile Baykeeper is testing during the Covid-19 outbreak. ADEM/ADPH is currently evaluating their testing schedule and may make adjustments. 

At the 12 Mobile Baykeeper sites, except Fish River at Bohemian Park, we test for enterococci, a bacteria that best indicates fecal contamination in salty or brackish water. In Fish River at Bohemian Park, which is our only site with no tidal influence, we test for E. Coli. We base our SWIM evaluations on the EPA threshold for swimming advisories, which is 104 mpn/100 mL for enterococci and 235 mpn/100 mL for E. Coli.

Please remember to use caution in and around the water following heavy rain as sewage overflows and stormwater runoff may contain high levels of bacteria. In cases of high bacteria levels, avoid introducing open wounds to the water. If you see something of concern, please report it via the Water Rangers app

Our tests do not indicate the presence of Vibrio vulnificus, a flesh-eating bacteria that naturally occurs in warm, brackish waters. Our “safe” level refers to the level of Enterococci or E. coli, bacteria that indicate fecal contamination. Be advised that other threats may exist. Avoid entering the water with open wounds. For more information on BEACH testing and how the SWIM program works please visit our website.

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