By Nicole Eastman, Riverkeeper Assistant
This week Yadkin Riverkeeper finished its 15th and final week of E. coli testing for Swim Guide! Thank you to all our amazing volunteers who collected water samples from swim and paddle accesses from the mountains in Happy Valley to High Rock Lake every Wednesday. A special thank you to our Swim Guide sponsors, Cube Hydro Carolinas and Bill Jenkins & Pam Townsend.
From May 21 to August 27, 2025:
YRK and volunteers collected 378 samples over 15 weeks
YRK’s facebook posts reached 110,501 people
YRK’s instagram posts had 4,678 views
7 Swim Guide Sites were sponsored
Swim Guide provides the public important information about the water quality of their local waterways. Yadkin Riverkeeper tests along the Yadkin River, W. Kerr Scott Lake, and High Rock Lake at 26 different locations. The EPA guideline that YRK currently uses to determine whether a site is safe for recreational use considers water with more than 235 colony-forming units (CFU) of E. coli per 100 mL as failing to meet water quality standards. However, the EPA has since updated its criteria, setting a threshold of 126 CFU/100 mL for primary contact recreation, such as swimming, and 886 CFU/100 mL for secondary contact activities such as boating, fishing, and paddling. While YRK used the previously recommended 235 CFU guideline this summer, we will explore the updated two-threshold system to determine if the new limits set by EPA better reflect when the sites are safe for swimming and when they are safe for other recreational activities.
Of the 378 samples tested, 213 met the E. coli guideline, a 56.3% passing rate which is a 10 point decrease from last year. In addition to determining the weekly conditions of a river or lake site, YRK is able to identify bacteria “hotspots” for high E. coli within the watershed. This year, Ronda failed the greatest percentage of time, 93%. YRK is investigating the causes for a substantial failing rate and will do additional testing to determine if land application sites nearby are causing this severe contamination.
Additional hotspots include Roaring River and Crater Park with a failure rate of 86.6%, Yadkin Shore with a failure rate of 73.3%, and Marley’s Ford with a failure rate of 66.6%. The YRK staff is digging deeper into the potential sources of pollution that may be impacting the E. coli levels at these locations and Abbott’s Creek which has experienced high bacteria levels the latter part of the season.
Sites along the two lakes, Kerr Scott and High Rock, passed the most frequently including Boomer, Flat Swamp, and Pebble Beach.
If you have any questions about the Swim Guide program and the results this summer, please reach out to Nicole at nicole@yadkinriverkeeper.org.