By Nicole Eastman, Yadkin Riverkeeper
Photo taken by Walt Unks, The Winston-Salem Journal at the Shallowford access
Earlier this month, Yadkin Riverkeeper finished its final week of E. coli testing for Swim Guide! Our summer intern, Lance Morrison, did a great job coordinating the program this summer. 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 Friends of Big Elkin Creek.
From May 21 to September 2, 2026:
YRK and volunteers collected 392 samples over 16 weeks
YRK’s facebook posts reached 59,597 people
18 volunteers collected samples over the course of the summer
5 Swim Guide Sites were sponsored
1 news article written about this important program in the Winston-Salem Journal
Swim Guide provides the public important information about the water quality of their local waterways. Yadkin Riverkeeper tests along the Yadkin River, the South 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, some regional DEQ offices use different 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 guidelines better reflect when the sites are safe for swimming and when they are safe for other recreational activities.
Of the 392 samples tested, 281 met the E. coli guideline, a 71.7% passing rate which is a 15.4 point increase from last year. The passing rate increase is most likely due to the drought we experienced this summer and the decrease in precipitation and runoff into the river. 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, Ferguson failed most frequently with an extremely passing rate of 8% or 1 week out of 13 sampled at this site. YRK is investigating the causes for a substantial failing rate and will do additional testing to determine if cattle farms upstream are the main contributors of fecal contamination.
Smoot Park was another hotspot this summer with a passing rate of 37.5% (6 out of 16 weeks). This may have been a result of lower water levels in the river which receives wastewater from utilities upstream and runoff from North Wilkesboro.
Sites along the two lakes passed the most frequently with the three sites on Kerr Scott, Boomer, Berry Mountain, and Fort Hamby, passing 100% of the time.
If you have any questions about the Swim Guide program and the results this summer, please reach out to Nicole at nicole@yadkinriverkeeper.org.