December 1, 2009

E. coli found in Mill Creek
Local groups plan actions

By Adam Lapierre
for The Chronicle

     As part of its water quality monitoring program, Columbia Riverkeeper tests local waterways on a monthly basis for contaminants. Trained volunteers take samples from creeks and rivers around the gorge, which are then analyzed to determine what levels of certain contaminants are in the water.
     Recent tests on Mill Creek in The Dalles and Phelps, Whiskey and Indian creeks in Hood River showed high levels of E coli, an indicator of fecal contamination. Levels in all four creeks through the summer exceeded Oregon’s health safety standards by several hundred percent, with Mill Creek’s 10th Street testing site at 415 percent above the Oregon Department of Environmental Quality’s 126mpm safety standard.
     A small level of fecal contamination is not uncommon, but such high levels point to human-related causes upstream of the test site.
     “Potential sources of fecal contamination in creeks include broken sewer pipes, failing or unmaintained septic tanks, and direct discharge of waste from livestock and wildlife,” Riverkeeper officials noted in a press release. “Other sources include contaminated stormwater, and agricultural and residential
fertilizers. High levels of organic matter such as plant material may also encourage pathogenic bacteria.”
     With seasonal rains increasing water levels in the creeks, fecal levels will likely test much lower in the coming months, but, as Riverkeeper notes, that is no reason to let the issue go unchecked.
     As a result of the data submitted by Riverkeeper, Mill, Phelps, Whiskey, and Indian creeks will be added to Oregon’s list of impaired water bodies, which will require Oregon DEQ to investigate potential sources of fecal contamination and design a plan to restore water quality.
     “We can wait for ODEQ to take care of the problem, or we can be proactive as a community and ensure our septic systems are up to date and that potential fecal sources are kept at least 100 horizontal feet away from water bodies,” said Rachael Pecore, water quality scientist with Columbia Riverkeeper. “Don’t wait for a knock on your door; double-check whether you’re on city sewer or septic and call your county health department if you don’t know when your septic system was last pumped.”
     Pecore noted that septic systems should be emptied every three to five years.
Although, if left unchecked, fecal contamination can reduce oxygen levels critical to fish and other aquatic life, the highest risk of such contamination is to human health.
     “Levels above state safety standards indicate the potential for harm by pathogens associated with feces such as cryptosporidium, giardia, ear infections, viral and bacterial gastroenteritis, and hepatitis A,” Riverkeeper noted. “Fecal-infested waters pose the greatest threat for children, the elderly and those with weakened immune systems. In general, swimmers with open cuts or wounds are advised to avoid rivers, wash off afterward, and contact their doctor if infections or symptoms arise.”
     “The sources of fecal contamination in Mill Creek remains a mystery, but at least The Dalles Watershed Council now has a year’s worth of data so that we can begin to track the problem,” said Kate Merrick, the Dalles Watershed Council Coordinator. “With additional testing and the help of the local community we hope to identify the source and remedy the problem as quickly as possible.”