City of Woodbury releases plans to protect drinking water
A new study regulated by the state of Minnesota identifies various water wells in Woodbury as highly vulnerable to contamination.
Part one of the “Wellhead Protection Plan” released by the city of Woodbury last week, assessed all 18 wells, including three that were put in after the plan was last updated in 2004.
All wells in Woodbury pump from the Jordan Sandstone aquifer. The city is in the process of finalizing a permit for the 18th well.
The updated study is split up into two parts, with the first identifying the delineation of wellhead protection areas and drinking water supply, and assessesing vulnerability to contamination, said John Greer of PG Barr Engineering, the firm working with the city on the study.
Vulnerable wells are at risk for contamination but how soon contaminants will reach the Jordan aquifer could take years, Greer explained.
“It could take decades, maybe a century,” he said.
Various parts of the city wells – mostly clustered into the Tamarack well field area with others on the east side of the city – were identified as highly vulnerable, according to the study.
“Because of the difference in geology, you have different vulnerability in the aquifer,” Greer said.
According to a city report, potential sources of contaminants can include abandoned wells, poorly maintained septic systems, improper disposal of household hazardous waste, overuse of fertilizers, leaking storage tanks, unreported spills, illegal dumping and contaminated stormwater runoff.
The second part of the Wellhead Protection Plan will identify goals and objectives, a plan of action and evaluation of those potential sources of contamination.
The city is expected to begin work on the second part this spring and complete it by the end of the year or early 2015.
Environmental source specialist Jim Westerman said the city is looking at modifying setback ordinances to make sure potential sources of contamination are not placed within a certain number of feet from wells.
The city held a public information meeting on the plan on Jan. 14 where a handful of residents attended.
One raised a question regarding perfluorochemicals (PFCs) and whether the plan identified that as a contaminant to the city’s wells.
“We didn’t see anything that indicated we needed to worry,” Greer said.
PFC levels found in the wells didn’t exceed Minnesota Department of Health guidelines for safe drinking water. “PFCs are out there, there is no hiding that,” Westerman said, but not at dangerously high levels.