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PFAS in Groundwater

Temporary Treatment Facility June 2020June 18 Update: Temporary water treatment plant now in service

The City of Woodbury’s new temporary water treatment plant is now operational. The facility, located near the intersection of Valley Creek Road and Tower Drive, is treating water from four wells to meet water quality standards and guidelines for per- and polyfluoroalkyl substances (PFAS). 

Seven of the city’s 19 wells were removed from service since 2017 due to PFAS levels that were above federal and state water quality standards and guidelines.

Bringing four of the seven wells back into service allows the city to meet the increased demand for water during the summer months. The remaining three wells will remain out of service at this time.

The temporary water treatment plant, which typically takes about 18 months to two years to construct, was completed in about five months. In order to meet peak summer demand, it was critical the temporary treatment facility was operational as quickly as possible. The City would not be operating the facility today without the work and cooperation of the State of Minnesota, 3M, the City Council, numerous city staff, our engineering consultant teams, and the construction expertise of the project contractor.

Construction on the site will continue through the summer to finalize building components and site restoration.

Water efficiency remains critical
With the temporary water treatment facility now operational, the potential for increased irrigation restrictions this summer is significantly reduced. Thank you to all residents who made an effort to reduce their water use to eliminate the need for additional water restrictions while construction of the facility took place.

However, it is important to remember the city’s lawn watering policy remains in effect. The watering rules allow lawn sprinkling on an odd/even schedule (only before noon and after 5 p.m.).

Remember, just because the city allows watering on an odd-even schedule doesn’t mean residents and businesses need to water that often. To keep your lawn green, it only needs 1 inch of water per week, including rainfall. 

Tips on smart water use

Smart irrigation controllers available at a reduced rate
When irrigation is necessary, make sure you are using the most efficient technology available. WaterSense certified smart irrigation controllers are now available to homeowners at a discounted rate of $35. These controllers connect your irrigation system to local weather forecasts through your WiFi to adjust the system before and after a rain event, and also corrects for temperatures and wind speeds. Since the city started this program in 2016, these controllers reduced water use by an average of 30,000 gallons of water per household per year (resulting in smaller water bills, too).

All irrigation controllers installed in the city in 2018 and after are required to be WaterSense certified. 

Learn more and purchase a smart irrigation controller

Long-term water treatment solutions
The temporary water treatment facility is expected to be in operation until a long-term water treatment solution can be implemented in the next five to seven years. Funds for the long-term solution are expected to be available from the $720 million settlement the state received from 3M in 2018. The State of Minnesota continues to study long-term treatment options for several communities in the east metro area and is expected to share its recommendations with the cities this fall.

About PFAS
The 3M Company made PFAS at its Cottage Grove facility from the late 1940s until 2002. PFAS wastes were disposed of at multiple sites in Washington County. The source of the PFAS in Woodbury’s groundwater has been identified as these disposal sites.

Funding for the Woodbury temporary water treatment plant is provided through the 2018 settlement agreement between the State of Minnesota and 3M. This arrangement includes a $40 million provision for temporary facilities meeting the requirements of the 2007 settlement agreement between the same two parties.

If you have questions about the city’s water system and the impact of PFAS, contact Public Works at 651-714-3720 or

PFAS Resources

Learn more about PFAS in groundwater

PFAS Monitoring Results in Woodbury's municipal wells

MDH Well Health Risk Advisory Map

Remediation Activities
In 2011, the Minnesota Pollution Control Agency (MPCA) completed remediation activities at these sites to reduce the amount of pollutants released from these sites in the future.

3M, under direction from the MPCA, continues active site remediation. For the Woodbury site, remaining contamination is captured by pumping approximately 1.25 billion gallons of water annually to a treatment plant and discharging it to the Mississippi River.

Visit the MPCA website for more information about the remediation activities.

Private Water Supply Wells
As a result of the EPA’s new guidance and MDH updated HBV for PFOA and PFOS, MDH is sampling private wells within Washington County and will issue additional drinking water advisories as needed. Until their private wells are tested, residents who have concerns about their health can take steps to reduce their potential exposure to PFAS. Information on point-of-use filters and other steps people can take in their homes can be found on the MDH website.

Private water well owners or residents interested in treating the water after it reaches their home can learn about home treatment options at

Residents who have questions about their private water supply well and whether it is impacted by this change should contact MDH.

June 12 Update: Temporary treatment facility nears completion

April 13 Update: Increased water restrictions likely until temporary treatment facility is complete

March 4: MPCA and DNR listening and information sessions presentation

Feb. 21 Update: Seventh Woodbury well has PFAS levels above water quality limits

Jan. 8, 2020 Update: City begins work on temporary water treatment facility

Oct. 24 Update: Public Meeting held at Woodbury High School

Oct. 18, 2019 Update: Sixth Woodbury Well has PFAS levels above health risk limit

Aug. 28, 2019 Update: Expedited project awarded to and accepted by Woodbury

April 3, 2019 Update: Minnesota Department of Health issues new Health-Based Guidance Values

March 2, 2018 Update: $850 million settlement provides funding for cleaning up drinking water