City of Plymouth water is tested weekly by an independent, state-certified laboratory and the results are submitted to the Minnesota Department of Health. Public water supplies are regularly tested for more than 100 contaminants that can cause health concerns, such as bacteria, nitrate, pesticides, solvents and metals.

Water plant operators also test water multiple times per day for appropriate chemical levels and water quality.

PFAS Testing by the Minnesota Department of Health

The Minnesota Department of Health has begun testing community water systems for per- and polyfluoroalkyl substances (PFAS), a family of manmade chemicals that have been widely used for decades. PFAS have been found in groundwater and surface water in Minnesota.

For more information about PFAS, and to view an interactive dashboard that details the status and results of testing for PFAS in Plymouth and other communities, visit the Minnesota Department of Health website.

The City of Plymouth works everyday to provide safe, quality drinking water and high quality service to residents and businesses. Before distribution, the city treats water by disinfecting it and improves the quality by removing iron and manganese, minerals that can affect the taste and cause staining.

City of Plymouth Water Treatment Process
	Water Source The City of Plymouth uses 17 wells, ranging from 302 to 473 feet deep to draw drinking water from groundwater sources – Prairie Du Chien-Jordan, Prairie Du Chien Group and Jordan aquifers.
	Step 1: Remove Iron and Manganese  Sodium permanganate is used remove iron and manganese from the water.
	Step 2: Filter Water is run through filter cells containing sand media to filter out iron and manganese particles, which attach to the sand in the filters.
	Step 3: Prevent Pipe Corrosion Zinc orthophosphate is used to prevent corrosion of pipes.
	Step 4: Improve Dental Health Fluoride is added to improve dental health, per Minnesota Department of Health mandate.
	Step 5: Disinfect and Kill Bacteria Water is treated with sodium hypochlorite to disinfect and kill bacteria and other microbes that can cause illness.
	Drinking Water Plymouth has two treatment plants that use the same process to treat water. Treated water is fed into Plymouth’s water distribution system, which consists of five water towers and one underground reservoir. Water towers may hold water from both treatment facilities, depending on demand.

What is the hardness of Plymouth's water?

• About 24 grains per gallon

How often is Plymouth's water tested?

• City of Plymouth water is tested weekly by an independent, state-certified laboratory and the results are submitted to the Minnesota Department of Health. Public water supplies are regularly tested for more than 100 contaminants that can cause health concerns, such as bacteria, nitrate, pesticides, solvents and metals. Plant operators also test water multiple times per day for appropriate chemical levels and water quality.

Where does Plymouth's water come from?

• The City of Plymouth provides drinking water to its residents from two groundwater sources – Prairie Du Chien-Jordan and Prairie Du Chien Group aquifers. The city uses 17 wells, ranging from 302 to 473 feet deep to draw the water. 

Where is my water treated?

• Both of Plymouth’s water treatment plants use the same process to treat water. Water from the treatment plants is fed into Plymouth’s water distribution system, which consists of five water towers and one underground reservoir. Water towers may hold water from both treatment facilities, depending on the demand.

What is the pH of Plymouth's water?

• Between 7.2 and 7.5 when it comes out of the ground