How hard is the water in St. Louis Park, MN?

Tap water hardness
112mg/L
6.5gpg
Moderately hard

Reported by Saint Louis Park · March 2025

MN typical
160 mg/L
EPA health violations since 2016
0
Softener for 3 people
24k grain
Data
Utility report

Tap water in St. Louis Park has about 112 mg/L of hardness, which is 6.5 grains per gallon. On the USGS scale that counts as moderately hard. The number comes from Saint Louis Park, dated March 2025.

St. Louis Park on the hardness scale, with nearby cities
060120180240300360+MN typical 160Brooklyn Center: 79 mg/LBrooklyn Center 79Minneapolis: 89 mg/LMinneapolis 89Golden Valley: 90 mg/LGolden Valley 90Eden Prairie: 99 mg/LEden Prairie 99Bloomington: 100 mg/LBloomington 100Edina: 146 mg/LEdina 146Hopkins: 163 mg/LHopkins 163Minnetonka: 186 mg/LMinnetonka 186Robbinsdale: 201 mg/LRobbinsdale 201St. Anthony: 254 mg/LSt. Anthony 254St. Louis Park 112mg/L as calcium carbonate060120180240300360+MN 160Minneapolis: 89 mg/LMinneapolis 89Golden Valley: 90 mg/LGolden Val. 90Edina: 146 mg/LEdina 146Hopkins: 163 mg/LHopkins 163Minnetonka: 186 mg/LMinnetonka 186Robbinsdale: 201 mg/LRobbinsdale 201112 mg/Lmg/L as calcium carbonate
Soft 0–60 mg/LModerately hard 61–120 mg/LHard 121–180 mg/LVery hard 181+ mg/L

At 112 mg/L, St. Louis Park is 48 mg/L below the typical Minnesota figure of 160. Of the 10 nearest cities we track, 5 have softer water and 5 have harder. The range nearby runs from 79 mg/L in Brooklyn Center to 254 in St. Anthony.

What 112 mg/L means at home

You may see faint white spots on glasses and shower doors after the water dries.

Scale builds up slowly. A kettle or coffee maker needs descaling now and then, maybe every few months.

Hardness is not a health problem, and EPA sets no limit for it. It is a matter of scale and soap.

What to do about it

Optional. Plenty of households at this level live with it and descale the kettle now and then.

Water softener

Worth a look if spots on glass bother you, or if your tankless water heater manual asks for softer water.

Carbon filter

Improves taste and removes chlorine. It leaves calcium and magnesium in place.

Softener size for St. Louis Park

3 people × 75 gallons a day × 6.5 gpg = 1,474 grains a day. A 24,000-grain unit regenerates about every 16 days.

Size it for your household

EPA record for St. Louis Park's water system

Saint Louis Park · PWSID MN1270050

No health-based violations since 2016

Serves about 50,010 people from groundwater.

Health-based
0
Monitoring or reporting
0
Open now
0

Health-based means a contaminant above its legal limit or a missed treatment step. Monitoring and reporting violations are late or missing tests and notices. Source: EPA ECHO, 2026Q3 export, violations with periods starting 2016 or later. Full EPA record.

Questions

Is St. Louis Park water hard?

Somewhat. It measures about 112 mg/L (6.5 grains per gallon), which the USGS classes as moderately hard.

What is the water hardness in St. Louis Park in grains per gallon?

About 6.5 gpg. One grain per gallon equals 17.1 mg/L, so 112 mg/L divided by 17.1 gives 6.5.

What size water softener do I need in St. Louis Park?

For 3 people using 75 gallons each per day, 6.5 gpg works out to about 1,474 grains a day. A 24,000-grain softener covers that with a regeneration about every 16 days.

Has the St. Louis Park water system had EPA violations?

EPA records show no health-based violations for Saint Louis Park since 2016.

Nearby cities

All 57 cities in Minnesota

Hardness data: TapWaterData US Water Hardness (utility report, March 12, 2025), CC BY 4.0. Population: US Census Bureau. Violations: EPA ECHO. How we use them.