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Water Hardness in 49240

Grass Lake, Michigan · Jackson County

230 PPM
13.4 GPG
Hard
0Soft60120180300+
High Confidence — USGS Monitoring

Dataset updated March 9, 2026Matched to 4 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology

Source context

How this ZIP reading is built

This ZIP reading is built from 4 matched water systems. When more than one system is matched, the displayed value is weighted toward larger known service populations when that data is available.

Source basis
4 USGS-backed sources
4 matched systems total for this ZIP; USGS monitoring is used where treated-water reports are unavailable.
Water source profile
Primarily groundwater
Groundwater commonly picks up calcium and magnesium after contact with rock and soil. This profile is weighted by known population served across matched systems.
Data recency
March 9, 2026
Dataset rebuilt March 9, 2026; individual utility reporting years can vary.

Hardness is a mineral-content reading, not a drinking-water safety rating. Use it for scale, appliance, and softener decisions; check your utility report or test your tap before sizing treatment equipment. See how we calculate local readings.

Water Systems Serving 49240

These are the systems matched to this ZIP code. The displayed ZIP value is weighted toward larger known service populations when population data is available.

4 water systems
PWSID is the public water system identifier. Data Source shows whether the hardness value comes from a treated-water report, USGS monitoring, or a local estimate; source year is shown when available.
Jackson
MI0003470
Hard
230 PPMgroundwater33,165 servedHigh Confidence — USGS Monitoring
Summit Township
MI0006450
Hard
230 PPMgroundwater25,355 servedHigh Confidence — USGS Monitoring
Blackman Township
MI0000740
Hard
230 PPMsurface water21,222 servedHigh Confidence — USGS Monitoring
Grass Lake
MI0002830
Hard
225 PPMgroundwater1,986 servedHigh Confidence — USGS Monitoring

Nearby Zip Codes

What This Means For You

Recommendations are based on the displayed ZIP hardness reading. Confirm your tap reading before sizing or buying treatment equipment.

Know your water hardness?

If you've tested your water or have your utility's CCR report, share your reading to help us improve accuracy for Grass Lake, MI (49240).

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Frequently Asked Questions

Is the water hard in Grass Lake, MI (49240)?

The average water hardness in 49240 is 230 PPM (13.4 GPG), which is classified as hard.

Do I need a water softener in 49240?

With hardness of 230 PPM, a water softener is recommended for homes in 49240.

Is hard water in 49240 safe to drink?

Water hardness itself is a mineral-content reading, not a drinking-water safety rating. Calcium and magnesium are naturally occurring minerals, but you should check your utility's Consumer Confidence Report for contaminant and compliance information.

How many water systems serve 49240?

Zip code 49240 in Grass Lake, Michigan is served by 4 water systems.

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