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Water Hardness in 08691

Hamilton, New Jersey · Mercer County

58 PPM
3.4 GPG
Soft
0Soft60120180300+
Verified — Annual Water Quality Report

Dataset updated March 9, 2026Matched to 25 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 25 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 verified treated-water sources
25 matched systems total for this ZIP; treated-water reports are prioritized when available.
Water source profile
Primarily surface water
Surface-water hardness can shift with reservoirs, runoff, season, and treatment. 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 08691

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.

25 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.
Trenton Water Works
NJ1111001
Slightly Hard
60 PPMsurface water217,000 servedVerified — Annual Water Quality Report
Source water: 85 PPM
Aqua Nj - Blackwood
NJ0415002
Slightly Hard
60 PPMsurface water44,396 servedVerified — Annual Water Quality Report
Source water: 43 PPM
Aqua Nj - Hamilton Square
NJ1103001
Slightly Hard
60 PPMsurface water39,128 servedVerified — Annual Water Quality Report
Source water: 43 PPM
Aqua Nj - Phillipsburg
NJ2119001
Soft
43 PPMsurface water26,686 servedHigh Confidence — USGS Monitoring
East Windsor Mua
NJ1101002
Slightly Hard
60 PPMgroundwater25,000 servedVerified — Annual Water Quality Report
Source water: 56 PPM
Showing the first 5 systems. Expand to review all matched systems.

Nearby Zip Codes

085616008690600862060085017208520600855060086196008610600862960085156708555720860960

What This Means For You

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

Your Water Is Soft

Your water hardness is in the soft range. You likely don't need a water softener. Enjoy your naturally soft water!

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 Hamilton, NJ (08691).

Submit Your Data

Frequently Asked Questions

Is the water hard in Hamilton, NJ (08691)?

The average water hardness in 08691 is 58 PPM (3.4 GPG), which is classified as soft.

Do I need a water softener in 08691?

At 58 PPM, your water is relatively soft. A water softener is generally not necessary.

Is hard water in 08691 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 08691?

Zip code 08691 in Hamilton, New Jersey is served by 25 water systems.

Learn More About Your Water

Water Hardness Scale: PPM and GPG Chart

Use the USGS water hardness scale to compare PPM, GPG, and mg/L levels from soft to very hard water.

10 min read

How to Test Water Hardness at Home

Compare free lookups, soap tests, test strips, liquid drop kits, and lab tests for measuring water hardness.

8 min read