Water Hardness in New Jersey (NJ)

New Jersey has an average water hardness of 120 ppm (7 grains per gallon), which is classified as Slightly Hard . At this level, New Jersey residents experience minimal hard water issues. A water softener is generally not necessary, though some homeowners prefer the feel and cleaning performance of softened water. Water hardness varies between cities — from 30 ppm in Newark to 175 ppm in Cherry Hill.

State Average 120 ppm 7 gpg
Hardness Level Slightly Hard No softener needed
Hardest City Cherry Hill 175 ppm
Softest City Newark 30 ppm

Water Hardness by City in New Jersey

The table below shows water hardness data for 8 cities in New Jersey, sorted from hardest to softest. Click any city name for detailed information including water source, treatment recommendations, and estimated hard water costs.

City Hardness (PPM) Grains/Gallon Level Water Source pH TDS Utility
Cherry Hill 175 ppm 10.2 gpg Moderately Hard Ground 7.7 275 New Jersey American Water
Atlantic City 155 ppm 9.1 gpg Moderately Hard Ground 7.6 245 Atlantic City Municipal Utilities Authority
Toms River 140 ppm 8.2 gpg Moderately Hard Ground 7.5 220 New Jersey American Water
Trenton 110 ppm 6.4 gpg Slightly Hard Mixed 7.4 170 Trenton Water Works
Woodbridge 100 ppm 5.8 gpg Slightly Hard Mixed 7.3 155 Middlesex Water Company
Edison 90 ppm 5.3 gpg Slightly Hard Mixed 7.3 140 Middlesex Water Company
Jersey City 35 ppm 2 gpg Soft Surface 7.1 55 Suez Water New Jersey
Newark 30 ppm 1.8 gpg Soft Surface 7 48 City of Newark Water Department
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Understanding Water Hardness in New Jersey

Water Sources in New Jersey

Many cities in New Jersey rely on groundwater from wells and aquifers as their primary water source. Groundwater tends to be harder than surface water because it spends more time in contact with limestone, dolomite, and other mineral-rich rock formations deep underground. This prolonged contact allows more calcium and magnesium to dissolve into the water, resulting in higher hardness levels.

Hardness Variation Across New Jersey

Water hardness in New Jersey ranges from 30 ppm in Newark to 175 ppm in Cherry Hill — a difference of 145 ppm. This variation means that treatment recommendations differ significantly between cities. Even the hardest water in New Jersey is moderate enough that a water softener is optional rather than essential, though homeowners who value spotless dishes and softer-feeling water may still find one worthwhile. Meanwhile, Newark enjoys naturally soft water that needs no treatment at all — an advantage that saves residents money on both equipment and ongoing maintenance.

Recommended Treatment for New Jersey Water

Based on the average water hardness of 120 ppm in New Jersey, a water softener is not strictly necessary, but some homeowners may prefer treated water. The most effective treatment options for New Jersey's water hardness level include:

How New Jersey Compares to Other States

Below is a comparison of New Jersey with five states that have similar average water hardness levels. Understanding how your state compares can help you gauge whether your water is typical for the region or unusually hard or soft.

State Avg Hardness Level Cities
New Jersey (NJ) 120 ppm Slightly Hard 8
District of Columbia (DC) 120 ppm Slightly Hard 7
West Virginia (WV) 120 ppm Slightly Hard 8
Maryland (MD) 115 ppm Slightly Hard 7
Delaware (DE) 110 ppm Slightly Hard 7
Kentucky (KY) 130 ppm Moderately Hard 8

Find Your City's Water Hardness

Use our water hardness lookup tool to find your specific city in New Jersey, or browse all 50 states to compare water hardness across the country. If your water is hard, visit our treatment solutions guide to find the right softener or conditioner for your home.