Water Hardness in Tennessee (TN)

Tennessee has an average water hardness of 110 ppm (6.4 grains per gallon), which is classified as Slightly Hard . At this level, Tennessee 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 60 ppm in Memphis to 170 ppm in Murfreesboro.

State Average 110 ppm 6.4 gpg
Hardness Level Slightly Hard No softener needed
Hardest City Murfreesboro 170 ppm
Softest City Memphis 60 ppm

Water Hardness by City in Tennessee

The table below shows water hardness data for 8 cities in Tennessee, 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
Murfreesboro 170 ppm 9.9 gpg Moderately Hard Ground 7.7 265 Murfreesboro Water Resources
Franklin 145 ppm 8.5 gpg Moderately Hard Ground 7.6 225 City of Franklin Water Management
Clarksville 110 ppm 6.4 gpg Slightly Hard Surface 7.4 170 Clarksville Gas and Water
Nashville 100 ppm 5.8 gpg Slightly Hard Surface 7.4 155 Metro Nashville Water Services
Knoxville 90 ppm 5.3 gpg Slightly Hard Surface 7.3 135 Knoxville Utilities Board
Chattanooga 80 ppm 4.7 gpg Slightly Hard Surface 7.2 120 Tennessee American Water
Johnson City 65 ppm 3.8 gpg Slightly Hard Surface 7.2 100 Johnson City Water and Sewer
Memphis 60 ppm 3.5 gpg Soft Ground 7.1 90 Memphis Light Gas and Water
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Understanding Water Hardness in Tennessee

Water Sources in Tennessee

The majority of cities in Tennessee draw their water from surface sources such as rivers, lakes, and reservoirs. Surface water generally contains fewer dissolved minerals than groundwater, which helps explain the overall hardness profile of the state. Cities that rely on surface water tend to have softer water because the water has less contact time with mineral-bearing rock formations underground.

Hardness Variation Across Tennessee

Water hardness in Tennessee ranges from 60 ppm in Memphis to 170 ppm in Murfreesboro — a difference of 110 ppm. This variation means that treatment recommendations differ significantly between cities. Even the hardest water in Tennessee 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. Memphis has the softest water in the state, though at 60 ppm it still contains some dissolved minerals.

Recommended Treatment for Tennessee Water

Based on the average water hardness of 110 ppm in Tennessee, a water softener is not strictly necessary, but some homeowners may prefer treated water. The most effective treatment options for Tennessee's water hardness level include:

How Tennessee Compares to Other States

Below is a comparison of Tennessee 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
Tennessee (TN) 110 ppm Slightly Hard 8
Delaware (DE) 110 ppm Slightly Hard 7
Louisiana (LA) 105 ppm Slightly Hard 8
Maryland (MD) 115 ppm Slightly Hard 7
Alabama (AL) 100 ppm Slightly Hard 8
District of Columbia (DC) 120 ppm Slightly Hard 7

Find Your City's Water Hardness

Use our water hardness lookup tool to find your specific city in Tennessee, 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.