Water Hardness in Durham, NC

North Carolina · 6 zip codes · 11 matched water systems

35 PPM
2 GPG
Soft
0Soft60120180300+
Verified - Annual Water Quality Report

City avg (weighted): 35 PPM

Dataset updated March 9, 202611 matched water systems in the city rollupIndividual systems and ZIPs can differ. Methodology

System used for this reading
Durham, City Of
NC0332010
Water source: surface water
Serves: 322,083
USGS environmental estimate: 39 PPM
City report

Is Durham, NC Water Hard or Soft?

The displayed hardness for Durham, NC is 35 PPM (2 GPG) from Durham, City Of, classified as soft. The citywide weighted average is 35 PPM.

Displayed reading
35 PPM
Soft
Local coverage
6 ZIPs
11 matched water systems
Source label
Annual Water Quality Report
Verified - Annual Water Quality Report

Water hardness is not a drinking-water safety score. It measures calcium and magnesium minerals, and address-level results can shift by pressure zone, supply blend, building plumbing, or private well.

Source context

How this city reading is built

This city reading is a weighted rollup across 11 matched water systems and 6 ZIP codes. Citywide readings are useful for comparison, but individual utility zones and ZIPs can differ.

Source basis
11 verified treated-water sources
11 matched systems total for this city; 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 in Durham

These systems are matched to Durham, NC. Citywide readings are useful for comparison, but the system serving a specific address may differ from the city average.

11 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.
Soft
35 PPMsurface water322,083 servedVerified - Annual Water Quality Report
Source water: 39 PPM
Soft
35 PPMgroundwater643 servedVerified - Annual Water Quality Report
Source water: 56 PPM
Crown Mhp
NC0241112
Soft
35 PPMgroundwater343 servedVerified - Annual Water Quality Report
Source water: 49 PPM
35 PPMgroundwater305 servedVerified - Annual Water Quality Report
Source water: 49 PPM
35 PPMgroundwater189 servedVerified - Annual Water Quality Report
Source water: 49 PPM
Showing the first 5 systems. Expand to review all matched systems.

Zip Codes in Durham, NC

What This Means For You

Use this city reading as a local planning estimate, not a final treatment specification. Hardness can vary by utility zone, seasonal blend, private well, and building plumbing. Confirm your tap reading with a utility report or home hardness test before sizing 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 Durham, NC.

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Frequently Asked Questions

How hard is the water in Durham, NC?

The citywide weighted average water hardness in Durham, NC is 35 PPM (2 GPG), classified as soft. This is based on 11 matched water systems.

Do I need a water softener in Durham, NC?

At 35 PPM, the citywide average is relatively soft. A water softener is generally not necessary.

Is hard water in Durham, NC 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 Durham, NC?

Durham, North Carolina is served by 11 matched water systems across 6 zip codes.

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