Water Hardness in Grass Valley, CA

Q: Do I need a water softener in Grass Valley, CA?

At a citywide weighted average of 36 PPM, Grass Valley has relatively soft water. A water softener is generally not necessary.

Q: How many water systems serve Grass Valley, CA?

Grass Valley, California has 10 matched water systems across 2 zip codes.

California · 2 zip codes · 10 matched water systems

8 PPM

0.5 GPG

Soft

0Soft60120180300+

Verified — State Lab Tested

City avg (weighted): 36 PPM

Dataset updated March 9, 202610 matched water systems in the city rollupIndividual systems and ZIPs can differ. Methodology

System used for this reading

Nevada Id - E. George, Banner Mountain

CA2910004

Water source: surface water

Source year: 2025

Serves: 17,154

USGS environmental estimate: 27 PPM

Source context

How this city reading is built

This city reading is a weighted rollup across 10 matched water systems and 2 ZIP codes. Citywide readings are useful for comparison, but individual utility zones and ZIPs can differ.

Source basis

6 verified treated-water sources

10 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

Report years 2024-2025

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 Grass Valley

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

10 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.

Water System	Source	Hardness	Pop. Served	Data Source
Truckee-Donner Pud, Main CA2910003	groundwater	66 PPM Slightly Hard	36,730	High Confidence — USGS Monitoring
Nevada Id - E. George, Banner Mountain CA2910004	surface water	8 PPM Soft USGS estimate: 27 PPM	17,154	Verified — State Lab Tested(2025)
Nevada Id - Loma Rica CA2910006	surface water	10 PPM Soft USGS estimate: 27 PPM	14,072	Verified — State Lab Tested(2024)
Nevada Id - Lake Wildwood CA2910023	surface water	15 PPM Soft USGS estimate: 27 PPM	9,108	Verified — State Lab Tested(2024)
Nevada Id - Lake Of Pines CA2910014	surface water	17 PPM Soft USGS estimate: 27 PPM	6,870	Verified — State Lab Tested(2025)

Truckee-Donner Pud, Main

CA2910003

Slightly Hard

66 PPMgroundwater36,730 servedHigh Confidence — USGS Monitoring

Nevada Id - E. George, Banner Mountain

CA2910004

Soft

8 PPMsurface water17,154 servedVerified — State Lab Tested

Source water: 27 PPM

Nevada Id - Loma Rica

CA2910006

Soft

10 PPMsurface water14,072 servedVerified — State Lab Tested

Source water: 27 PPM

Nevada Id - Lake Wildwood

CA2910023

Soft

15 PPMsurface water9,108 servedVerified — State Lab Tested

Source water: 27 PPM

Nevada Id - Lake Of Pines

CA2910014

Soft

17 PPMsurface water6,870 servedVerified — State Lab Tested

Source water: 27 PPM

Showing the first 5 systems. Expand to review all matched systems.

Zip Codes in Grass Valley, CA

9594534 9594939

What This Means For You

Recommendations are based on the displayed 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 Grass Valley, CA.

Submit Your Data

Frequently Asked Questions

How hard is the water in Grass Valley, CA?

The citywide weighted average water hardness in Grass Valley, CA is 36 PPM (2.1 GPG), classified as soft. This is based on 10 matched water systems. The gauge highlights Nevada Id - E. George, Banner Mountain, a verified treated-water system, because individual systems can differ from the citywide average.

Do I need a water softener in Grass Valley, CA?

At 36 PPM, the citywide average is relatively soft. A water softener is generally not necessary.

Is hard water in Grass Valley, CA 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 Grass Valley, CA?

Grass Valley, California is served by 10 matched water systems across 2 zip codes.

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.

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How to Test Water Hardness at Home

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

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