Where does the water in 91406 come from?

Water for zip code 91406 in Van Nuys, California is provided by 25 water systems. Contact your local utility for specific source information, or check our detailed page for your area.

Water Hardness in 91406

Van Nuys, California · Los Angeles County

157 PPM

9.2 GPG

Moderately Hard

0Soft60120180300+

Verified - State Lab Tested

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

13 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

Report years 2023-2025

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 Serving 91406

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.

Water System	Source	Hardness	Pop. Served	Data Source
Los Angeles-City, Dept. Of Water & Power CA1910067	surface water	112 PPM Slightly Hard USGS estimate: 189 PPM	3,875,566	Verified - State Lab Tested(2024)
Long Beach Utilities Department CA1910065	surface water	103 PPM Slightly Hard	466,772	High Confidence - USGS Monitoring
Santa Clarita Valley Water Agency CA1910240	surface water	160 PPM Moderately Hard USGS estimate: 204 PPM	294,090	Verified - State Lab Tested(2023)
Gswc - Southwest CA1910155	surface water	189 PPM Hard	277,740	High Confidence - USGS Monitoring
San Gabriel Valley Water Co.-El Monte CA1910039	groundwater	290 PPM Very Hard USGS estimate: 197 PPM	248,000	Verified - State Lab Tested(2024)

Los Angeles-City, Dept. Of Water & Power

CA1910067

Slightly Hard

112 PPMsurface water3,875,566 servedVerified - State Lab Tested

Source water: 189 PPM

Long Beach Utilities Department

CA1910065

Slightly Hard

103 PPMsurface water466,772 servedHigh Confidence - USGS Monitoring

Santa Clarita Valley Water Agency

CA1910240

Moderately Hard

160 PPMsurface water294,090 servedVerified - State Lab Tested

Source water: 204 PPM

Gswc - Southwest

CA1910155

Hard

189 PPMsurface water277,740 servedHigh Confidence - USGS Monitoring

San Gabriel Valley Water Co.-El Monte

CA1910039

Very Hard

290 PPMgroundwater248,000 servedVerified - State Lab Tested

Source water: 197 PPM

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

Nearby Zip Codes

91411157 91405157 91335157 91343157 91402157 91316157 91325157 91401157 91436157 91403157 91356157 91324157

What This Means For You

Use this ZIP 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.

Methodology Data sources How to test your 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 Van Nuys, CA (91406).

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Frequently Asked Questions

Is the water hard in Van Nuys, CA (91406)?

The average water hardness in 91406 is 157 PPM (9.2 GPG), which is classified as moderately hard.

Do I need a water softener in 91406?

With hardness of 157 PPM, a water softener is worth considering for homes in 91406.

Is hard water in 91406 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 91406?

Zip code 91406 in Van Nuys, California is served by 25 water systems.