Water Hardness in 95451
Kelseyville, California · Lake County
Dataset updated March 9, 2026Matched to 7 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology
How this ZIP reading is built
This ZIP reading is built from 7 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.
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 95451
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.
| Water System | Source | Hardness | Pop. Served |
|---|---|---|---|
| Hidden Valley Lake Csd CA1710015 | groundwater | 235 PPM Hard | |
| Mt. Konocti Mutual Water Company CA1710014 | surface water | 157 PPM Moderately HardUSGS estimate: 125 PPM | |
| Buckingham Park Water District CA1710011 | surface water | 148 PPM Moderately HardUSGS estimate: 125 PPM | |
| Harbor View Mutual Water Company CA1700568 | surface water | 125 PPM Moderately Hard | |
| Clear Water Mutual Water Company CA1700546 | surface water | 140 PPM Moderately HardUSGS estimate: 125 PPM |
Nearby Zip Codes
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.
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 Kelseyville, CA (95451).
Frequently Asked Questions
Is the water hard in Kelseyville, CA (95451)?
The average water hardness in 95451 is 197 PPM (11.5 GPG), which is classified as hard.
Do I need a water softener in 95451?
With hardness of 197 PPM, a water softener is recommended for homes in 95451.
Is hard water in 95451 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 95451?
Zip code 95451 in Kelseyville, California is served by 7 water systems.
Learn More About Your Water
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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