Water Hardness in Sequim, WA
Washington · 1 zip codes · 25 matched water systems
Dataset updated March 9, 202625 matched water systems in the city rollupIndividual systems and ZIPs can differ. Methodology
How this city reading is built
This city reading is a weighted rollup across 25 matched water systems and 1 ZIP code. Citywide readings are useful for comparison, but individual utility zones and ZIPs can differ.
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 Sequim
These systems are matched to Sequim, WA. Citywide readings are useful for comparison, but the system serving a specific address may differ from the city average.
| Water System | Source | Hardness | Pop. Served |
|---|---|---|---|
Port Angeles City Of WA5368550 | surface water | 23 PPM Soft | |
Sequim City Of WA5377620 | groundwater | 289 PPM Very Hard | |
Port Angeles Composite WA5343296 | surface water | 289 PPM Very Hard | |
West Sequim Bay Inc WA5354192 | groundwater | 289 PPM Very Hard | |
Crescent Water Assn WA5316020 | surface water | 289 PPM Very Hard |
Zip Codes in Sequim, WA
What This Means For You
Recommendations are based on the displayed hardness reading. Confirm your tap reading before sizing or buying treatment equipment.
Hard Water - Treatment Recommended
Your water is hard. Scale buildup is likely affecting your plumbing and appliances, reducing their lifespan and efficiency. A water softener is recommended to protect your home.
Recommended Products
Learn more: Do I Need a Water Softener? | Salt-Based vs Salt-Free | Size Calculator | 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 Sequim, WA.
Frequently Asked Questions
How hard is the water in Sequim, WA?
The citywide weighted average water hardness in Sequim, WA is 182 PPM (10.6 GPG), classified as hard. This is based on 25 matched water systems.
Do I need a water softener in Sequim, WA?
With a citywide average hardness of 182 PPM, a water softener is recommended for homes in Sequim. Confirm your tap reading before sizing equipment.
Is hard water in Sequim, WA 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 Sequim, WA?
Sequim, Washington is served by 25 matched water systems across 1 zip code.
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