Water Softeners & Filtration in Spokane, WA

Water in Spokane at a Glance

Most Spokane homes are on City of Spokane water drawn from the Spokane Valley–Rathdrum Prairie Aquifer. It is clean, well-protected groundwater, but it is hard: typically 7–10 grains per gallon at the tap. That's why the most common Spokane install is a water softener, often paired with a reverse osmosis system at the kitchen sink. Homes on the city's edges that rely on private wells need a full water test first, because wells in parts of Spokane County can carry uranium or arsenic.

Local Water Facts

Main water source	Spokane Valley–Rathdrum Prairie Aquifer (EPA Sole Source Aquifer since 1978)
Typical hardness	7–10 grains per gallon ("hard" to "very hard")
Disinfection	Chlorine
Private wells	Common on the north and south edges of the city; not regulated by the state
Phone	(509) 286-1223

Last reviewed October 2026. Sources listed below.

What's in Spokane tap water

The City of Spokane pumps its water from wells into the Spokane Valley–Rathdrum Prairie Aquifer, which the EPA designated a Sole Source Aquifer in 1978. The USGS estimates it supplies more than 500,000 people across Spokane and Kootenai counties. The water moves quickly through glacial gravel and arrives clean, so the city needs very little treatment beyond chlorination.

The trade-off is minerals. As the water travels through that gravel it picks up calcium and magnesium, and at the tap it typically tests at 7–10 grains per gallon. Anything over 7 gpg is classified as hard. In practice that means white scale on faucets and glass shower doors, spotty dishes, and shorter lives for water heaters, dishwashers and washing machines.

The city publishes its test results every year in its Consumer Confidence Report. We also test hardness, chlorine and iron at your tap during a free in-home visit, so the system we size matches your house rather than a citywide average.

What we usually recommend for Spokane homes

Water softener at the main line to remove hardness. We size it to your actual hardness reading and household size, not a showroom default. See whole-house water treatment.
Whole-house carbon filtration if you notice chlorine taste or smell in showers and at every tap.
Reverse osmosis at the kitchen sink for drinking and cooking water. See drinking water systems.
Private well on the city's edge? Start with a full water test before choosing equipment. Iron, manganese, uranium and arsenic each call for different treatment. See our PNW well water guide.

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Spokane Water Questions

Common questions we hear from homeowners in Spokane

Is Spokane water hard?

Yes. Spokane water from the Spokane Valley–Rathdrum Prairie Aquifer typically tests at 7–10 grains per gallon, which is classified as hard to very hard. You will usually see it as white scale on faucets, showerheads and glass.

Do I need a water softener in Spokane?

Most Spokane homes benefit from one, because 7–10 gpg hardness shortens the life of water heaters and appliances and increases soap use. Below about 5 gpg a softener is optional. A free in-home test gives you the actual reading at your tap before you decide.

Does the City of Spokane use chlorine or chloramine?

Spokane disinfects with chlorine. Chlorine is straightforward to remove with a standard whole-house carbon filter or a reverse osmosis system at the kitchen sink.

I live in Spokane but have a private well. What should I test for?

The Spokane Regional Health District recommends private well owners test their water, noting that some areas of Spokane County have elevated uranium and/or arsenic. A good starting panel covers bacteria, nitrate, arsenic, uranium, iron, manganese and hardness.