Quick answer
Much of Snohomish County's drinking water comes from Spada Lake on the Sultan River, treated by the City of Everett. Everett's reports show low hardness and a pH that is adjusted with soda ash to make the water less corrosive. In general, soft, low-mineral water makes less scale but can be more corrosive to some metals, which is why utilities treat it.
Where much of the county's water comes from
The City of Everett's drinking water quality report says its water comes from Spada Reservoir, about 30 miles east of Everett at the headwaters of the Sultan River, and that the reservoir holds 50 billion gallons. The report says Everett treats water for about 670,000 people, which it puts at 75 percent of businesses and households in Snohomish County, and that it supplies most of the water systems in the county.
Snohomish County PUD's report says most of the water it delivers in its systems is purchased from Everett and comes from the same reservoir. The PUD also runs its own treatment facility for two wells that serve part of the Lake Stevens system, with that water blended with Everett's. Not every county resident is on the Everett supply, so your own utility's report is the one that matters for your address.
How the water is treated
Snohomish County PUD's report describes Everett's treatment as coagulation and advanced filtration to remove particles, followed by chlorine for disinfection and fluoride for dental protection. For its own Lake Stevens wells, the PUD says it removes iron and manganese, chlorinates, and fluoridates to match Everett's level before blending.
What the reports say about pH and corrosion control
Everett's 2024 report says soda ash is added to raise pH and alkalinity, which reduces the water's corrosivity. Washington State requires a minimum daily average pH of 7.4. The report gives an average pH of 7.6 for 2024, a lowest daily average of 7.3, and notes that the daily average fell below 7.4 on two nonconsecutive days at one clearwell discharge point and on one day at another. It also states the limit is no more than nine such days in six months.
Everett's separate detailed water quality summary gives a distribution system pH average of 8.1 across 26 monitoring locations, with a range of 7.7 to 9.3, and says pH varies by location and should be measured at your own tap. The PUD's report states that Everett adjusts the water's pH to reduce its corrosiveness, which lowers the chance that lead and copper leach from household plumbing.
How the reports describe hardness
Neither utility's main report uses the word soft. Everett's detailed summary gives total hardness averaging 12.5 parts per million as calcium carbonate, with a range of 10.2 to 15.8, and alkalinity averaging 17.1 parts per million. The USGS classifies water of 0 to 60 mg/L as soft, so those numbers fall well inside that category.
The PUD's Lake Stevens table, which reflects a blend of Everett water and well water, lists a wider hardness range of 9 to 89 parts per million with an average of 73. Hardness can therefore differ across the county depending on the blend. Check the report from your own water supplier.
What low-mineral water can mean for plumbing in general
The EPA's lead guidance explains that corrosion is worse when water is acidic or low in minerals, and that protective mineral scales inside pipes can reduce corrosion. The EPA's Lead and Copper Rule requires water systems to use corrosion control treatment so water is less corrosive to the plumbing it touches. This is the reasoning behind the pH adjustment in Everett's report. It is a general principle, not a finding about any particular home or pipe.
The practical point is that the utility handles what it can before the water reaches your property. Everett and the PUD both state that they cannot control the materials in household plumbing. What happens inside the home depends on the pipes, fittings and fixtures the water meets, and on how long it sits.
Lead and copper results in the reports
Everett's 2024 tap sampling covered 109 homes. The report gives a lead 90th percentile of 4 parts per billion against a 15 ppb action level, with 2 homes (1.8 percent) above the action level, and a copper 90th percentile of 0.080 ppm against a 1.3 ppm action level, with none above it. Everett reports that its inventory found no lead service lines. The next required sampling is in 2027.
The PUD's 2024 report says it found no lead service lines among more than 23,000 services it inventoried and that water tested before entering household plumbing had even lower lead and copper levels than tap samples, so household plumbing may be the source of any lead or copper detected. Both utilities advise flushing the tap for 30 seconds to two minutes if water has sat for several hours before using it for drinking or cooking. The EPA also advises using cold water for drinking and cooking, having your water tested if you are concerned, and cleaning faucet aerators regularly.
Scale, water heaters and what the reports do not say
USGS explains that when hard water is heated, calcium carbonate can form scale that shortens equipment life, raises heating costs, reduces the efficiency of electric water heaters and can clog pipes over time. Given Everett's low reported hardness, that particular kind of scale is not a feature of the numbers in its report. That said, hardness varies by blend, and a water heater's condition depends on its age, installation and maintenance, which follow the manufacturer's instructions.
It is worth being clear about the limits. Neither report mentions water heaters, repiping or pipe failures. Neither one says that local water damages plumbing, and we are not claiming that. The reports describe treatment aimed at making water less corrosive, and the plumbing implications above are general knowledge from the EPA and USGS.
Practical steps for homeowners
These steps apply wherever your water comes from.
- Read the water quality report from your own supplier. It is published yearly.
- Flush the tap for 30 seconds to two minutes if water has sat for hours, as both utilities advise.
- Clean faucet aerators regularly, as the EPA suggests.
- Watch for blue-green staining, pinhole leaks, discolored water or falling pressure, and have them checked rather than waiting.
- Know where your main shutoff is.
When to call Pyper Plumbing
Water quality questions about what is in the water are for your utility. Questions about your pipes and fixtures are where Pyper can help. We offer leak detection and repair, water heater service and repiping, and emergency repair, in Snohomish, Skagit, Whatcom and Island counties.
Call if you find a leak, a repeated pinhole in a copper line, a water heater that is leaking or failing, or pipes that are visibly corroded. A plumber can inspect what is in your home. We do not diagnose the cause from a utility report alone.
Common questions
Does most of Snohomish County get water from Everett?
Everett's report says it treats water for about 670,000 people, which it describes as 75 percent of businesses and households in Snohomish County. Snohomish County PUD says most of the water in its systems is purchased from Everett. Your own supplier's report shows your specific source.
Is Everett water soft?
Everett's reports do not use the word soft, but its detailed summary lists total hardness averaging 12.5 ppm. USGS classifies 0 to 60 mg/L as soft. Hardness can differ in blended systems such as the PUD's Lake Stevens area.
Why does Everett adjust the water's pH?
Everett's report says soda ash is added to raise pH and alkalinity, reducing corrosivity. The EPA explains that corrosive water can release lead and copper from plumbing, which is why corrosion control is required.
Do these reports say local pipes are failing?
No. The reports reviewed describe treatment, test results and general precautions. They make no claim about pipe failures in Snohomish County.
Sources
Facts in this guide come from the following references. Local rules and manufacturer instructions can differ, so follow your utility and your equipment manual.
- 2024 Drinking Water Quality Report (City of Everett)
- 2024 Detailed water quality summary (City of Everett)
- 2024 Water Quality Report (Snohomish County PUD)
- Basic information about lead in drinking water (U.S. EPA)
- Hardness of water (USGS Water Science School)
This guide is general information, not a substitute for an on-site inspection. If you smell natural gas, leave the building and call 911 or your gas utility. Pyper does not perform gas line work.
