Drinking Water Quality

The Snohomish School District has had a drinking water quality monitoring program in place since 2016. In collaboration with the Washington State Department of Health, all schools and administrative buildings are tested on a regular cycle by a third-party testing company. The most recent round of testing was completed in late May/early June 2025 at all district schools and facilities.

Please contact the district’s Operations Department at 360-563-7230. For school-specific questions, please reach out to your school principal.

According to the U.S. Environmental Protection Agency (EPA), lead is a naturally occurring metal that can also enter the environment through human activity. Today, most lead exposure comes from legacy sources - materials or practices used in the past. Common sources of lead exposure include:

• Lead-based paint in older buildings
• Airborne lead from industrial emissions
• Soil contaminated by past use of leaded gasoline or deteriorating lead-based paint
• Certain imported products such as candies, medicines, dishes, toys, jewelry, plastics, or items made with or near lead
• Drinking water that travels through lead-containing pipes or plumbing fixtures

The U.S. Environmental Protection Agency (EPA) has set a guideline recommending that schools take action when lead levels in drinking water exceed 15 parts per billion (ppb). In Washington state, the Snohomish School District follows RCW 28A.210.410, which sets a more protective action level requiring steps be taken when lead levels exceed 5 parts per billion (ppb).

It’s important to understand that these action levels are not health-based limits. Instead, they serve as precautionary thresholds that signal the need to reduce lead exposure in drinking water, especially for children.

Lead can get into drinking water in two primary ways:

• It may be present in the original water source, such as through contaminated runoff
• More commonly, it enters through interactions between water and plumbing materials

While public water systems in our area are required to meet strict federal and state standards and routinely test their water sources to ensure safety, lead can still be introduced as water travels through the distribution system. This includes the network of pipes carrying water from the source to homes, schools, and businesses.

The most common sources of lead in drinking water are:

•  Older interior plumbing
• Soldered joints
• Brass fittings
• Fixtures made with or containing lead-based materials

These materials can corrode over time, especially if the water is corrosive, allowing lead to leach into the water supply.

Drinking water testing begins with collecting samples from specific types of fixtures, such as drinking fountains, water bottle filling stations, and food preparation sinks or sprayers. These fixtures are prioritized because they are most likely to be used for drinking or food-related purposes.

The samples are then sent to a certified laboratory for analysis. The lab tests the water for the presence of lead and reports the results in parts per billion (ppb). These results help determine whether action is needed to reduce lead levels and ensure water quality meets health and safety guidelines.

Specific testing protocols are used to help identify the source of elevated lead levels. Pinpointing the source allows for appropriate and effective corrective actions.

Testing may include the following:

• Public water source - Water providers conduct regular testing to ensure the source water meets federal and state standards.
• Water distribution system (before entering the building) - Sampling at the point where water enters a school or residence from the main line can help determine if the issue lies in the underground pipes. This type of testing is costly and typically conducted only if other testing does not reveal the source of lead.
• Internal building plumbing - A flush sample collected after running the tap for 30 seconds helps evaluate lead levels in the pipes behind walls or within the building's internal plumbing system.
• Fixtures, faucets, fountains, and supply lines: A first-draw sample is taken after water has remained stagnant in a fixture for 8 to 18 hours. This test identifies lead that may be leaching from fixtures, fittings, or short supply lines closest to the outlet.

By using these targeted sampling methods, experts can determine the most likely source(s) of lead and take the appropriate steps to address them.

When elevated lead levels are detected, the response depends on the source of the lead. The Snohomish School District consults with the Washington State Department of Health to determine the most appropriate remedial actions.

If the source is external to the building (such as fixtures or supply lines), common corrective steps may include:

• Flushing the water lines
• Cleaning faucet aerators to remove accumulated particles
• Replacing fixtures and/or sections of the supply line

If the lead is coming from interior plumbing within the building, solutions can be more complex and may involve:

• Installing certified filter systems
• Replacing or lining interior pipes

After corrective actions are implemented, follow-up water samples are collected and tested by a certified laboratory. If lead levels remain above the action threshold, additional steps are taken to further reduce exposure. This cycle of remediation and retesting continues until lead levels fall below the action level, confirming that the measures taken have been effective.

While schools take steps to ensure water quality, drinking water at home can also be a source of lead exposure - especially in older homes.

The Washington State Department of Health recommends the following actions:

• If your home was built before the mid-1940s, consider running your tap for at least two minutes if the water has been sitting in the pipes for six hours or more. This helps flush out any lead that may have leached into the water.
• In newer homes, if you’re still concerned about lead, run the water until it feels noticeably colder. This indicates fresh water from the main line.
• Always use cold water for drinking, cooking, and preparing baby formula. Hot water is more likely to contain lead from pipes or fixtures.
• Clean faucet screens and aerators regularly to remove trapped lead particles or debris.
• When building or remodeling, use only plumbing materials labeled “lead-free.”

These simple steps can help reduce your family’s potential exposure to lead in drinking water.

Please visit the Washington State Department of Health web page on lead frequently asked questions and resources and the U.S. Environmental Protection Agency (EPA) web page on lead in drinking water.