Record-only indicator: A
Not a safety rating. Missing or old measurements can produce a high score.
Coverage: 0/1 mapped systems have a dated lead result; 0/1 have copper results; 1/1 have UCMR monitoring.
Public-record summary
Record-only indicator — incomplete or old records can produce a high score. A score of 100 is not a safety finding. Coverage: 0/1 mapped systems have a dated lead result; 0/1 have copper results; 1/1 have UCMR monitoring. Tap water quality in Mountlake Terrace, Washington (98043) receives an record-only indicator of A (Lower record-based concern) with a score of 85 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is 6 points below the Washington state average of 92. The area is served by Mountlake Terrace City Of, a surface water system providing water to approximately 26,402 people.
Grade A summarizes the records available to this model, not household safety. Missing, bounded or old measurements can produce a high score, including 100. Review coverage, dates and the current utility report before interpreting this indicator.
Common Questions
The record-only indicator is A (85/100). It cannot determine whether your tap water is safe. Missing, bounded or old measurements can produce a high score. Check the coverage and sampling dates below and your utility's current notices.
ZIP code 98043 is served by 1 water system using surface water sources, providing water to approximately 26,402 people. Surface water systems are more susceptible to contamination from agricultural runoff, industrial discharge, and weather events, but typically undergo more extensive treatment including filtration and disinfection.
No dated lead result was found for these mapped systems in the published dataset. This does not establish that lead is absent. Ask your utility for its current report and testing options.
No PFAS ("forever chemicals") were detected in water systems serving Mountlake Terrace, Washington during the most recent EPA monitoring period (UCMR5). However, not all water systems have been tested for all PFAS compounds, and new contamination can occur over time.
Water systems serving Mountlake Terrace, Washington have received 3 violations in the last 5 years. Violations can range from paperwork issues (monitoring & reporting) to serious health-based violations where contaminant levels exceeded safe limits. Review the violation details above for specifics.
This public-record indicator cannot select household treatment. Confirm your supplier, current utility report and tap-testing results first; match any treatment to a certified contaminant-reduction claim and follow its maintenance instructions.