Sammamish Plateau Water & Sewer
As of July 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
WA / Sammamish
WA · Tap water records
Sammamish tap water, in plain English
Here is what the EPA's own data shows about tap water in Sammamish. According to EPA SDWIS data retrieved July 2026, Sammamish is served by 4 active community water systems, together reported to serve about 88,088 people.
As of July 2026, EPA records show 61 violations across the community water system(s) serving Sammamish, going back to the earliest EPA record. None were health-based; the records are monitoring or reporting violations (a required test or report was late or missed). Each is listed by system below, with its status.
- 4Community water systems
- ~88,088People served (EPA-reported)
- July 2026EPA records reviewed through
What the EPA has on record, by system
Ne Sammamish Sewer & Water District
- Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times in January 2022. All have since returned to compliance, per EPA records.
Mayfield Rv Park
- Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 8 times between July 2013 and July 2023. All have since returned to compliance, per EPA records.
- Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 5 times between September 2021 and January 2023. All have since returned to compliance, per EPA records.
- Monitoring Nitrate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2015. All have since returned to compliance, per EPA records.
- Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 3 times between July 2005 and January 2012. All have since returned to compliance, per EPA records.
- Monitoring Arsenic: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Barium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Cadmium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Chloride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Chromium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring CYANIDE: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Fluoride: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Iron: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Manganese: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Mercury: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Nickel: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Nitrite: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Selenium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Silver: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Sodium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Antimony, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Beryllium, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Thallium, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Zinc: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
- Monitoring Hardness, Total (as CaC03): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in January 2011. All have since returned to compliance, per EPA records.
Terrace Square Apts
As of July 2026, EPA records show no reported violations for this system in the period covered. This is not a guarantee about every substance, or about the water inside your home's plumbing.
What this means
A health-based violation means a contaminant was recorded above the limit the EPA tracks for it. A monitoring or reporting violation means a required test or report was late or missed — not that a contaminant was measured above a limit. “Returned to compliance” means the EPA recorded the issue as resolved.
This page summarizes the EPA's own records and does not assess whether your water is safe to drink. For the most current details, you can verify every record directly with the EPA, and contact your water system with questions.
Source: U.S. EPA Envirofacts SDWIS, retrieved July 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.