PROSSER CITY OF

Prosser, WA · ~6,211 people served

Check your exact address → Prosser overview

100

Excellent

PurityRadar safety score

PWSID

WA5369750

State

Washington

City

Prosser

Population served

6,211

Primary source

Groundwater

Score history

No change since tracking began Jun 18, 2026.

Jun 18, 2026 · score 100 Jun 18, 2026 · score 100

2 score updates logged since tracking began Jun 18, 2026. Each future EPA re-score adds a point.

PFAS & contaminant readings

Latest detections from EPA’s UCMR5 monitoring (through Dec 2024). Levels in parts per trillion (ppt).

Lithium

21,000 ppt

limit —

No federal limit

Violations & enforcement

Violations on record

Unaddressed

Health-based

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Mar 2024. Official EPA record →

Monitoring & reporting · Nitrate began Jan 2023 Resolved

Other · EPA contaminant 7000 began Jul 2014 Resolved

Monitoring & reporting · Lead & Copper Rule began Jan 2014 Resolved

Monitoring & reporting · Lead & Copper Rule began Jan 2010 Resolved

Monitoring & reporting · Fluoride began Jul 2008 Resolved

Monitoring & reporting · Fluoride began Oct 2004 Resolved

Recent enforcement actions

State action · SOX Mar 2024
State action · SOX Aug 2017
State action · SOX Oct 2014
State action · SOX Sep 2013
State action · SOX Sep 2009
State action · SOX Sep 2009
State action · SOX Sep 2009
State action · SOX Sep 2009

Area water-quality monitoring

Environmental monitoring (rivers, wells, intakes) recorded in this system’s service area in the EPA/USGS Water Quality Portal since 2018 — source/ambient water, not finished tap water. Context for the watershed, not a reading from your tap.

ContaminantMedian · max · samples

Nitrate

1 station · latest Sep 2020

0.906 · max 1.45 mg/l as N · 18

Source: Water Quality Portal (EPA/USGS/state agencies). Values are as-reported and aren’t health thresholds.

This profile is built from EPA public records for system WA5369750 — SDWIS violations and UCMR5 PFAS sampling. The score is system-level and can’t account for your home’s plumbing (older pipes can add lead at the tap). For health decisions, check your exact address, read the utility’s Consumer Confidence Report, and confirm with your provider.