Water Quality Report · Updated October 07, 2026
Auburn City of
Auburn City of delivers tap water graded B (75/100) by TapWaterSafety.org. The utility serves approximately 107,655 residents in Auburn, Washington using groundwater. The most significant water quality concerns are: Arsenic significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline.
Is Auburn tap water safe to drink?
Auburn City of delivers tap water that earns a grade of B (75/100) from TapWaterSafety.org — a good rating, with only minor concerns relative to health-based guidelines.
The utility serves 107,655 residents in Auburn, drawing from groundwater.
Public testing data identifies 13 contaminants in this water above EWG's health-based guidelines, including: Arsenic, Haloacetic acids (HAA5), Total trihalomethanes (TTHMs), Bromodichloromethane, Dibromochloromethane, Haloacetic acids (HAA9), Chromium (hexavalent), Nitrate, Nitrate and nitrite, Dibromoacetic acid, Chloroform, Dichloroacetic acid, Trichloroacetic acid. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
EPA compliance record
Official U.S. EPA records for Auburn City of (system ID WA5303350) for the last 3 years. Checked 2026-10-07.
| Rule | Type | Since | Status |
|---|---|---|---|
| Nitrate Rule | Missed testing or reporting | 01/01/2025 | Resolved |
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Quick actions for Auburn residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for Auburn City of.
Arsenic significantly above health guideline
Moderate concernArsenic detected at 0.395 ppb, 99x above the EWG health guideline of 0.004 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 6.83 ppb, 68x above the EWG health guideline of 0.1 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 10.2 ppb, 68x above the EWG health guideline of 0.15 ppb.
Contact Auburn City of
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for Auburn
Filters matched to the specific contaminants in this water supply.
Reverse osmosis certified for arsenic (NSF/ANSI 58)
$429-$599Reverse osmosis certified under NSF/ANSI 58 for arsenic is the most reliable home option.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
Score breakdown
This utility's overall score of 75/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Arsenic Heavy metal |
0.395 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 99× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
6.83 ppb | 0.1 | 60.0 | 60 | — | — | — | 68× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
10.2 ppb | 0.15 | 80.0 | 100 | — | — | — | 68× over |
| Bromodichloromethane Disinfection byproduct |
2.65 ppb | 0.06 | — | — | — | — | — | 44× over |
| Dibromochloromethane Disinfection byproduct |
2.3 ppb | 0.1 | — | — | — | — | — | 23× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
0.65 ppb | 0.06 | — | — | — | — | — | 11× over |
| Chromium (hexavalent) Heavy metal |
0.201 ppb | 0.02 | — | — | — | — | — | 10× over |
| Nitrate Inorganic |
1.44 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 10× over |
| Nitrate and nitrite Inorganic |
1.4 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 10× over |
| Dibromoacetic acid Disinfection byproduct |
0.297 ppb | 0.03 | — | — | — | — | — | 9.9× over |
| Chloroform Disinfection byproduct |
3.53 ppb | 0.4 | — | — | — | — | — | 8.8× over |
| Dichloroacetic acid Disinfection byproduct |
1.76 ppb | 0.2 | — | — | — | — | — | 8.8× over |
| Trichloroacetic acid Disinfection byproduct |
0.217 ppb | 0.1 | — | — | — | — | — | 2.2× over |
| Bromoform Disinfection byproduct |
0.488 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
20.5 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
1.84 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
3.98 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.371 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.0638 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Testosterone Other |
0.038 ppt | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
Auburn City of service area
This water system serves 1 community in King County, Washington. Click any city for its dedicated tap water quality page.
Find the right filter for Auburn water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.