Tap Water Quality Report
Tap water quality in WEST ALLIS, Wisconsin
Tap water in WEST ALLIS, Wisconsin receives a grade of D (66/100) from TapWaterSafety.org. It's served by WEST ALLIS WATERWORKS. The most significant water quality concerns are: PFAS contamination; Total PFOS and PFOA* significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in WEST ALLIS's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving WEST ALLIS.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS)*, Perfluorooctanoic acid (PFOA)* detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Total PFOS and PFOA* significantly above health guideline
Moderate concernTotal PFOS and PFOA* detected at 3.4 ppt, 486x above the EWG health guideline of 0.007 ppt.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 6.6 ppb, 110x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 9.86 ppb, 66x above the EWG health guideline of 0.15 ppb.
EPA compliance record
Official U.S. EPA records for WEST ALLIS WATERWORKS (system ID WI2410595) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for WEST ALLIS
Filters matched to the specific contaminants in WEST ALLIS's water supply.
Filter certified for PFOA/PFOS (NSF/ANSI 53 or 58)
$180-$750Reverse osmosis and some carbon block filters reduce PFAS. Look for certification to NSF/ANSI 53 or 58 for PFOA/PFOS.
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.
All contaminants detected in WEST ALLIS's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. 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 |
|---|---|---|---|---|---|---|---|---|
| Total PFOS and PFOA* PFAS |
3.4 ppt | 0.007 | — | 100 | 100 | 0.007 | — | 486× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
6.6 ppb | 0.06 | — | — | — | — | — | 110× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
9.86 ppb | 0.15 | 80.0 | 100 | — | — | — | 66× over |
| Bromodichloromethane Disinfection byproduct |
3.42 ppb | 0.06 | — | — | — | — | — | 57× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
2.87 ppb | 0.1 | 60.0 | 60 | — | — | — | 29× over |
| Dibromochloromethane Disinfection byproduct |
2.11 ppb | 0.1 | — | — | — | — | — | 21× over |
| Bromate* Disinfection byproduct |
1.72 ppb | 0.1 | 10.0 | 10 | 10 | 0.1 | — | 17× over |
| Dibromoacetic acid Disinfection byproduct |
0.463 ppb | 0.03 | — | — | — | — | — | 15× over |
| Chloroform Disinfection byproduct |
3.99 ppb | 0.4 | — | — | — | — | — | 10× over |
| Chromium (hexavalent) Heavy metal |
0.204 ppb | 0.02 | — | — | — | — | — | 10× over |
| Dichloroacetic acid Disinfection byproduct |
1.58 ppb | 0.2 | — | — | — | — | — | 7.9× over |
| Trichloroacetic acid Disinfection byproduct |
0.756 ppb | 0.1 | — | — | — | — | — | 7.6× over |
| Perfluorooctanoic acid (PFOA)* PFAS |
0.675 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 7.5× over |
| Perfluorooctane sulfonate (PFOS)* PFAS |
1.03 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 3.4× over |
| Nitrate* Inorganic |
0.355 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.5× over |
| Nitrate and nitrite* Inorganic |
0.317 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.3× over |
| Bromoform Disinfection byproduct |
0.335 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Chlorate Disinfection byproduct |
49.2 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Atrazine* Pesticide/Herbicide |
0.0195 ppb | 0.1 | 3.0 | 0.1 | 100 | 0.15 | — | Below guideline |
| Antimony* Heavy metal |
0.17 ppb | 1.0 | 6.0 | 10 | 20 | 1 | — | Below guideline |
| Barium* Heavy metal |
19.8 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Molybdenum Other |
0.633 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
0.272 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
0.232 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.0523 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0196 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.118 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Chromium (total)* Heavy metal |
0.795 ppb | — | 100.0 | — | — | — | — | Below guideline |
| Fluoride* Inorganic |
0.597 ppm | — | 4.0 | 1.5 | 1.5 | — | — | 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, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from WEST ALLIS WATERWORKS.