Tap Water Quality Report
Tap water quality in GREELEY, Colorado
Tap water in GREELEY, Colorado receives a grade of C (74/100) from TapWaterSafety.org. It's served by GREELEY CITY OF. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in GREELEY's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving GREELEY.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 30.6 ppb, 509x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 45.8 ppb, 305x above the EWG health guideline of 0.15 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 23.5 ppb, 235x above the EWG health guideline of 0.1 ppb.
EPA compliance record
Official U.S. EPA records for GREELEY CITY OF (system ID CO0162321) for the last 3 years. Checked 2026-10-07.
| Rule | Type | Since | Status |
|---|---|---|---|
| Stage 1 Disinfectants and Disinfection Byproducts Rule | Missed testing or reporting | 06/01/2023 | Resolved |
| Lead and Copper Rule | Missed testing or reporting | 10/01/2024 | Resolved |
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 GREELEY
Filters matched to the specific contaminants in GREELEY's water supply.
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 GREELEY'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 |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA9) Disinfection byproduct |
30.6 ppb | 0.06 | — | — | — | — | — | 509× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
45.8 ppb | 0.15 | 80.0 | 100 | — | — | — | 305× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
23.5 ppb | 0.1 | 60.0 | 60 | — | — | — | 235× over |
| Bromodichloromethane Disinfection byproduct |
8.08 ppb | 0.06 | — | — | — | — | — | 135× over |
| Chloroform Disinfection byproduct |
36.3 ppb | 0.4 | — | — | — | — | — | 91× over |
| Trichloroacetic acid Disinfection byproduct |
8.81 ppb | 0.1 | — | — | — | — | — | 88× over |
| Dichloroacetic acid Disinfection byproduct |
14.2 ppb | 0.2 | — | — | — | — | — | 71× over |
| Dibromochloromethane Disinfection byproduct |
1.43 ppb | 0.1 | — | — | — | — | — | 14× over |
| Chlorite Disinfection byproduct |
271.6 ppb | 50.0 | 1000.0 | — | — | — | — | 5.4× over |
| Dibromoacetic acid Disinfection byproduct |
0.0471 ppb | 0.03 | — | — | — | — | — | 1.6× over |
| Chromium (hexavalent) Heavy metal |
0.0179 ppb | 0.02 | — | — | — | — | — | Below guideline |
| Nitrate Inorganic |
0.0988 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | Below guideline |
| Benzene Volatile organic compound |
0.08 ppb | 0.15 | 5.0 | 1 | 10 | 0.15 | — | Below guideline |
| Chlorate Disinfection byproduct |
48.7 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
46.8 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Selenium Heavy metal |
1.0 ppb | 30.0 | 50.0 | 20 | 40 | 30 | — | Below guideline |
| Bromoform Disinfection byproduct |
0.0143 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
2.34 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Molybdenum Other |
0.65 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
0.314 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.356 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0166 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.235 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.317 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
9.79 ppb | — | — | — | — | — | — | 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 GREELEY CITY OF.