Water Quality Report · Updated May 12, 2026

DUBUQUE WATER WORKS

Serving 59,667 residents in DUBUQUE, Iowa .

National rank 18th percentile
Iowa rank 17th percentile
Data confidence Medium
Quick answer

DUBUQUE WATER WORKS delivers tap water graded F (54/100) by TapWaterSafety.org. The utility serves approximately 59,667 residents in DUBUQUE, Iowa using groundwater. The most significant water quality concerns are: PFAS contamination; Total PFOS and PFOA significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline. For questions, the utility can be reached at 563-589-4291.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
59,667
People served
1
City served
23
Contaminants detected
14
Above health guidelines
0
EPA violations (5 yr)

Is DUBUQUE tap water safe to drink?

DUBUQUE WATER WORKS delivers tap water that earns a grade of F (54/100) from TapWaterSafety.org — a poor rating, with significant contamination concerns and/or recent violations.

The utility serves 59,667 residents in DUBUQUE, drawing from groundwater.

Public testing data identifies 14 contaminants in this water above EWG's health-based guidelines, including: Total PFOS and PFOA, Total trihalomethanes (TTHMs), Haloacetic acids (HAA9), Bromodichloromethane, Chloroform, Haloacetic acids (HAA5), Dibromochloromethane, Perfluorooctanoic acid (PFOA), Dichloroacetic acid, Trichloroacetic acid, Chromium (hexavalent), Dibromoacetic acid, Perfluorooctane sulfonate (PFOS), Nitrate. 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.

Top concerns in this water

Based on the most recent EPA and EWG data, these are the most significant water quality issues for DUBUQUE WATER WORKS.

PFAS contamination

Severe concern

Perfluorooctane 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 concern

Total PFOS and PFOA detected at 6.63 ppt, 946x above the EWG health guideline of 0.007 ppt.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 47.8 ppb, 319x above the EWG health guideline of 0.15 ppb.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 14.4 ppb, 240x above the EWG health guideline of 0.06 ppb.

Contact DUBUQUE WATER WORKS

Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.

Recommended water filters for DUBUQUE

Filters matched to the specific contaminants in this water supply.

Reverse Osmosis or NSF P473 certified carbon

$80-$750

Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →
Clearly Filtered Pitcher Filter
$80-$95 NSF 42, 53, 401, P473
Editorial pick · affiliate link coming soon

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 54/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
6 / 20
Compliance History
10 / 10
Source Water Vulnerability
8 / 10

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
Total PFOS and PFOA
PFAS
6.63 ppt 0.007 100 100 0.007 946× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
47.8 ppb 0.15 80.0 100 319× over
Haloacetic acids (HAA9)
Disinfection byproduct
14.4 ppb 0.06 240× over
Bromodichloromethane
Disinfection byproduct
10.5 ppb 0.06 176× over
Chloroform
Disinfection byproduct
32.5 ppb 0.4 81× over
Haloacetic acids (HAA5)
Disinfection byproduct
7.65 ppb 0.1 60.0 60 77× over
Dibromochloromethane
Disinfection byproduct
4.59 ppb 0.1 46× over
Perfluorooctanoic acid (PFOA)
PFAS
3.07 ppt 0.09 4.0 100 100 0.007 34× over
Dichloroacetic acid
Disinfection byproduct
5.71 ppb 0.2 29× over
Trichloroacetic acid
Disinfection byproduct
2.13 ppb 0.1 21× over
Chromium (hexavalent)
Heavy metal
0.349 ppb 0.02 17× over
Dibromoacetic acid
Disinfection byproduct
0.346 ppb 0.03 12× over
Perfluorooctane sulfonate (PFOS)
PFAS
2.82 ppt 0.3 4.0 100 100 1 9.4× over
Nitrate
Inorganic
0.653 ppm 0.14 10.0 11.3 11.3 10 4.7× over
Chlorate
Disinfection byproduct
113.3 ppb 210.0 Below guideline
1,4-Dioxane
Semi-volatile organic compound
0.164 ppb 0.35 50 1 Below guideline
Bromoform
Disinfection byproduct
0.223 ppb 0.5 Below guideline
Manganese
Heavy metal
1.5 ppb 100.0 50 80 Below guideline
Perfluorobutanoic Acid (PFBA)
PFAS
10.6 ppt 1000.0 Below guideline
Vanadium
Other
0.15 ppb 21.0 Below guideline
Strontium
Radiological
0.0394 ppb 1500.0 Below guideline
4-Androstene-3,17-dione
Other
0.26 ppt Below guideline
Fluoride
Inorganic
0.62 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 (4th ed.), California OEHHA PHGs, EWG Tap Water Database.

DUBUQUE WATER WORKS service area

This water system serves 1 community in Dubuque County, Iowa. Click any city for its dedicated tap water quality page.

About this water system

Public Water System ID
IA3126052
Owner type
Local government
Source water
Groundwater
Service connections
23,954
Service area
DUBUQUE, Dubuque County, Iowa