Water Quality Report · Updated May 12, 2026

SOUTHGATE WSD

Serving 55,000 residents in CENTENNIAL, Colorado .

National rank 66th percentile
Colorado rank 52th percentile
Data confidence Medium
Quick answer

SOUTHGATE WSD delivers tap water graded C (67/100) by TapWaterSafety.org. The utility serves approximately 55,000 residents in CENTENNIAL, Colorado using surface water (purchased). 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. For questions, the utility can be reached at 303-779-0261.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
55,000
People served
1
City served
26
Contaminants detected
11
Above health guidelines
0
EPA violations (5 yr)

Is CENTENNIAL tap water safe to drink?

SOUTHGATE WSD delivers tap water that earns a grade of C (67/100) from TapWaterSafety.org — an average rating, with several contaminants above health guidelines but generally compliant with US legal limits.

The utility serves 55,000 residents in CENTENNIAL, drawing from surface water (purchased).

Public testing data identifies 11 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9)*, Total trihalomethanes (TTHMs)*, Haloacetic acids (HAA5)*, Bromodichloromethane*, Trichloroacetic acid*, Dichloroacetic acid*, Chloroform*, Dibromochloromethane*, Radium, combined (-226 and -228)*, Dibromoacetic acid*, Chromium (hexavalent)*. 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 SOUTHGATE WSD.

Haloacetic acids (HAA9)* significantly above health guideline

Moderate concern

Haloacetic acids (HAA9)* detected at 14.7 ppb, 246x above the EWG health guideline of 0.06 ppb.

Total trihalomethanes (TTHMs)* significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs)* detected at 28.9 ppb, 192x above the EWG health guideline of 0.15 ppb.

Haloacetic acids (HAA5)* significantly above health guideline

Moderate concern

Haloacetic acids (HAA5)* detected at 16.6 ppb, 166x above the EWG health guideline of 0.1 ppb.

Contact SOUTHGATE WSD

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

Recommended water filters for CENTENNIAL

Filters matched to the specific contaminants in this water supply.

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 67/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
20 / 20
Compliance History
10 / 10
Source Water Vulnerability
7 / 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
Haloacetic acids (HAA9)*
Disinfection byproduct
14.7 ppb 0.06 246× over
Total trihalomethanes (TTHMs)*
Disinfection byproduct
28.9 ppb 0.15 80.0 100 192× over
Haloacetic acids (HAA5)*
Disinfection byproduct
16.6 ppb 0.1 60.0 60 166× over
Bromodichloromethane*
Disinfection byproduct
8.02 ppb 0.06 134× over
Trichloroacetic acid*
Disinfection byproduct
6.33 ppb 0.1 63× over
Dichloroacetic acid*
Disinfection byproduct
10.1 ppb 0.2 51× over
Chloroform*
Disinfection byproduct
18.9 ppb 0.4 47× over
Dibromochloromethane*
Disinfection byproduct
1.9 ppb 0.1 19× over
Radium, combined (-226 and -228)*
Radiological
0.74 pCi/L 0.05 5.0 15× over
Dibromoacetic acid*
Disinfection byproduct
0.119 ppb 0.03 4.0× over
Chromium (hexavalent)*
Heavy metal
0.0378 ppb 0.02 1.9× over
Nitrate*
Inorganic
0.0578 ppm 0.14 10.0 11.3 11.3 10 Below guideline
Nitrate and nitrite*
Inorganic
0.0578 ppm 0.14 10.0 11.3 11.3 10 Below guideline
Molybdenum*
Other
6.86 ppb 40.0 Below guideline
Manganese*
Heavy metal
8.41 ppb 100.0 50 80 Below guideline
Barium*
Heavy metal
34.0 ppb 700.0 2000.0 1300 2000 Below guideline
Uranium*
Radiological
0.02 pCi/L 0.43 20.0 30 30 0.43 Below guideline
Cadmium*
Heavy metal
0.00122 ppb 0.04 5.0 5 3 0.04 Below guideline
Vanadium*
Other
0.264 ppb 21.0 Below guideline
Bromoform*
Disinfection byproduct
0.00622 ppb 0.5 Below guideline
Strontium*
Radiological
0.171 ppb 1500.0 Below guideline
4-Androstene-3,17-dione*
Other
0.027 ppt Below guideline
Chlorodifluoromethane*
Other
0.00808 ppb Below guideline
Chromium (total)*
Heavy metal
0.0841 ppb 100.0 Below guideline
Fluoride*
Inorganic
0.607 ppm 4.0 1.5 1.5 Below guideline
Lithium*
Other
4.08 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 (4th ed.), California OEHHA PHGs, EWG Tap Water Database.

SOUTHGATE WSD service area

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

About this water system

Public Water System ID
CO0103721
Owner type
Local government
Source water
Surface water (purchased)
Service connections
11,511
Service area
CENTENNIAL, Arapahoe County, Colorado