QC Water Quality Rankings
1 cities ranked · Data from EPA SDWIS
91.6
State avg score
1
Cities ranked
100%
A or B grade
0%
D or F grade
1
Health violations
0
PFAS detected
Analysis
QC water quality overview
QC's drinking water quality is excellent overall, with a state average score of 91.6 out of 100 — 17.4 points above the national average of 74.2. The median city score is 91.6, reflecting how water quality is distributed across the state's 1 ranked cities. 100% of QC cities earned an A or B grade, indicating broadly strong water quality infrastructure. Only 0 cities received a failing grade. 1 city has recorded health-based violations with the EPA — meaning contaminant levels exceeded safe limits or required testing was missed. Use the table below to find your city's specific record.
Grade Distribution
How QC cities scored
A
1
100%
Excellent
B
0
0%
Good
C
0
0%
Fair
D
0
0%
Poor
F
0
0%
Failing
Score Distribution
Score distribution by range
1 1 0
0–9
10–19
20–29
30–39
40–49
50–59
60–69
70–79
80–89
90–100
Comparison
State vs national average
▲ 17.4 pts above national average
City Map
Water quality across QC
Each dot is a city, colored by grade. Size reflects population served. Click any city to view its full report.
Full Rankings
All 1 cities in QC
| # | City | Grade | Score | Score | Population | Violations | Issues |
|---|---|---|---|---|---|---|---|
| 1 | Derby | A | 91.6 | 897 | 11 | Health Unresolved |