EPA data as of Oct 2026 · page updated 2026-10-29

Duncan Public Utilities Authority

Duncan Public Utilities Authority (EPA ID OK1010809) in Duncan, OK supplies surface water (rivers, lakes) to about 23,000 people: 44 violations since 2016, latest lead result 0 ppb, PFAS 4 detected.

Service area

EPA service-area boundary (state-supplied or EPA-modeled)
Water utility service area PFOA/PFOS ≥ 4 ppt Lead > 15 ppb 5+ violations Superfund site (active) proposed cleaned up Circles: other water systems flagged nearby; size = people served. Tap any symbol for details.

System facts

People served23,000
Connections10,938
Sourcesurface water (rivers, lakes)
WholesalerNo

Health-based violations

Contaminant or ruleHealth-based violations since 2016
TTHM32
Total Haloacetic Acids (Haa5)6
Carbon, Total5
Interim Enhanced Surface Water Treatment Rule1

A health-based violation means a contaminant exceeded its legal limit (MCL) or a required treatment technique was not met, as reported by the state to EPA’s SDWIS. All are listed as resolved or archived; the latest began Oct 2024.

Lead

Jan 20220 ppb
Jan 20190 ppb
Jan 20160 ppb
Jan 20130 ppb
Jan 20100 ppb
Jan 20070 ppb
Jan 20040 ppb
Jan 20010 ppb

90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.

PFAS

CompoundHighest resultSamples with detectionEPA limit
PFBA7.5 ppt7 of 8—
PFPeA3.8 ppt5 of 8—
PFHpA3.4 ppt3 of 8—
PFHxA3.3 ppt2 of 8—
PFHxSnot detected0 of 8—
HFPO-DA (GenX)not detected0 of 8—
PFBSnot detected0 of 8—
PFDAnot detected0 of 8—
PFOAnot detected0 of 84 ppt MCL
PFOSnot detected0 of 84 ppt MCL
PFNAnot detected0 of 8—

EPA Fifth Unregulated Contaminant Monitoring Rule (UCMR 5), samples 2023–2025; ppt = parts per trillion (ng/L). The 4.0 ppt maximum contaminant levels for PFOA and PFOS were set by EPA in 2024; water systems have until the end of the decade to comply.

ZIP codes served

ZIP codes whose center lies in this system’s service area or that the state lists for it.

What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.

Questions

Has Duncan Public Utilities Authority had drinking water violations?

Health-based violations since 2016: TTHM, Total Haloacetic Acids (Haa5), Carbon, Total. All are listed as resolved.

What is the lead level in Duncan Public Utilities Authority water?

The latest 90th-percentile lead result (Jan 2022) was 0 ppb. EPA’s action level is 15 ppb (10 ppb from 2027).

Does Duncan Public Utilities Authority have PFAS in its water?

PFAS were detected, with PFOA and PFOS below 4.0 ppt (highest not detected).