Is Duncan Tap Water Safe to Drink?

Can You Drink Tap Water in Duncan?

Yes, Duncan's tap water is generally considered safe to drink as Duncan has no active health based violations of the Safe Drinking Water Act (SDWA) that we are aware of. Other factors such as lead piping in a home, or low levels of pollutants on immunocompromised individuals, should also be considered, however. To find more recent info we might have, you can check out our boil water notice page or the city's water provider website.

According the EPA’s ECHO database, from April 30, 2019 to June 30, 2022, Duncan's water utility, Duncan Public Utilities Authority, had 13 health-based violations of the Safe Drinking Water Act. For more details on the violations, please see our violation history section below. The last violation for Duncan was resolved on March 31, 2020. This assessment is based on the Duncan Public Utilities Authority water system, other water systems in the city may have different results.

While tap water that meets the EPA health guidelines generally won’t make you sick to your stomach, it can still contain regulated and unregulated contaminants present in trace amounts that could potentially cause health issues over the long-run. These trace contaminants may also impact immunocompromised and vulnerable individuals.

The EPA is reviewing if it’s current regulations around pollutant levels in tap water are strict enough, and the health dangers posed by unregulated pollutants, like PFAS.

Duncan Tap Water Safe Drinking Water Act Violation History - Prior 10 Years

Below is a ten year history of violations for the water system named Duncan Public Utilities Authority for Duncan in Oklahoma. For more details please see the "What do these Violations Mean?" section below.

From April 1, 2020 to June 30, 2020, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From Jan. 1, 2020 to March 31, 2020, Duncan had 3 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, TTHM, TTHM.

From Jan. 1, 2020 to March 31, 2020, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Treatment Technique Violation, more specifically, the violation code was Treatment Technique Precursor Removal which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 1 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: CARBON, TOTAL.

From Oct. 1, 2019 to Dec. 31, 2019, Duncan had 4 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, TTHM, TTHM, TTHM.

From July 1, 2019 to Sept. 30, 2019, Duncan had 4 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, TTHM, TTHM, TTHM.

From April 1, 2019 to June 30, 2019, Duncan had 4 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, TTHM, TTHM, TTHM.

From Jan. 1, 2019 to March 31, 2019, Duncan had 4 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, TTHM, TTHM, TTHM.

From Oct. 1, 2018 to Dec. 31, 2018, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From July 1, 2018 to Sept. 30, 2018, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From April 1, 2018 to June 30, 2018, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From Jan. 1, 2018 to March 31, 2018, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From Oct. 1, 2017 to Dec. 31, 2017, Duncan had 1 non-health based Safe Drinking Water Act violation with the violation category being Monitoring and Reporting, more specifically, the violation code was Monitoring and Reporting (DBP) which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 1 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: Chloramine.

From Oct. 1, 2017 to Dec. 31, 2017, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From July 1, 2017 to Sept. 30, 2017, Duncan had 2 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: Total Haloacetic Acids (HAA5), TTHM.

From Feb. 1, 2017 to April 30, 2017, Duncan had 2 non-health based Safe Drinking Water Act violations with the violation category being Monitoring and Reporting, more specifically, the violation code was Monitoring and Reporting (DBP) which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: Total Haloacetic Acids (HAA5), TTHM.

From Jan. 1, 2017 to March 31, 2017, Duncan had 2 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: Total Haloacetic Acids (HAA5), TTHM.

From Dec. 1, 2016 to Dec. 31, 2016, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Treatment Technique Violation, more specifically, the violation code was Single Turbidity Exceed (Enhanced SWTR) which falls into the Microbials rule code group, and the Surface Water Treatment Rules rule code family for the following contaminant code: Interim Enhanced Surface Water Treatment Rule.

From Nov. 1, 2016 to Jan. 31, 2017, Duncan had 2 non-health based Safe Drinking Water Act violations with the violation category being Monitoring and Reporting, more specifically, the violation code was Monitoring and Reporting (DBP) which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, Total Haloacetic Acids (HAA5).

From Oct. 1, 2016 to Dec. 31, 2016, Duncan had 2 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: Total Haloacetic Acids (HAA5), TTHM.

From July 1, 2016 to Sept. 30, 2016, Duncan had 2 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: Total Haloacetic Acids (HAA5), TTHM.

From April 1, 2016 to June 30, 2016, Duncan had 2 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, Total Haloacetic Acids (HAA5).

From Jan. 1, 2016 to March 31, 2016, Duncan had 2 health-based Safe Drinking Water Act violations with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, Total Haloacetic Acids (HAA5).

From Oct. 1, 2015 to Dec. 31, 2015, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From July 1, 2015 to Sept. 30, 2015, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From April 1, 2015 to June 30, 2015, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From April 1, 2015 to June 30, 2015, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Treatment Technique Violation, more specifically, the violation code was Treatment Technique Precursor Removal which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 1 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: CARBON, TOTAL.

From Jan. 1, 2015 to March 31, 2015, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From Jan. 1, 2015 to March 31, 2015, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Treatment Technique Violation, more specifically, the violation code was Treatment Technique Precursor Removal which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 1 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: CARBON, TOTAL.

From Oct. 1, 2014 to Dec. 31, 2014, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From July 1, 2014 to Sept. 30, 2014, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From April 1, 2014 to June 30, 2014, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From Jan. 1, 2014 to March 31, 2014, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From Nov. 1, 2013 to Jan. 31, 2014, Duncan had 2 non-health based Safe Drinking Water Act violations with the violation category being Monitoring and Reporting, more specifically, the violation code was Monitoring and Reporting (DBP) which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, Total Haloacetic Acids (HAA5).

From Oct. 1, 2013 to Dec. 31, 2013, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 2 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From Aug. 1, 2013 to Oct. 31, 2013, Duncan had 2 non-health based Safe Drinking Water Act violations with the violation category being Monitoring and Reporting, more specifically, the violation code was Monitoring and Reporting (DBP) which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 1 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant codes: TTHM, Total Haloacetic Acids (HAA5).

From April 1, 2012 to June 30, 2012, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 1 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

From Jan. 1, 2012 to March 31, 2012, Duncan had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Average which falls into the Disinfectants and Disinfection Byproducts Rule rule code group, and the Stage 1 Disinfectants and Disinfection Byproducts Rule rule code family for the following contaminant code: TTHM.

Is there Lead in Duncan Water?

Based on the EPA’s ECHO Database, 90% of the samples taken from the Duncan water system, Duncan Public Utilities Authority, between sample start date and sample end date, were at or below, 0.0 mg/L of lead in Duncan water. This is 0% of the 0.015 mg/L action level. This means 10% of the samples taken from Duncan contained more lead.

While Duncan water testing may have found 0.0 mg/L of lead in its water, that does not mean your water source has the same amount. The amount of lead in water in a city can vary greatly from neighborhood to neighborhood, or even building to building. Many buildings, particularly older ones, have lead pipes or service lines which can be a source of contamination. To find out if your home has lead, we recommend getting you water tested.

No amount of lead in water is healthy, only less dangerous. As lead accumulates in our bodies over time, even exposure to relatively small amounts can have negative health effects. For more information, please check out our Lead FAQ page.

Are there PFAS in Duncan Tap Water?

Currently, testing tap water for PFAS isn’t mandated on a national level. We do have a list of military bases where there have been suspected or confirmed leaks. There appears to be at least one military base - Fort Sill - near Duncan with suspected leaks.

With many potential sources of PFAS in tap water across the US, the best information we currently have about which cities have PFAS in their water is this ewg map, which you can check to see if Duncan has been evaluated for yet.

Our stance is better safe than sorry, and that it makes sense to try to purify the tap water just in case.

Duncan SDWA Violation History Table - Prior 10 Years

What do these Violations Mean?

Safe Drinking Water Act Violations categories split into two groups, health based, and non-health based. Generally, health based violations are more serious, though non-health based violations can also be cause for concern.

Health Based Violations

1. Maximum contaminant levels (MCLs) - maximum allowed contaminant level was exceeded.
2. Maximum residual disinfectant levels (MRDLs) - maximum allowed disinfectant level was exceeded.
3. Other violations (Other) - the exact required process to reduce the amounts of contaminants in drinking water was not followed.

Non-Health Based Violations

1. Monitoring and reporting violations (MR, MON) - failure to conduct the required regular monitoring of drinking water quality, and/or to submit monitoring results on time.
2. Public notice violations (Other) - failure to immediately alert consumers if there is a serious problem with their drinking water that may pose a risk to public health.
3. Other violations (Other) - miscellaneous violations, such as failure to issue annual consumer confidence reports or maintain required records.

SDWA Table Key

For more clarification please visit the EPA's data dictionary.