D38/100
Guymon Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 11,442 residents · Oklahoma
What's In Guymon's Tap Water?
66
Contaminants Tested
0
Exceed EPA Limits
1
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
1,4-dioxane | 0.550 µg/L | — | Above Goal |
EPA Violation History
6
Violations (last 5yr)
0
Unresolved
1
Health-Related
TIER 1 — URGENTResolved
Exceeded the Maximum Contaminant Level (single sample)
When: January 1, 2025 – September 3, 2025Enforcement: Formal — state order issued
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2023 – December 31, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2023 – December 31, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2023 – December 31, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2023 – December 31, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2023 – December 31, 2023Enforcement: Resolving — corrective action underway
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
GUYMON
Population Served
11,442
Water Source
Groundwater
System ID
OK2007003
Frequently Asked Questions About Guymon Water
Is Guymon tap water safe to drink?
Guymon, Oklahoma tap water receives a grade of D (38/100), which is considered poor. 0 contaminant(s) exceed EPA maximum contaminant levels and 19 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Guymon's water?
Of the 66 contaminants tested in Guymon's water supply, the most notable include 1,4-dioxane. No contaminants exceed EPA legal limits. 1 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Guymon have any water quality violations?
Yes, Guymon has 19 EPA violation(s) on record, with the most recent in 2025. Violation types include MCL, MR, MON. 10 of these are health-based violations, which are the most serious category.
Do I need a water filter in Guymon?
Guymon water meets EPA standards, so a filter is not strictly necessary. However, some residents prefer the added security of a water filter. EPA health goals (MCLGs) are stricter than legal limits and are set at levels with zero expected health risk. 1 contaminant(s) exceed these stricter goals.
Where does Guymon's tap water come from?
Guymon's drinking water is sourced from groundwater and supplied by GUYMON. The system serves approximately 11,442 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Guymon's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Guymon's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Guymon's water compare to other cities in Oklahoma?
Guymon's water quality score of 38/100 earns a grade of D, which is considered poor. This is a concerning score that suggests significant water quality issues. Visit our Oklahoma state page to see how all cities in the state compare.
What should I do if I'm concerned about Guymon's water quality?
If you have concerns about Guymon's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (GUYMON) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.