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These Oklahoma cities have the cleanest, safest drinking water based on EPA contaminant data, compliance records, and infrastructure quality. Residents in these areas enjoy some of the best tap water in the state.
The Oklahoma cities with the best tap water on EPA record are Tulsa (A, 100/100); Oklahoma City (A, 98/100). Tulsa leads the state at 100/100 (Grade A), scored on EPA contaminant levels, five-year violation history, and lead results. See the full top 20 below.
Tulsa has the best water quality of any graded Oklahoma city, scoring 100/100 (Grade A) on EPA data. Its rating reflects low detected contaminant levels, a clean five-year violation record, and low Lead and Copper Rule 90th-percentile results.
Each city starts at 100 and loses points for real EPA findings about its water system: health-based violations in the last five years (SDWIS), its latest Lead and Copper Rule 90th-percentile result, PFAS detected in EPA UCMR5 monitoring, and 2012–2019 compliance samples near or above a limit. Letters follow fixed bands: A ≥90, B ≥80, C ≥70, D ≥60, F below 60. Cities we cannot match to an EPA system are not graded.
Even in top-rated cities, a filter can help with chlorine taste, lead added by older home plumbing, or extra protection for infants and immunocompromised residents. Match the filter to any contaminant still flagged for your city — our water filter guide pairs common contaminants with proven filtration methods.
The cities listed below meet or exceed all EPA water quality requirements and demonstrate consistently excellent performance in protecting public health through clean drinking water.
How the top 20 cities in Oklahoma are distributed by water quality grade
Click any city to see detailed water quality report including specific contaminants, test results, and filter recommendations.
| Rank | City | Score | Grade | Population Served | Details |
|---|---|---|---|---|---|
1 | Tulsa | 100/100 | A | 413,000 | View Report → |
2 | Oklahoma City | 98/100 | A | 644,000 | View Report → |
Cities with excellent water quality typically share several common characteristics that contribute to their high scores:
Clean aquifers, reservoirs, or rivers with minimal upstream contamination from agriculture or industry.
State-of-the-art water treatment plants with advanced filtration and disinfection technology.
Regular pipe replacement, system upgrades, and proactive maintenance to prevent contamination.
Few or no violations, with consistent adherence to Safe Drinking Water Act requirements.
Even in cities with excellent water quality, some residents choose to use water filters for:
Complete water quality rankings for every city
View water quality by county in Oklahoma
Contaminants found in Oklahoma water
Top 50 cities nationwide
#1 city from each state
Side-by-side water quality comparison