Water Quality in Stillwater, OK: 32 Violations - Grade N/A
6 water systems · 4 directly mapped ZIP records
Available EPA records report 32 violations across 4 directly mapped ZIP records with known counts for Stillwater. This is compliance evidence, not a property-level tap-water verdict.
Data: EPA Safe Drinking Water Information System (SDWIS)
Water Quality by ZIP Code in Stillwater
This table shows typed EPA water evidence only. Missing violation counts are displayed as N/A, not zero.
| ZIP Code | Violations | Health | |
|---|---|---|---|
| 74074 | 32 | 29 | View report → |
| 74075 | 32 | 29 | View report → |
| 74077 | 10 | 9 | View report → |
| 74078 | 10 | 9 | View report → |
Violation Trend
EPA violations recorded for water systems serving Stillwater.
| Year | Total violations | Health-based |
|---|---|---|
| 2021 | 5 | 5 |
| 2022 | 12 | 12 |
| 2023 | 8 | 8 |
| 2024 | 1 | 1 |
| 2025 | 8 | 8 |
Water Quality Overview
Stillwater, Oklahoma has directly mapped EPA water-system data for 4 ZIP codes. This page reports typed compliance facts and does not relabel the multi-source Home Safety Score as a drinking-water grade.
The available EPA records report 32 violations, including 29 health-based violations across 4 directly mapped ZIP records with reported counts.
Lead Levels
The average 90th percentile lead level across Stillwater water systems is 0.0030 mg/L - within EPA limits. No exceedances appear among the 4 ZIP records with known lead status.
Water Systems Serving Stillwater
Stillwater is served by 6 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 60,676 people across 5 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 40 enforcement actions against water systems serving Stillwater. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Stillwater
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels and violation history
Request your CCR - your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test - certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration - NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories - monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in Stillwater Water Systems
The following contaminants have been detected or caused violations across Stillwater's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 0.06 mg/L | 36 | 4 | Yes |
| Chlorite | Disinfection Byproducts | 1 mg/L | 16 | 4 | Yes |
| E. coli | Microbiological | N/A | 12 | 4 | Yes |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 0.08 mg/L | 10 | 2 | Yes |
| Arsenic | Inorganic | 0.01 mg/L | 6 | 2 | Yes |
| Stage 2 DBP Rule | Treatment Technique | N/A | 4 | 2 | Yes |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
Violation Trend Over Time
Year-by-year EPA violations recorded for water systems serving Stillwater:
| Year | Total Violations | Health-Based |
|---|---|---|
| 2021 | 5 | 5 |
| 2022 | 12 | 12 |
| 2023 | 8 | 8 |
| 2024 | 1 | 1 |
| 2025 | 8 | 8 |
Violations have increased from 5 in 2021 to 8 in 2025. This trend warrants monitoring.
EPA Enforcement History
The EPA and state regulators have taken 13 enforcement actions against water systems serving Stillwater. Recent actions:
| Date | Action Type |
|---|---|
| 2026-02-19 | State Informal Action |
| 2026-02-19 | State Informal Enforcement |
| 2025-12-10 | State Order Extension |
| 2025-11-19 | State Informal Enforcement |
| 2025-11-19 | State Filed Suit |
| 2025-10-06 | State Informal Action |
| 2025-09-04 | State Informal Enforcement |
| 2025-09-04 | State Filed Suit |
| 2025-07-29 | State Informal Action |
| 2025-07-15 | State Order Extension |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2026-02-19.
Stillwater vs. Nearby Oklahoma Cities
How Stillwater's water quality compares to similar cities in Oklahoma:
| City | Direct EPA ZIPs | Violations | Systems | Population |
|---|---|---|---|---|
| Stillwater | 4 | 32 | 6 | 60,676 |
| Enid | 2 | 96 | 6 | 55,379 |
| Owasso | 1 | 35 | 5 | 49,895 |
| Claremore | 2 | 66 | 7 | 49,534 |
Water Quality by ZIP Code in Stillwater
EPA coverage and recorded violations can differ across Stillwater's ZIP codes. Missing counts are shown as unavailable, not zero:
Common Questions About Stillwater Water
These are the most common questions residents search for about water quality in Stillwater, Oklahoma:
Is Stillwater water hard or soft? Water hardness varies by source. Stillwater's 6 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Stillwater tap water? City-level EPA records cannot determine safety at a specific tap. The measured subset contains 29 health-based violations; check the affected utility record and consider certified testing.
What is the best water filter for Stillwater? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Stillwater vs. Oklahoma Average
Understanding how Stillwater compares to the broader Oklahoma average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below - water quality can vary significantly even within Stillwater.
ZIP Codes in Stillwater
Stillwater spans 5 ZIP codes. EPA water-system coverage is available for 4 directly mapped ZIP codes. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Source reporting periods vary. See each cited source for its publication schedule.