Water Quality in Knoxville, TN: No Violations — Grade C
Grade C · Score 66/100 · 5 water systems · Updated 2026-05-03
Knoxville's water has moderate compliance issues. Residents in affected areas should consider filtration.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Every water system supplying Knoxville, TN appears in federal EPA tracking — and all 5 carry a violation-free record with no MCL exceedances, no reportable monitoring failures, and no active enforcement actions on file in any compliance period.
Water Quality Map: Knoxville, TN
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Water Quality by ZIP Code in Knoxville
Water quality varies across Knoxville's 31 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 37917 | C | 60 | 0 | 0 | View report → |
| 37918 | C | 60 | 0 | 0 | View report → |
| 37912 | C | 65 | 0 | 0 | View report → |
| 37914 | C | 65 | 0 | 0 | View report → |
| 37919 | C | 65 | 0 | 0 | View report → |
| 37920 | C | 65 | 0 | 0 | View report → |
| 37922 | C | 65 | 0 | 0 | View report → |
| 37923 | C | 65 | 0 | 0 | View report → |
| 37931 | C | 65 | 0 | 0 | View report → |
| 37934 | C | 65 | 0 | 0 | View report → |
| 37938 | C | 65 | 0 | 0 | View report → |
| 37915 | C | 66 | 0 | 0 | View report → |
| 37927 | C | 66 | 0 | 0 | View report → |
| 37928 | C | 66 | 0 | 0 | View report → |
| 37929 | C | 66 | 0 | 0 | View report → |
Water Quality Overview
Knoxville, Tennessee receives a water quality grade of C with an overall score of 66 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
No EPA violations have been recorded for the 5 water systems serving Knoxville. This is a positive indicator, though it does not guarantee the absence of all contaminants — some substances (like PFAS) are not yet fully regulated.
What Grade C Means
A grade of C indicates moderate compliance issues. Knoxville's water systems have some violations that warrant attention. While the water may still be safe for most people, residents in affected ZIP codes should consider additional testing or filtration.
Lead Levels
The average 90th percentile lead level across Knoxville water systems is 0.0006 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 53% of homes built before 1986, Knoxville has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Radon Risk
Knoxville is in EPA Radon Zone 1 (High risk). The EPA recommends all homes in Zone 1 areas be tested for radon. Radon is the second leading cause of lung cancer after smoking.
Water Systems Serving Knoxville
Knoxville is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 573,653 people across 31 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 310 enforcement actions against water systems serving Knoxville. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Knoxville
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
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
EPA Enforcement History
The EPA and state regulators have taken 9 enforcement actions against water systems serving Knoxville. Recent actions:
| Date | Action Type |
|---|---|
| 2025-03-20 | State Informal Action |
| 2024-09-30 | State Order Extension |
| 2024-08-13 | State Informal Action |
| 2024-08-13 | State Informal Enforcement |
| 2021-12-07 | State Informal Action |
| 2021-11-30 | State Order Extension |
| 2021-08-09 | State Order Extension |
| 2021-06-30 | State Order Extension |
| 2021-05-18 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-03-20.
Knoxville vs. Nearby Tennessee Cities
How Knoxville's water quality compares to similar cities in Tennessee:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Knoxville | C | 0 | 5 | 573,653 |
| Arlington | C | 0 | 1 | 659,500 |
| Brunswick | B | 0 | 1 | 659,500 |
| Cordova | C | 0 | 1 | 659,500 |
Recommended Water Filters for Knoxville
Based on contaminants detected in Knoxville's water supply, these filter types are recommended:
Granular Activated Carbon (GAC, under-sink or whole-house)
- Removes: Haloacetic Acid HAA5
- Effectiveness: 60-80%
- Cost range: $100–$600
- Certification: NSF/ANSI 53
- Recommended products:
Water Quality by ZIP Code in Knoxville
Water quality varies across Knoxville's ZIP codes. The table below shows the worst-scoring and best-scoring areas:
| ZIP Code | Score | Grade | Violations | Health-Based |
|---|---|---|---|---|
| 37917 | 60 | C | 0 | 0 |
| 37918 | 60 | C | 0 | 0 |
| 37912 | 65 | C | 0 | 0 |
| 37914 | 65 | C | 0 | 0 |
| 37919 | 65 | C | 0 | 0 |
| 37920 | 65 | C | 0 | 0 |
| 37922 | 65 | C | 0 | 0 |
| 37923 | 65 | C | 0 | 0 |
| 37931 | 65 | C | 0 | 0 |
| 37934 | 65 | C | 0 | 0 |
| 37932 | 70 | B | 0 | 0 |
| 37924 | 70 | B | 0 | 0 |
| 37921 | 70 | B | 0 | 0 |
| 37916 | 70 | B | 0 | 0 |
| 37909 | 70 | B | 0 | 0 |
Common Questions About Knoxville Water
These are the most common questions residents search for about water quality in Knoxville, Tennessee:
Is Knoxville water hard or soft? Water hardness varies by source. Knoxville's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Knoxville tap water? Knoxville's water receives a grade of C (66/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Knoxville? Based on detected contaminants, a granular activated carbon (gac, under-sink or whole-house) filter is most recommended. See our Water Filter Matcher for personalized recommendations.
Knoxville vs. Tennessee Average
Understanding how Knoxville compares to the broader Tennessee 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 Knoxville.
ZIP Codes in Knoxville
Knoxville spans 31 ZIP codes. Each ZIP code has its own water quality profile based on the specific water system serving that area. 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
Updated daily.