Water Quality in Largo, FL: 54 Violations — Grade C
Grade C · Score 60/100 · 4 water systems · Updated 2026-05-03
Largo'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
The compliance history for Largo, FL includes 54 water violations on file with the EPA — a federal tally that spans health-based exceedances, monitoring failures, and enforcement actions logged under the Safe Drinking Water Act.
Water Quality Map: Largo, FL
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Water Quality by ZIP Code in Largo
Water quality varies across Largo's 6 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 33770 | C | 66 | 9 | 0 | View report → |
| 33774 | C | 66 | 9 | 0 | View report → |
| 33771 | B | 71 | 9 | 0 | View report → |
| 33773 | B | 71 | 9 | 0 | View report → |
| 33778 | B | 76 | 9 | 0 | View report → |
| 33779 | B | 83 | 9 | 0 | View report → |
Water Quality Overview
Largo, Florida receives a water quality grade of C with an overall score of 60 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 4 water systems serving Largo have accumulated 54 EPA violations (all monitoring/reporting type). These violations are tracked across 6 ZIP codes serving approximately 506,558 people.
What Grade C Means
A grade of C indicates moderate compliance issues. Largo'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 Largo water systems is 0.0008 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 75% of homes built before 1986, Largo 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
Largo is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Largo
Largo is served by 4 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 506,558 people across 6 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 12 enforcement actions against water systems serving Largo. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Largo
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
Contaminants Detected in Largo Water Systems
The following contaminants have been detected or caused violations across Largo's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 0.06 mg/L | 18 | 6 | No |
| Stage 1 DBP Rule | Treatment Technique | N/A | 6 | 6 | No |
| Lead | Inorganic | 0.015 mg/L | 6 | 6 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
EPA Enforcement History
The EPA and state regulators have taken 2 enforcement actions against water systems serving Largo. Recent actions:
| Date | Action Type |
|---|---|
| 2023-09-22 | State Order Extension |
| 2021-12-01 | State Order Extension |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2023-09-22.
Largo vs. Nearby Florida Cities
How Largo's water quality compares to similar cities in Florida:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Largo | C | 54 | 4 | 506,558 |
| Bay Pines | C | 0 | 1 | 506,353 |
| Belleair Beach | D | 0 | 1 | 506,353 |
| Clearwater Beach | D | 0 | 1 | 506,353 |
Recommended Water Filters for Largo
Based on contaminants detected in Largo's water supply, these filter types are recommended:
UV Disinfection System (POE or POU)
- Removes: Total Coliform Bacteria
- Effectiveness: 99.99%
- Cost range: $100–$700
- Certification: NSF/ANSI 55
- Recommended products:
- Viqua VH200
- HQUA UV System
- Waterdrop G3P800
Reverse Osmosis (under-sink)
- Removes: Arsenic, Barium, Chromium
- Effectiveness: 90-99%
- Cost range: $150–$500
- Certification: NSF/ANSI 58
- Recommended products:
- Waterdrop G3P800
- iSpring RCC7AK
- Crystal Quest Arsenic Filter
Water Quality by ZIP Code in Largo
Water quality varies across Largo's ZIP codes. The table below shows the worst-scoring and best-scoring areas:
| ZIP Code | Score | Grade | Violations | Health-Based |
|---|---|---|---|---|
| 33770 | 66 | C | 9 | 0 |
| 33774 | 66 | C | 9 | 0 |
| 33771 | 71 | B | 9 | 0 |
| 33773 | 71 | B | 9 | 0 |
| 33778 | 76 | B | 9 | 0 |
| 33779 | 83 | B | 9 | 0 |
Common Questions About Largo Water
These are the most common questions residents search for about water quality in Largo, Florida:
Is Largo water hard or soft? Water hardness varies by source. Largo's 4 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Largo tap water? Largo's water receives a grade of C (60/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Largo? Based on detected contaminants, a uv disinfection system (poe or pou) filter is most recommended. See our Water Filter Matcher for personalized recommendations.
Largo vs. Florida Average
Understanding how Largo compares to the broader Florida 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 Largo.
ZIP Codes in Largo
Largo spans 6 ZIP codes. The ZIP with the lowest water quality score is 33770. 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.