Water Quality in Old Greenwich, CT: No Violations — Grade F
Grade F · Score 35/100 · 1 water system · Updated 2026-05-03
Old Greenwich's water has serious compliance issues. Independent testing and filtration are strongly recommended.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Across all 1 water system serving Old Greenwich, CT, federal monitoring data documents zero EPA violations — no MCL exceedances, no monitoring lapses, no enforcement actions anywhere in the compliance history.
Water Quality by ZIP Code in Old Greenwich
Water quality varies across Old Greenwich's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 06870 | F | 35 | 0 | 0 | View report → |
Water Quality Overview
Old Greenwich, Connecticut receives a water quality grade of F with an overall score of 35 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
No EPA violations have been recorded for the 1 water system serving Old Greenwich. 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 F Means
A grade of F indicates serious compliance issues. Old Greenwich's water systems have substantial violations. Residents should strongly consider independent water testing and appropriate filtration.
Lead Levels
Lead testing data for Old Greenwich is currently being collected. The EPA requires all community water systems to test for lead under the Lead and Copper Rule.
With 72% of homes built before 1986, Old Greenwich 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
Old Greenwich 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 Old Greenwich
Old Greenwich is served by 1 community water system regulated under the Safe Drinking Water Act. These systems collectively serve approximately 233 people across 1 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
How to Check Your Water in Old Greenwich
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
Old Greenwich vs. Nearby Connecticut Cities
How Old Greenwich's water quality compares to similar cities in Connecticut:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Old Greenwich | F | 0 | 1 | 233 |
| Darien | F | 0 | 1 | 233 |
| Riverside | D | 0 | 1 | 233 |
| Avon | B | 6 | 1 | 238 |
Common Questions About Old Greenwich Water
These are the most common questions residents search for about water quality in Old Greenwich, Connecticut:
Is Old Greenwich water hard or soft? Water hardness varies by source. Old Greenwich's 1 water system uses a single source. Check your ZIP code report for specific hardness data.
Can I drink Old Greenwich tap water? Old Greenwich's water receives a grade of F (35/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Old Greenwich? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Old Greenwich vs. Connecticut Average
Understanding how Old Greenwich compares to the broader Connecticut 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 Old Greenwich.
ZIP Codes in Old Greenwich
Old Greenwich spans 1 ZIP code. 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.