ZipCheckup grade for 11791: A.
Checked records flag no major concern; missing data is unknown.
Syosset, NY (11791): PFAS Detected in Mapped Water Systems - 99/100
EPA data combined for 6 water systems mapped to this ZIP (largest mapped system: Jericho Water District)
Health-based violation records by water system:
EPA records for the water systems mapped to 11791 in Syosset, NY contain 1 recorded violations for inclusive record years 2021 through 2026, all mapped systems combined; 1 are marked health-based.
Data source: U.S. Environmental Protection Agency (EPA) SDWIS
At a Glance
- Water EPA records for water systems mapped to this ZIP show 1 health-based violation (since 2021).
- Lead The reported 90th-percentile lead result is below the laboratory reporting limit, not a measured zero; EPA's health goal for lead is zero.
- PFAS PFAS detected in UCMR5 sampling; see the PFAS section for each compound, compared with the federal PFAS MCL where one exists.
- Radon EPA Zone 3 - county-level radon potential, not evidence of a low home result.
- Flood 34 cumulative NFIP claim records. Check the current FEMA map for a specific address.
Get updates when new water-quality data is available for your area
Free alerts when new EPA data affects ZIP code 11791. No spam - just safety updates.
Unsubscribe anytime. We only send updates when your safety score changes. See our Privacy Policy.
See incorrect data? Let us know
Records for Syosset (11791) show 1 high-priority flag and no critical-level flag on record.
Score Breakdown
Overall Home Safety Score: 99/100
This is the published model score. Component and domain values are shown independently; they are not added together on this page.
Canonical components
Required domains
Coverage: 4 of 4 components and 3 of 3 domains observed.
Model 4.0.0; series home-safety-v4-cross-vertical.
Safety & Health (8) CRITICAL
Your Water System
ZIP code 11791 in Syosset, New York is mapped to the water system Jericho Water District (EPA ID: NY2902831). This system provides water to approximately 58,000 people from groundwater sources.
There are 6 community water systems serving this area.
Lead & Copper in Your Water
The EPA requires water systems to monitor lead and copper levels under the Lead and Copper Rule.
| Metal | Measured Level | EPA Action Level | Status | Sample Date or Period |
|---|---|---|---|---|
| Copper | Action-level exceedance on record | 1.3 mg/L | Exceeds action level | Not present in ZipCheckup accepted source data |
Water Systems Serving This Area
| System Name | EPA ID | Population | Source |
|---|---|---|---|
| Jericho Water District | NY2902831 | 58,000 | Groundwater |
| Hicksville Water District | NY2902829 | 48,000 | Groundwater |
| Oyster Bay Water District | NY2902844 | 8,700 | Groundwater |
| Plainview Water District | NY2902845 | 34,000 | Groundwater |
| Liberty Utilities New York - Mill Neck | NY2902838 | 280 | Groundwater |
Other Water Quality Reports in New York
- 06390 (Fishers Island)
- 10001 (New York)
- 10002 (New York)
- 10003 (New York)
- 10004 (New York)
- 10005 (New York)
- 10006 (New York)
- 10007 (New York)
- 10008 (New York)
- 10009 (New York)
- 10010 (New York)
- 10011 (New York)
- 10012 (New York)
- 10013 (New York)
- 10014 (New York)
- 10015 (New York)
- 10016 (New York)
- 10017 (New York)
- 10018 (New York)
- 10019 (New York)
Nearby Water Quality Reports
- 11773 (Syosset) - <1 mi
- 11797 (Woodbury) - 2 mi - 1 violation recorded for mapped water systems
- 11753 (Jericho) - 2 mi - 2 violations recorded for mapped water systems
- 11853 (Jericho) - 3 mi
- 11803 (Plainview) - 3 mi
- 11732 (East Norwich) - 3 mi - 1 violation recorded for mapped water systems
- 11802 (Hicksville) - 3 mi
- 11819 (Hicksville) - 3 mi
- 11801 (Hicksville) - 4 mi - 1 violation recorded for mapped water systems
- 11771 (Oyster Bay) - 4 mi - 2 violations recorded for mapped water systems
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for Jericho Water District (NY2902831) on EPA.gov.
4 of the top compounds applied across the surrounding county in USGS pesticide-use estimates appear on EPA drinking-water monitoring lists. See the agricultural pesticide-use section.
PFAS Contamination Detected
PFAS ("forever chemicals") have been reported in samples from water systems associated with ZIP code 11791.
Detected compounds: PFBA, PFPeA, PFHxA, 6:2 FTS, PFHpA.
Highest measured level: 0.067 µg/L
Reverse osmosis (RO) and activated carbon block filters can reduce PFAS at the tap. Certifications list the compounds covered: an NSF/ANSI 53 or 58 claim for PFOA/PFOS does not cover every PFAS, so check that the product lists the compounds detected here.
Environmental Hazards (11) CRITICAL
Home & Infrastructure (7) OK
Cost & Community (9) HIGH
CPSC product recall notices
These national notices are not matched to this ZIP code or water system.
Protect Your Home in Syosset
Based on local data for ZIP 11791, these services may benefit homeowners in your area.
Based on local data for your area. Use the tools below to explore your options.
Home & Flood Insurance
The ZIP code for this report in Syosset has 34 FEMA flood claims on record. Standard homeowner policies don't cover flood damage - make sure you're protected.
Typical cost: Flood insurance: premiums vary by property and flood zone; request a quote
Check Your Flood Zone (Free)FEMA flood map lookup - see if your property is in a flood zone
Free tip: Check your FEMA flood zone at msc.fema.gov (free lookup)
Gutter Installation & Repair
The median home in 11791 was built around 1951. Aging gutters can cause foundation damage, basement flooding, and mold - a professional assessment can prevent costly repairs.
Typical cost: Gutter installation: typically $1,000–$2,500 for a standard home
Estimate Your Home Maintenance CostsWindow Replacement
The median build year of homes in Syosset is 1951; check the age and condition of your own windows. ENERGY STAR windows can save $101–$583/year on energy bills.
Typical cost: Window replacement: typically $300–$800 per window installed
Estimate Your Home Maintenance CostsRoofing Inspection & Repair
Homes built around 1951 may be on their second or third roof. A professional inspection can catch damage before leaks start.
Typical cost: Roof inspection: typically $75–$300; repairs $300–$1,500
Estimate Your Home Insurance NeedsService recommendations are based on public data for this ZIP code (FEMA, Census ACS, NWS). Actual needs vary by property. By calling, your information will be shared with an independent service provider. ZipCheckup may receive compensation. Cost estimates are approximate and vary by property, condition, and contractor.
Frequently Asked Questions
Is the tap water in 11791 safe to drink?
EPA SDWIS records 1 violation since 2021 across the water systems mapped to ZIP 11791 (primary system: Jericho Water District), including 1 health-based. The violation table above shows which system each record belongs to. ZipCheckup last updated this page in July 2026. The federal source release date is unavailable, so that month is not presented as source currency.
Where does 11791's water come from?
The recorded water source for Jericho Water District, a system mapped to ZIP code 11791, is Groundwater. This system serves approximately 58,000 people.
How does Syosset water compare to the national average?
Syosset's Home Safety Score ranks better than 91% of U.S. ZIP codes, and at or above 65% within New York.
How can I get my water tested in Syosset?
If Jericho Water District supplies your home, contact it for its Consumer Confidence Report; otherwise contact the water utility that serves your address, or hire a certified lab for independent home water testing. The EPA recommends annual testing if you use a private well.
What is the radon risk for 11791?
11791 is mapped to a county in EPA Radon Zone 3 (low county-level radon potential; EPA recommends testing every home), located in Nassau County. EPA radon zones range from Zone 1 (highest county-level potential) to Zone 3 (lowest). Testing your home is recommended regardless of zone.
Are there PFAS (forever chemicals) in 11791's water?
Yes, PFAS have been detected in samples from water systems mapped to 11791. Reverse osmosis and activated carbon filters certified to NSF/ANSI 53 or 58 specifically for PFOA/PFOS reduction can reduce PFAS.
What does the NFIP claim history show for ZIP 11791?
FEMA records contain 34 flood insurance claims filed in ZIP code 11791; the recorded rated-zone value (the most frequent one if there are several claims) is X, which is claims evidence and may differ from the current FEMA map zone for a property. Claim records do not establish current property risk. Review FEMA's map for the specific property.
How to cite this page
ZipCheckup. (2026). Syosset, NY (11791): PFAS Detected in Mapped Water Systems - 99/100. https://zipcheckup.com/report/11791/
@misc{zipcheckup-report-11791,
author = {{ZipCheckup}},
title = {{Syosset, NY (11791): PFAS Detected in Mapped Water Systems - 99/100}},
year = {2026},
url = {https://zipcheckup.com/report/11791/}
}
Page version: October 2026.
Nearby ZIP Code Reports
Water quality comparison for ZIP codes near 11791
| ZIP Code | City, State | Distance | Grade | Violations |
|---|---|---|---|---|
| 11773 | Syosset, NY | <1 mi | N/A | 0 |
| 11797 | Woodbury, NY | 1.6 mi | N/A | 1 |
| 11753 | Jericho, NY | 2.4 mi | N/A | 2 |
| 11853 | Jericho, NY | 2.5 mi | N/A | 0 |
| 11803 | Plainview, NY | 2.7 mi | A | 0 |
| 11732 | East Norwich, NY | 2.8 mi | N/A | 1 |
| 11802 | Hicksville, NY | 3.4 mi | N/A | 0 |
| 11819 | Hicksville, NY | 3.4 mi | N/A | 0 |
| 11801 | Hicksville, NY | 3.8 mi | A | 1 |
| 11771 | Oyster Bay, NY | 3.8 mi | A | 2 |
Nearby ZIP Code Reports
2026 Rankings for Your Area
Overall safety breakdown
Home Safety Score →Find the right water filter
Water Filter Matcher →Compare filters, tests & services
Compare My Options →Compare with another ZIP
Compare Tool →2026 Rankings
ZIP 11791 scores in the top tier nationally.