Suffolk County, New York
95 ZIP codes · Avg score 68/100 · Grade C · Updated 2026-06-03
Water safety in Suffolk County is uneven — some of its 95 ZIP codes meet standards cleanly while others carry documented violations.
How Suffolk County Compares
How Suffolk County Compares
Suffolk County scores 7 points above the New York state average (61/100) and 0 points above the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Suffolk County, New York
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 11.2 (asthma 10.2%, diabetes 10%)
Estimated additional annual cost per homeowner: $4,192, driven primarily by flood
Infrastructure: 0.434% avg pipe failure probability, 67% of ZIPs at high risk
71.7% of homes built before 1978 (lead paint era)
Violation History (2022–2025)
→ Stable trendEPA violation counts by year across Suffolk County water systems. Health-based shown in red, total in blue.
Peak year: 2024 with 16 violations. Past 5 years: 37 total (37 health-based).
Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.
County Health Indicators vs National Average
Black markers indicate national averages. Source: CDC PLACES, Census ACS.
Infrastructure Overview
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $4,192
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
547,125 housing units in Suffolk County
Source: U.S. Census Bureau ACS B25034 (Year Structure Built).
Water Safety Affordability
How much it costs to fix water issues relative to home values in Suffolk County
Remediation costs are relatively manageable for most homeowners in Suffolk County, representing a small fraction of property value.
Remediation includes water filtration, lead abatement, radon mitigation, and flood protection where applicable. Source: Census ACS, EPA SDWIS.
Health Outcomes vs National Average
CDC PLACES data for Suffolk County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water Systems with Most Violations
Top 5 systems in Suffolk County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | SUFFOLK COUNTY WATER AUTHORITY | 1,100,000 | 89 |
| 2 | New York City System | 8,271,000 | 47 |
| 3 | Leisure Lake Estates | 285 | 35 |
| 4 | Ravenwood Estates | 200 | 35 |
| 5 | Yeshiva Kehileth Yakov | 150 | 35 |
43 total water systems serve Suffolk County.
All ZIP Codes in Suffolk County
95 ZIP codes tracked in Suffolk County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 11969 | Southampton | 95 | A | 1 | — |
| 2 | 11973 | Upton | 95 | A | 0 | — |
| 3 | 13438 | Remsen | 93 | A | 2 | $177K |
| 4 | 11754 | Kings Park | 90 | A | 0 | $595K |
| 5 | 11763 | Medford | 90 | A | 1 | $435K |
| 6 | 11933 | Calverton | 89 | A | 2 | $430K |
| 7 | 11965 | Shelter Island Heights | 89 | A | 2 | $1092K |
| 8 | 6390 | Fishers Island | 88 | A | 5 | — |
| 9 | 11721 | Centerport | 85 | A | 1 | $705K |
| 10 | 11787 | Smithtown | 85 | A | 0 | $642K |
| 11 | 11777 | Port Jefferson | 84 | B | 2 | $656K |
| 12 | 11964 | Shelter Island | 84 | B | 2 | $999K |
| 13 | 11052 | Port Washington | 83 | B | 3 (3 health) | — |
| 14 | 11740 | Greenlawn | 83 | B | 6 | $687K |
| 15 | 11719 | Brookhaven | 82 | B | 3 | $565K |
| 16 | 10278 | New York | 81 | B | 4 | — |
| 17 | 11788 | Hauppauge | 81 | B | 3 | $636K |
| 18 | 11946 | Hampton Bays | 80 | B | 1 | $691K |
| 19 | 11968 | Southampton | 80 | B | 1 | $1171K |
| 20 | 11751 | Islip | 77 | B | 3 | $502K |
| 21 | 11937 | East Hampton | 77 | B | 3 | $1009K |
| 22 | 10005 | New York | 76 | B | 4 | $1387K |
| 23 | 10025 | New York | 76 | B | 4 | $1125K |
| 24 | 11768 | Northport | 76 | B | 5 | $780K |
| 25 | 11901 | Riverhead | 75 | B | 7 (2 health) | $438K |
| 26 | 11795 | West Islip | 74 | B | 2 | $599K |
| 27 | 11707 | West Babylon | 73 | B | 0 | — |
| 28 | 11749 | Islandia | 73 | B | 0 | $452K |
| 29 | 11770 | Ocean Beach | 73 | B | 1 | $731K |
| 30 | 11949 | Manorville | 73 | B | 0 | $546K |
| 31 | 11953 | Middle Island | 73 | B | 0 | $358K |
| 32 | 11961 | Ridge | 73 | B | 0 | $403K |
| 33 | 11972 | Speonk | 73 | B | 0 | $852K |
| 34 | 11980 | Yaphank | 73 | B | 0 | $410K |
| 35 | 11702 | Babylon | 72 | B | 3 | $599K |
| 36 | 11944 | Greenport | 71 | B | 16 | $822K |
| 37 | 11971 | Southold | 71 | B | 6 | $763K |
| 38 | 11743 | Huntington | 66 | C | 16 | $748K |
| 39 | 11716 | Bohemia | 65 | C | 0 | $509K |
| 40 | 11717 | Brentwood | 65 | C | 0 | — |
| 41 | 11722 | Central Islip | 65 | C | 0 | $407K |
| 42 | 11724 | Cold Spring Harbor | 65 | C | 0 | $1572K |
| 43 | 11725 | Commack | 65 | C | 0 | $643K |
| 44 | 11731 | East Northport | 65 | C | 0 | $622K |
| 45 | 11739 | Great River | 65 | C | 0 | $840K |
| 46 | 11752 | Islip Terrace | 65 | C | 0 | $482K |
| 47 | 11755 | Lake Grove | 65 | C | 0 | $559K |
| 48 | 11767 | Nesconset | 65 | C | 0 | $616K |
| 49 | 11778 | Rocky Point | 65 | C | 0 | $411K |
| 50 | 11786 | Shoreham | 65 | C | 0 | $540K |
| 51 | 11796 | West Sayville | 65 | C | 0 | $572K |
| 52 | 11941 | Eastport | 65 | C | 0 | $636K |
| 53 | 11950 | Mastic | 65 | C | 0 | $373K |
| 54 | 11955 | Moriches | 65 | C | 0 | $467K |
| 55 | 11956 | New Suffolk | 65 | C | 0 | $1034K |
| 56 | 11958 | Peconic | 65 | C | 0 | $831K |
| 57 | 11975 | Wainscott | 65 | C | 0 | $2000K |
| 58 | 11233 | Brooklyn | 62 | C | 35 (19 health) | $1013K |
| 59 | 11703 | North Babylon | 60 | C | 0 | $470K |
| 60 | 11713 | Bellport | 60 | C | 0 | $475K |
| 61 | 11718 | Brightwaters | 60 | C | 0 | $711K |
| 62 | 11729 | Deer Park | 60 | C | 0 | $496K |
| 63 | 11730 | East Islip | 60 | C | 0 | $578K |
| 64 | 11746 | Huntington Station | 60 | C | 0 | $665K |
| 65 | 11779 | Ronkonkoma | 60 | C | 0 | $465K |
| 66 | 11780 | Saint James | 60 | C | 0 | $703K |
| 67 | 11792 | Wading River | 60 | C | 0 | $558K |
| 68 | 11931 | Aquebogue | 60 | C | 0 | — |
| 69 | 11932 | Bridgehampton | 60 | C | 0 | $1951K |
| 70 | 11935 | Cutchogue | 60 | C | 0 | $886K |
| 71 | 11940 | East Moriches | 60 | C | 0 | $626K |
| 72 | 11947 | Jamesport | 60 | C | 0 | — |
| 73 | 11948 | Laurel | 60 | C | 0 | $909K |
| 74 | 11962 | Sagaponack | 60 | C | 0 | $1933K |
| 75 | 11970 | South Jamesport | 60 | C | 0 | $729K |
| 76 | 11976 | Water Mill | 60 | C | 0 | $2000K |
| 77 | 11704 | West Babylon | 55 | C | 0 | $485K |
| 78 | 11726 | Copiague | 55 | C | 0 | $451K |
| 79 | 11769 | Oakdale | 55 | C | 0 | $586K |
| 80 | 11930 | Amagansett | 55 | C | 0 | $1997K |
| 81 | 11934 | Center Moriches | 55 | C | 0 | $557K |
| 82 | 11942 | East Quogue | 55 | C | 0 | $801K |
| 83 | 11952 | Mattituck | 55 | C | 0 | $715K |
| 84 | 11954 | Montauk | 55 | C | 0 | $1186K |
| 85 | 11959 | Quogue | 55 | C | 0 | $1781K |
| 86 | 11960 | Remsenburg | 55 | C | 0 | $1231K |
| 87 | 11963 | Sag Harbor | 55 | C | 0 | $1117K |
| 88 | 11967 | Shirley | 55 | C | 0 | $386K |
| 89 | 11977 | Westhampton | 55 | C | 0 | $1039K |
| 90 | 11701 | Amityville | 50 | D | 0 | $489K |
| 91 | 11706 | Bay Shore | 50 | D | 0 | $464K |
| 92 | 11782 | Sayville | 50 | D | 0 | $614K |
| 93 | 11951 | Mastic Beach | 50 | D | 0 | $321K |
| 94 | 11978 | Westhampton Beach | 50 | D | 0 | $1045K |
| 95 | 11757 | Lindenhurst | 49 | D | 2 | $480K |
Recommended Buyer Guides for Suffolk County
Retailer arrangements don't shape what appears here — the selection logic is independent, filtered against EPA detections and the federal hazard data on file for this county.
- Best Water Filters for Lead — Lead above EPA action level in 1 ZIP code
- Best Lead Paint Test Kits — 71.7% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best Sump Pumps — Flood is the top compound risk factor
- Best Mold Test Kits — Flood-driven moisture and mold risk
Deep Dive Reports
Detailed analysis for Suffolk County, New York
Overview
Suffolk County in New York covers 95 ZIP codes with an average Home Safety Score of C (68/100).
30 of 95 ZIP codes have recorded EPA violations. 24 health-based violations have been documented.
← Back to New York water quality report
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Updated daily.