EPA data as of Oct 2026 · page updated 2026-10-29
Delaware: drinking water & radon
Delaware has 203 active community water systems. Since 2016, 26 reported health-based violations; 1 had a latest lead result above 15 ppb; 13 measured PFOA or PFOS at or above 4 ppt.
Water systems203
With violations26
Radon zone 1 ZIPs0
ZIPs likely on wells9
Radon zones in Delaware
tap a countyZone 1 · highestZone 2 · moderateZone 3 · low
Most health-based violations
| Forest Park 25 people | 7 |
| Cherry Creek Valley 78 people | 6 |
| Evergreen Post Acute 256 people | 5 |
| Fish Hook Mobile Home Park 72 people | 3 |
| Tall Pines Resort Community Sys1 538 people | 3 |
| Selbyville Water Department 3,502 people | 3 |
| Home Town Village of Cool Branch 654 people | 3 |
| Carey Estates, LLC 312 people | 2 |
| Avalon Woods Owners Assoc INC 306 people | 2 |
| Country Club Village (Tui) 192 people | 2 |
Highest latest lead (90th percentile)
| Lewes Board of Public Works 9,627 people | 21.6 ppb |
| Sand Hill Acres 384 people | 13.7 ppb |
| St Andrews Apartment New Addition 272 people | 12.7 ppb |
| Winterthur 687 people | 12 ppb |
| Whispering Pines Mobile Home Park 325 people | 11.5 ppb |
| Carey Estates, LLC 312 people | 11.4 ppb |
| Silver View Farm 398 people | 11 ppb |
| Ascot Landing Subdivision 338 people | 10.4 ppb |
| Country Living Mobile Court 255 people | 10.3 ppb |
| Meadows at Cubbage Pond 201 people | 9.7 ppb |
Highest PFOA / PFOS
| Georgetown Water Department 7,259 people | 36 ppt |
| Newark Water Department 40,000 people | 25.3 ppt |
| Veolia Water Delaware, INC 100,495 people | 24.4 ppt |
| Artesian Water Company 231,114 people | 23.1 ppt |
| Rehoboth Beach Water Department 25,000 people | 14.9 ppt |
| Dewey Beach Water Department 31,000 people | 11 ppt |
| Wilmington Water Department 107,976 people | 9.9 ppt |
| Smyrna Water Department 11,813 people | 9.8 ppt |
| Lewes Board of Public Works 9,627 people | 9.5 ppt |
| Bethany Bay Pump District 52,684 people | 6.1 ppt |
Largest systems
| Artesian Water Company 231,114 people | 231,114 |
| Wilmington Water Department 107,976 people | 107,976 |
| Veolia Water Delaware, INC 100,495 people | 100,495 |
| Rehoboth Pump District (Tui) 81,417 people | 81,417 |
| Bethany Bay Pump District 52,684 people | 52,684 |
| Newark Water Department 40,000 people | 40,000 |
| Dover Water Department 39,491 people | 39,491 |
| Dewey Beach Water Department 31,000 people | 31,000 |
| Rehoboth Beach Water Department 25,000 people | 25,000 |
| Artesian Southern Sussex Regional 20,145 people | 20,145 |
All ZIP codes in Delaware
93 ZIP codes.
19701Bear19702Newark19703Claymont19706Delaware City19707Hockessin19708Kirkwood19709Middletown19710Montchanin19711Newark19712Newark19713Newark19714Newark19715Newark19716Newark19717Newark19718Newark19720New Castle19721New Castle19725Newark19726New Castle19730Odessa19731Port Penn19732Rockland19734Townsend19735Winterthur19801Wilmington19802Wilmington19803Wilmington19804Wilmington19805Wilmington19806Wilmington19807Wilmington19808Wilmington19809Wilmington19810Wilmington19850Wilmington19880Wilmington19884Wilmington19885Wilmington19886Wilmington19890Wilmington19891Wilmington19892Wilmington19893Wilmington19894Wilmington19895Wilmington19896Wilmington19897Wilmington19898Wilmington19899Wilmington19901Dover19902Dover Afb19903Dover19904Dover19905Dover19906Dover19930Bethany Beach19931Bethel19933Bridgeville19934Camden Wyoming19936Cheswold19938Clayton19939Dagsboro19940Delmar19941Ellendale19943Felton19944Fenwick Island19945Frankford19946Frederica19947Georgetown19950Greenwood19951Harbeson19952Harrington19953Hartly19954Houston19955Kenton19956Laurel19958Lewes19960Lincoln19961Little Creek19962Magnolia19963Milford19964Marydel19966Millsboro19967Millville19968Milton19969Nassau19970Ocean View19971Rehoboth Beach19973Seaford19975Selbyville19977Smyrna19979Viola
What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.
Questions
How many water systems in Delaware have violations?
26 of 203 active community water systems in Delaware reported at least one health-based violation since 2016 (EPA SDWIS).
What is the radon risk in Delaware?
No ZIP codes are in EPA radon zone 1, 50 in zone 2 and 43 in zone 3. EPA recommends testing every home.