Delaware Water Quality & Safety Report
41 ZIP codes · 127 water systems · IPC plumbing code · Updated 2026-03-16
Data: EPA SDWIS, NWS, State plumbing boards, Rewiring America Last verified: 2026-03-16
Overview
We track water quality, weather alerts, plumbing regulations, and energy rebates for 41 ZIP codes across Delaware, covering 127 community water systems that serve approximately 655,166 people.
19 of 41 ZIP codes (46%) have recorded EPA violations. 11 health-based violations have been documented.
Plumbing Regulations
Delaware follows the International Plumbing Code (2021 edition).
- Plumbing code: IPC (2021)
- Homeowner DIY: Licensed plumber required
- Water heater permit: Required
- Annual backflow test: Required
Energy & Water Rebates
Across 41 tracked ZIP codes in Delaware, residents have access to an average of 2 water-related rebate programs — including incentives for heat pump water heaters, efficient fixtures, and plumbing upgrades.
Check rebates for your ZIP code →
Areas with Most Violations
| ZIP Code | City | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|---|
| 19967 | Millville | — | 8 | 4 | BETHANY BAY PUMP DISTRICT |
| 19952 | Harrington | — | 6 | 0 | HARRINGTON WATER DEPARTMENT |
| 19901 | Dover | — | 5 | 3 | REHOBOTH PUMP DISTRICT (TUI) |
| 19950 | Greenwood | — | 5 | 1 | GREENWOOD WATER DEPARTMENT |
| 19960 | Lincoln | — | 5 | 2 | CEDAR VILLAGE LLC |
| 19702 | Newark | — | 4 | 0 | ARTESIAN WATER COMPANY |
| 19941 | Ellendale | — | 4 | 0 | INGRAM VILLAGE (AWC) |
| 19947 | Georgetown | — | 4 | 0 | GEORGETOWN WATER DEPARTMENT |
| 19956 | Laurel | — | 4 | 0 | LAUREL WATER DEPARTMENT |
| 19707 | Hockessin | — | 3 | 0 | CARPENTERS ROW |
Areas with No Violations
| ZIP Code | City | Safety Score | System | Population |
|---|---|---|---|---|
| 19701 | Bear | — | VILLAGEBROOK | 847 |
| 19706 | Delaware City | — | DELAWARE CITY WATER DEPARTMENT (AWC) | 2,610 |
| 19709 | Middletown | — | MIDDLETOWN WATER DEPARTMENT | 17,700 |
| 19720 | New Castle | — | MUNICIPAL SERVICES COMMISSION | 5,549 |
| 19730 | Odessa | — | EAST NCC DISTRICT | 5,538 |
| 19731 | Port Penn | — | BAYVIEW IMPROVEMENT COMPANY (AWC) | 214 |
| 19734 | Townsend | — | FREDERICK LODGE PUMP DISTRICT | 204 |
| 19735 | Winterthur | — | WINTERTHUR | 687 |
| 19902 | Dover Afb | — | DOVER AIR FORCE BASE | 11,000 |
| 19930 | Bethany Beach | — | ARTESIAN SOUTHERN SUSSEX REGIONAL | 18,015 |
Lead & Copper
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
- High risk (Zone 1): 0 ZIP codes (0%)
- Moderate risk (Zone 2): 0 ZIP codes
- Low risk (Zone 3): 0 ZIP codes
All 41 ZIP Codes in Delaware
- 19701 (Bear)
- 19930 (Bethany Beach)
- 19933 (Bridgeville)
- 19936 (Cheswold) — 3 violations
- 19938 (Clayton)
- 19939 (Dagsboro) — 3 violations
- 19706 (Delaware City)
- 19940 (Delmar)
- 19901 (Dover) — 5 violations ⚠
- 19902 (Dover Afb)
- 19941 (Ellendale) — 4 violations
- 19943 (Felton) — 1 violation
- 19944 (Fenwick Island)
- 19945 (Frankford)
- 19946 (Frederica)
- 19947 (Georgetown) — 4 violations
- 19950 (Greenwood) — 5 violations ⚠
- 19951 (Harbeson)
- 19952 (Harrington) — 6 violations
- 19953 (Hartly) — 1 violation
- 19707 (Hockessin) — 3 violations
- 19955 (Kenton) — 3 violations
- 19956 (Laurel) — 4 violations
- 19958 (Lewes)
- 19960 (Lincoln) — 5 violations ⚠
- 19961 (Little Creek) — 3 violations ⚠
- 19962 (Magnolia) — 2 violations
- 19964 (Marydel)
- 19709 (Middletown)
- 19963 (Milford)
- 19966 (Millsboro)
- 19967 (Millville) — 8 violations ⚠
- 19968 (Milton)
- 19710 (Montchanin) — 3 violations
- 19720 (New Castle)
- 19702 (Newark) — 4 violations
- 19730 (Odessa)
- 19731 (Port Penn)
- 19734 (Townsend)
- 19801 (Wilmington) — 3 violations
- 19735 (Winterthur)
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Regulations: State plumbing boards, ICC, IAPMO
- Rebates: Rewiring America
Updated daily.