Delaware Water Quality Report 2026
Delaware tap water is safe — filtration recommended based on our analysis of 3 water systems serving 141,615 residents. The average PurityMap score is 82.0/100 (Grade: B), which is 4.1 points above the national average.
- 1 cities have lead at or above 5 ppb. Homes built before 1986 are at highest risk.
- 3 cities use chloramine or have elevated chlorine residuals. Standard Brita pitchers do not remove chloramine.
Delaware water is generally good quality. A carbon pitcher or faucet filter removes chlorine taste and provides extra protection. No major filtration investment is needed for most residents.
Soft
Delaware is 4.1 points above the US average of 77.9/100. Hardness is 3.1 GPG below the US average of 6.3 GPG.
All 3 cities score similarly
How Delaware's 3 cities score on the PurityMap 0–100 scale:
Water quality for the most populated cities. Click any city for details.
| City | Population | Score | Hardness | Key Issues |
|---|---|---|---|---|
| Wilmington | 71K | 82/100 | 3.5 GPG | Lead |
| Dover | 37K | 82/100 | 2.8 GPG | — |
| Newark | 33K | 82/100 | 3.2 GPG | — |
Delaware generally has soft to moderate water. Average: 3.2 GPG (Soft). Most residents do not need a softener.
Based on EPA UCMR5 data, PFAS have not been detected above advisory levels in any Delaware cities in our database as of 2026. 1 cities have pending PFAS testing data.
1 cities in Delaware have lead at or above 5 ppb. Highest: Wilmington at 5.5 ppb. No safe level of lead exists. Cities: Wilmington.
Where Delaware gets its drinking water, based on 3 water systems.
| Source Type | Cities | % of Total |
|---|---|---|
| Surface Water | 1 | 33% |
| Groundwater | 1 | 33% |
| Mixed (Ground + Surface) | 1 | 33% |
1 cities have elevated lead. NSF 53 under-sink filter or RO recommended.
| # | City | Pop. | Score | Hardness | Lead | PFAS | TDS |
|---|---|---|---|---|---|---|---|
| 1 | Wilmington | 71K | 82/100 | 3.5 GPG (Soft) | 5.5 ppb | ❓ Pending | 120 ppm |
| 2 | Dover | 37K | 82/100 | 2.8 GPG (Soft) | 2.5 ppb | ✅ No | 120 ppm |
| 3 | Newark | 33K | 82/100 | 3.2 GPG (Soft) | 3.8 ppb | ✅ No | 130 ppm |
Delaware has 3 utilities. Major: Artesian Water Company, City of Dover Public Utilities, City of Newark Water Department.
Sources: Brandywine Creek, Groundwater, Groundwater and White Clay Creek.
- EPA Safe Drinking Water Information System
- EWG Tap Water Database
- State utility Consumer Confidence Reports
- USGS regional water monitoring data
PurityMap compiles publicly available data and does not perform independent testing.
3 city water quality reports available for Delaware.
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