Lead in Delaware Drinking Water
Ranked by 90th percentile lead level (ppb) · Data from EPA SDWIS & UCMR
Lead in Delaware: what the data shows
Delaware has 43 cities with lead monitoring data, with very few cities exceeding the EPA action level of 15 ppb. The state average 90th percentile lead level is 2.6 ppb, compared to 3.3 ppb nationally — better than the national average. 1 city exceeds the 15 ppb action level. High lead levels in tap water typically indicate aging infrastructure — lead service lines, lead solder in older plumbing, or lead-containing brass fixtures. There is no safe level of lead exposure for children. The 90th percentile measurement means that 90% of tap samples in a city are at or below the reported level. This is the standard EPA uses under the Lead and Copper Rule to determine if a water system needs to take corrective action. An NSF 53-certified pitcher or under-sink filter can effectively remove lead at the tap.
Cities exceeding 15 ppb EPA Action Level
Lead data across Delaware
Each dot is a city, colored by overall water quality grade. Cities with lead levels above the 15 ppb EPA action level are highlighted. Size reflects population served.
Top 10 cities by lead level in Delaware
Highest Lead levels (ppb)
All Delaware cities ranked by lead level
| # | City | Level | Level | Exceeds? | Violations | Grade |
|---|---|---|---|---|---|---|
| 1 | Lewes | 23.0 ppb | Yes | 20 | D+ | |
| 2 | Georgetown | 13.7 ppb | No | 56 | F | |
| 3 | Seaford | 12.7 ppb | No | 38 | F | |
| 4 | Winterthur | 12.0 ppb | No | 0 | B+ | |
| 5 | Milton | 7.2 ppb | No | 10 | B | |
| 6 | Dewey Beach | 6.9 ppb | No | 12 | C+ | |
| 7 | Dagsboro | 6.0 ppb | No | 52 | B | |
| 8 | Bethany Beach | 4.9 ppb | No | 5 | B+ | |
| 9 | Dover Afb | 3.5 ppb | No | 3 | A | |
| 10 | Millsboro | 2.6 ppb | No | 77 | D | |
| 11 | Ocean View | 2.5 ppb | No | 12 | A- | |
| 12 | Wilmington | 2.0 ppb | No | 8 | B | |
| 13 | Dover | 2.0 ppb | No | 35 | B | |
| 14 | Delmar | 2.0 ppb | No | 7 | B | |
| 15 | Fenwick Island | 1.8 ppb | No | 0 | A- | |
| 16 | Magnolia | 1.6 ppb | No | 27 | B | |
| 17 | Milford | 1.5 ppb | No | 12 | A- | |
| 18 | Bear | 1.0 ppb | No | 3 | B | |
| 19 | Bear | 1.0 ppb | No | 3 | B | |
| 20 | Delaware City | 1.0 ppb | No | 0 | A+ | |
| 21 | Davenport | 1.0 ppb | No | 1 | B | |
| 22 | Slaughter Beach | 1.0 ppb | No | 1 | A+ | |
| 23 | Kenton | 0.3 ppb | No | 23 | A- | |
| 24 | Rehoboth Beach | 0.0 ppb | No | 8 | B | |
| 25 | New Castle | 0.0 ppb | No | 9 | B- | |
| 26 | Millville | 0.0 ppb | No | 27 | B | |
| 27 | Newark | 0.0 ppb | No | 5 | C- | |
| 28 | Middletown | 0.0 ppb | No | 17 | B+ | |
| 29 | Smyrna | 0.0 ppb | No | 14 | C | |
| 30 | Camden-Wyoming | 0.0 ppb | No | 35 | B | |
| 31 | Bridgeville | 0.0 ppb | No | 6 | B+ | |
| 32 | Clayton | 0.0 ppb | No | 1 | A- | |
| 33 | Odessa | 0.0 ppb | No | 2 | A- | |
| 34 | Laurel | 0.0 ppb | No | 59 | B | |
| 35 | Harrington | 0.0 ppb | No | 7 | B+ | |
| 36 | Selbyville | 0.0 ppb | No | 6 | A | |
| 37 | Cheswold | 0.0 ppb | No | 20 | B+ | |
| 38 | Felton | 0.0 ppb | No | 41 | B- | |
| 39 | Frederica | 0.0 ppb | No | 12 | A | |
| 40 | Ellendale | 0.0 ppb | No | 19 | A- | |
| 41 | Greenwood | 0.0 ppb | No | 20 | B+ | |
| 42 | Lincoln | 0.0 ppb | No | 20 | B+ | |
| 43 | Frankford | 0.0 ppb | No | 20 | B |
Frequently asked questions about lead in Delaware
Is lead in Delaware tap water a concern?
Yes — 1 of 43 cities with lead data exceed the EPA action level of 15 ppb. The state average is 2.6 ppb. Even below the action level, lead poses health risks especially for children and pregnant women. If your home was built before 1986, consider testing your tap water directly.
How can I reduce lead exposure from Delaware tap water?
Use an NSF 53-certified water filter, which is specifically certified to reduce lead. Run your cold tap for 30 seconds before drinking or cooking, especially if water has been sitting in pipes for hours. Never use hot tap water for cooking or making baby formula, as heat increases lead leaching from pipes.
Which Delaware cities have the highest lead levels?
The cities with the highest 90th percentile lead levels in Delaware are: Lewes (23.0 ppb), Georgetown (13.7 ppb), Seaford (12.7 ppb), Winterthur (12.0 ppb), Milton (7.2 ppb). See the full ranked table above.