Lead pipes by county in Maryland
Lead, galvanized and unknown service lines reported by the water systems serving each Maryland county.
| County | Lead | Galv. | Unknown | Systems |
|---|---|---|---|---|
| Allegany County | 0 | 64 | 19,801 | 11 |
| Anne Arundel County | 0 | 174 | 18,022 | 17 |
| Baltimore City | 47 | 385 | 335,694 | 2 |
| Baltimore County | 0 | 0 | 62 | 2 |
| Calvert County | 0 | 12 | 2,037 | 18 |
| Caroline County | 1 | 617 | 1,978 | 8 |
| Carroll County | 2 | 64 | 4,442 | 11 |
| Cecil County | 0 | 0 | 2,287 | 12 |
| Charles County | 2 | 28 | 6,182 | 30 |
| Dorchester County | 0 | 0 | 7,068 | 8 |
| Frederick County | 22 | 188 | 15,616 | 21 |
| Garrett County | 2 | 0 | 3,333 | 10 |
| Harford County | 0 | 0 | 14,848 | 8 |
| Howard County | 0 | 1 | 16,800 | 1 |
| Kent County | 0 | 1 | 2,162 | 9 |
| Montgomery County | 8 | 1,277 | 65,510 | 4 |
| Prince George'S County | 0 | 0 | 11 | 2 |
| Queen Anne'S County | 0 | 0 | 5,224 | 9 |
| Somerset County | 0 | 0 | 564 | 3 |
| St. Mary'S County | 0 | 32 | 193 | 10 |
| Talbot County | 0 | 0 | 4,821 | 4 |
| Washington County | 22 | 100 | 21,556 | 11 |
| Wicomico County | 3 | 84 | 10,080 | 8 |
| Worcester County | 0 | 0 | 5,106 | 6 |
Systems serving several counties are counted in each. Source: EPA SDWIS service line inventory, 2026 Q3.