California — 10th District
119th Congress · 34 ZIP codes · Avg score 69/100 · Grade C · Updated 2026-07-19
Data: EPA SDWIS / Census 119th Congress Last verified: 2026-07-19
ZipCheckup tracks water safety for 34 ZIP codes in California's 10th District: the district earns a grade C (69/100). 161 EPA violations on record, 101 health-based.
Top Contaminants
ZIP Codes in This District
34 ZIP codes tracked in California's 10th District.
| # | ZIP Code | City | Safety Score | Grade | Violations |
|---|---|---|---|---|---|
| 1 | 94522 | Concord | 91 | A | 4 (1 health) |
| 2 | 94516 | Canyon | 81 | B | 1 |
| 3 | 94517 | Clayton | 81 | B | 1 |
| 4 | 94519 | Concord | 79 | B | 4 (1 health) |
| 5 | 94524 | Concord | 79 | B | 4 (1 health) |
| 6 | 94527 | Concord | 78 | B | 4 (1 health) |
| 7 | 94529 | Concord | 78 | B | 4 (1 health) |
| 8 | 94568 | Dublin | 77 | B | 0 |
| 9 | 94506 | Danville | 76 | B | 0 |
| 10 | 94597 | Walnut Creek | 76 | B | 1 |
| 11 | 94598 | Walnut Creek | 76 | B | 1 |
| 12 | 94531 | Antioch | 75 | B | 0 |
| 13 | 94511 | Bethel Island | 74 | B | 2 |
| 14 | 94518 | Concord | 74 | B | 4 (1 health) |
| 15 | 94520 | Concord | 74 | B | 4 (1 health) |
| 16 | 94521 | Concord | 74 | B | 4 (1 health) |
| 17 | 94523 | Pleasant Hill | 73 | B | 0 |
| 18 | 94528 | Diablo | 73 | B | 0 |
| 19 | 94553 | Martinez | 73 | B | 0 |
| 20 | 94526 | Danville | 71 | B | 0 |
| 21 | 94595 | Walnut Creek | 71 | B | 1 |
| 22 | 94596 | Walnut Creek | 71 | B | 1 |
| 23 | 94513 | Brentwood | 70 | B | 6 (2 health) |
| 24 | 94563 | Orinda | 70 | B | 0 |
| 25 | 94556 | Moraga | 66 | C | 18 (14 health) |
| 26 | 94548 | Knightsen | 63 | C | 0 |
| 27 | 94507 | Alamo | 55 | C | 0 |
| 28 | 94514 | Byron | 55 | C | 0 |
| 29 | 94561 | Oakley | 53 | D | 29 (29 health) |
| 30 | 94583 | San Ramon | 53 | D | 16 (10 health) |
| 31 | 94549 | Lafayette | 50 | D | 0 |
| 32 | 94582 | San Ramon | 50 | D | 16 (10 health) |
| 33 | 94570 | Moraga | 45 | D | 18 (14 health) |
| 34 | 94575 | Moraga | 45 | D | 18 (14 health) |
Overview
California's 10th District encompasses 34 ZIP codes tracked by ZipCheckup. The district's average Home Safety Score is C (69/100).
161 EPA violations have been recorded across this district's water systems. 101 are health-based violations. About 65% of tracked ZIP codes have at least one violation.
Top Contaminants
The most frequently cited water quality issues in this district:
- Barium - 65 violations
- Stage 2 DBP Rule - 36 violations
- Stage 1 DBP Rule - 33 violations
- Combined Radium - 22 violations
- Consumer Confidence Report Rule - 3 violations
Housing Context
Homes in this district were built on average around 1977 (~49 years old). Older homes may have lead pipes or solder - consider a water filter if your home predates 1986.
Data Sources
- Water quality violations: EPA Safe Drinking Water Information System (SDWIS)
- Congressional district boundaries: U.S. Census Bureau, 119th Congress
- Housing age: U.S. Census Bureau American Community Survey
Updated daily. Data covers 34 ZIP codes in California's 10th District.