Yakima County, Washington
26 ZIP codes · Avg score 71/100 · Grade B · Updated 2026-06-03
The 26 water systems serving Yakima County show strong compliance with federal drinking water standards.
How Yakima County Compares
How Yakima County Compares
Yakima County scores 7 points below the Washington state average (78/100) and 3 points above the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Yakima County, Washington
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 12.9 (asthma 10.7%, diabetes 12.9%)
Estimated additional annual cost per homeowner: $3,079, driven primarily by wildfire
Infrastructure: 0.397% avg pipe failure probability, 40% of ZIPs at high risk
64% of homes built before 1978 (lead paint era)
Violation History (2021–2024)
→ Stable trendEPA violation counts by year across Yakima County water systems. Health-based shown in red, total in blue.
Peak year: 2023 with 13 violations. Past 5 years: 17 total (17 health-based).
Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.
County Health Indicators vs National Average
Black markers indicate national averages. Source: CDC PLACES, Census ACS.
Infrastructure Overview
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $3,079
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
91,375 housing units in Yakima County
Source: U.S. Census Bureau ACS B25034 (Year Structure Built).
Water Safety Affordability
How much it costs to fix water issues relative to home values in Yakima County
Remediation costs are relatively manageable for most homeowners in Yakima County, representing a small fraction of property value.
Remediation includes water filtration, lead abatement, radon mitigation, and flood protection where applicable. Source: Census ACS, EPA SDWIS.
Health Outcomes vs National Average
CDC PLACES data for Yakima County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water Systems with Most Violations
Top 5 systems in Yakima County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Yak Company - Terrace Heights | 8,410 | 51 |
| 2 | City of Yakima Water Division | 112,858 | 39 |
| 3 | Nob Hill Water Association | 36,026 | 35 |
| 4 | Snake River Housing Water System | 3,036 | 35 |
| 5 | City of Tieton Water Department | 1,475 | 35 |
24 total water systems serve Yakima County.
All ZIP Codes in Yakima County
26 ZIP codes tracked in Yakima County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 98932 | Granger | 83 | B | 1 | $230K |
| 2 | 98902 | Yakima | 82 | B | 5 (1 health) | $238K |
| 3 | 98904 | Yakima | 82 | B | 5 (1 health) | — |
| 4 | 98907 | Yakima | 82 | B | 5 (1 health) | — |
| 5 | 98909 | Yakima | 82 | B | 5 (1 health) | — |
| 6 | 98935 | Mabton | 82 | B | 2 | $196K |
| 7 | 98944 | Sunnyside | 82 | B | 2 | $230K |
| 8 | 98953 | Zillah | 82 | B | 3 (1 health) | $363K |
| 9 | 98930 | Grandview | 81 | B | 8 (2 health) | $278K |
| 10 | 98936 | Moxee | 80 | B | 3 | $325K |
| 11 | 98933 | Harrah | 79 | B | 2 | $225K |
| 12 | 98901 | Yakima | 77 | B | 5 (1 health) | $268K |
| 13 | 98942 | Selah | 77 | B | 2 (1 health) | $352K |
| 14 | 98948 | Toppenish | 73 | B | 15 | $218K |
| 15 | 98903 | Yakima | 72 | B | 5 (1 health) | $266K |
| 16 | 98908 | Yakima | 72 | B | 5 (1 health) | $357K |
| 17 | 98937 | Naches | 71 | B | 2 | $343K |
| 18 | 98951 | Wapato | 67 | C | 13 | $214K |
| 19 | 98923 | Cowiche | 63 | C | 0 | $228K |
| 20 | 98947 | Tieton | 63 | C | 0 | $240K |
| 21 | 98920 | Brownstown | 53 | D | 0 | — |
| 22 | 98921 | Buena | 53 | D | 0 | — |
| 23 | 98938 | Outlook | 53 | D | 0 | $174K |
| 24 | 98939 | Parker | 53 | D | 0 | — |
| 25 | 98952 | White Swan | 53 | D | 0 | $111K |
| 26 | 99322 | Bickleton | 53 | D | 0 | — |
Recommended Buyer Guides for Yakima County
If FEMA records flag flood-top-risk status or EPA samples show PFAS exceedances, the matching logic lifts emergency-water and PFAS-rated filtration into the recommendations — federal data drives the order, not retailer arrangements.
- Best Lead Paint Test Kits — 64% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best HEPA Air Purifiers for Wildfire Smoke — Wildfire is the top compound risk factor
Deep Dive Reports
Detailed analysis for Yakima County, Washington
Overview
Yakima County in Washington covers 26 ZIP codes with an average Home Safety Score of B (71/100).
18 of 26 ZIP codes have recorded EPA violations. 11 health-based violations have been documented.
← Back to Washington water quality report
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Updated daily.