Waldo County, Maine
20 ZIP codes · Avg score 66/100 · Grade C · Updated 2026-06-03
Tracking 20 ZIP codes in Waldo County reveals a mixed picture — tap water quality varies meaningfully by location.
How Waldo County Compares
How Waldo County Compares
Waldo County scores 9 points above the Maine state average (57/100) and 2 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Waldo County, Maine
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 14 (asthma 13.1%, diabetes 11.7%)
Estimated additional annual cost per homeowner: $916, driven primarily by sea_level
Infrastructure: 0.365% avg pipe failure probability, 22% of ZIPs at high risk
54.3% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
→ Stable trendEPA violation counts by year across Waldo County water systems. Health-based shown in red, total in blue.
Peak year: 2023 with 9 violations. Past 5 years: 31 total (31 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: $916
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
22,698 housing units in Waldo 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 Waldo County
Remediation costs are relatively manageable for most homeowners in Waldo 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 Waldo 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 Waldo County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Black Horse Inn | 38 | 25 |
| 2 | UNITY BY THE STREAM LLC | 88 | 18 |
| 3 | Sandy Stream Village | 60 | 18 |
| 4 | School Street Village | 50 | 18 |
| 5 | Belfast Water District | 5,698 | 15 |
20 total water systems serve Waldo County.
All ZIP Codes in Waldo County
20 ZIP codes tracked in Waldo County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 4921 | Brooks | 83 | B | 1 | $193K |
| 2 | 4949 | Liberty | 83 | B | 1 | $224K |
| 3 | 4981 | Stockton Springs | 83 | B | 0 | $221K |
| 4 | 4952 | Morrill | 82 | B | 2 | $199K |
| 5 | 4974 | Searsport | 81 | B | 0 | $242K |
| 6 | 4915 | Belfast | 76 | B | 15 (2 health) | $262K |
| 7 | 4849 | Lincolnville | 72 | B | 10 | $317K |
| 8 | 4922 | Burnham | 72 | B | 8 | $150K |
| 9 | 4496 | Winterport | 66 | C | 6 (5 health) | $243K |
| 10 | 4346 | Randolph | 63 | C | 0 | $157K |
| 11 | 4848 | Islesboro | 63 | C | 0 | $291K |
| 12 | 4850 | Lincolnville Center | 63 | C | 0 | — |
| 13 | 4973 | Searsmont | 63 | C | 0 | $260K |
| 14 | 4988 | Unity | 58 | C | 18 (11 health) | $190K |
| 15 | 4354 | Palermo | 53 | D | 0 | $267K |
| 16 | 4847 | Hope | 53 | D | 0 | $302K |
| 17 | 4941 | Freedom | 53 | D | 0 | $193K |
| 18 | 4951 | Monroe | 53 | D | 0 | $215K |
| 19 | 4972 | Sandy Point | 53 | D | 0 | — |
| 20 | 4986 | Thorndike | 53 | D | 0 | $173K |
Recommended Buyer Guides for Waldo County
Eight risk categories drive the selection — PFAS exceedance, lead above EPA action level, pre-1978 housing share, EPA Radon Zone 1, flood-top-risk, wildfire-top-risk, multi-contaminant load, and a baseline fallback — and each category maps to a specific buyer-guide track that surfaces when the county data hits its threshold for that hazard signal.
- Best Lead Paint Test Kits — 54.3% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
Deep Dive Reports
Detailed analysis for Waldo County, Maine
Overview
Waldo County in Maine covers 20 ZIP codes with an average Home Safety Score of C (66/100).
8 of 20 ZIP codes have recorded EPA violations. 18 health-based violations have been documented.
← Back to Maine 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.