Mercer Island, WA Home Safety: Home Safety 100/100
1 ZIP code · 1 water system · Updated
ZipCheckup grade for Mercer Island: A.
Checked records flag no major concern; missing data is unknown.
Mercer Island, WA scores in the upper band of the ZipCheckup grade.
How Mercer Island Compares
Data: EPA SDWIS
Key Facts for Mercer Island Residents
- Homes built before 1986: 67% - older plumbing may contain lead solder.
- Health risk index (ZipCheckup composite of CDC data): 8.82.
Mercer Island's Water Providers
Only a single entry appears in the water system list for Mercer Island, WA; federal records tie 1 to the area.
- A
Overview
We track home safety data for 1 ZIP code in Mercer Island, Washington, covering 1 community water system serving approximately 25,282 people. The EPA snapshots used for this build directly map water systems to 1 of 1 ZIP codes.
The available EPA record reports 0 violations for 1 ZIP code with a reported violation count.
Home Safety Score
Average Home Safety Score for Mercer Island: A (100/100)
Model 4.0.0 uses four measured components across three equally weighted domains. If a required domain is unavailable, no score is published:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| PFAS MCL Screen | UCMR 5 testing against the covered federal MCLs |
| Radon Risk | EPA radon zone classification |
| Annual AQI | EPA AirData county-year median with at least 90 observed days |
Water Sources
Mercer Island water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Mercer Island
- Lead action-level status: not available
Radon Risk
1 of 1 ZIP records with known zones is in EPA Radon Zone 3.
The EPA recommends testing all homes regardless of radon zone. County radon zones cannot replace an in-home radon test.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 98040 | A | City of Mercer Island | 31,057 |
All ZIP Codes in Mercer Island
- 98040 [A]
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Reporting periods vary by source. Missing data is shown as unavailable, not as zero.
Mercer Island Community Health Snapshot
Source: CDC PLACES (County-level estimates). County health indicators are shown for context only and are not linked to this area's water records.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Mercer Island Infrastructure Age
With 67% of homes built before 1986, lead solder in plumbing is a potential concern. Federal law banned lead solder in drinking-water plumbing in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Renovation history matters as much as age: in Mercer Island, with a median build year of 1976, some older homes have been replumbed and some have not.
Over half of homes in Mercer Island were built before 1986, when federal law began restricting lead solder in drinking-water plumbing. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
Mercer Island: Lead Risk & Vulnerable Populations
Why children are most at risk: The CDC states that no safe blood lead level in children has been identified. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
If you have young children or are pregnant, consider testing your home's water - especially if your home was built before 1986.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Mercer Island: NFIP Claim Records and Water-Quality Context
Historical NFIP data for Mercer Island contains 13 flood insurance claims. Among claims with payment data, the average reported building, contents, and ICC component sum is $19,430. Among ZIP codes with claim records, 0% have an A- or V-family dominant rated zone recorded in those historical claims. This is not a complete current FEMA property-map inventory.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure.
Claim count does not establish current property risk. Check the exact address in FEMA's current map and obtain a property-specific insurance quote when relevant.
Source: historical FEMA National Flood Insurance Program (NFIP) claim records. No current FEMA property-map designation is asserted.
Deep Dive Reports
Detailed analysis for Mercer Island, WA