Clark Fork, ID: High Radon Risk — 66/100 (2026)
1 ZIP code · 1 water system · Updated 2026-06-03
Clark Fork shows moderate tap water quality for ID — some areas carry documented EPA violations while others meet standards without issues.
How Clark Fork Compares
Data: EPA SDWIS Last verified: 2026-06-03
Clark Fork Water: The Quick Version
- Average lead level: 0.002 mg/L.
- Homes built before 1986: 59% — older plumbing may contain lead solder.
- Estimated remediation: $1,200 per household.
- CDC health risk index: 13.49 — above typical levels.
Water Systems Serving Clark Fork
Clark Fork, ID draws its water from one primary utility across 1 tracked system.
Overview
We track water quality and home safety data for 1 ZIP code in Clark Fork, Idaho, covering 1 community water system serving approximately 1,660 people.
No EPA violations recorded across any ZIP codes in Clark Fork — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Clark Fork: C (66/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Clark Fork water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0020 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 83811 | C | City of Clark Fork | 730 |
All ZIP Codes in Clark Fork
- 83811 [C]
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
Updated daily.
CDC Health Data for Clark Fork
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
How Old Is Clark Fork's Housing Stock?
With 59% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Reading the housing age data for Clark Fork — median build year 1972 — the overriding implication is that the plumbing materials inside a typical home here reflect pre-1986 construction standards. In practical terms, that means lead-soldered copper joints are common across much of the housing stock. Where those materials are present, water can leach lead as it moves through joints — a pathway that corrosion control treatment under federal rules is designed to reduce, though it cannot eliminate lead risk where the plumbing materials themselves contain lead.
Over half of homes in Clark Fork were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
Clark Fork: Remediation Cost in Perspective
When estimated remediation is placed alongside median property values in Clark Fork, the resulting ratio is low — a finding consistent with a household financial perspective where documented issues can be addressed without a meaningful impact on overall equity position, making this market one of the more favorable contexts for remediation planning.
Remediation costs in Clark Fork are relatively low compared to home values. The $800–$1,500 estimated range is a small fraction of median property value. Home values are 29% below the Idaho average.
Protecting Children from Lead in Clark Fork
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Pulling a tap sample fills the gap that utility data cannot close, particularly here where 59% of housing dates from the pre-rule era and citywide monitoring sits at or above the regulatory mark in Clark Fork.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
What You Can Do in Clark Fork
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. With 59% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Clark Fork, ID