Colwell, IA: High Radon Risk — 66/100 (2026)
1 ZIP code · 1 water system · Updated 2026-06-03
Across water systems in Colwell, safety results are uneven — a portion carry active or recent violations, while others meet federal standards without incident, placing the city in the middle tier for IA.
How Colwell Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Colwell Residents
- Average lead level: 0.0032 mg/L.
- Homes built before 1986: 86% — older plumbing may contain lead solder.
- Estimated remediation: $1,200 per household.
- CDC health risk index: 14.46 — above typical levels.
Colwell's Water Providers
Across most of Colwell, IA, residential water comes from a single utility. That provider sets rates, manages infrastructure maintenance, and files compliance reports with the EPA on behalf of the households it serves. Federal tracking data shows 1 system on record, but one carries the bulk of the service load.
Overview
We track water quality and home safety data for 1 ZIP code in Colwell, Iowa, covering 1 community water system serving approximately 54 people.
No EPA violations recorded across any ZIP codes in Colwell — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Colwell: 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
Colwell water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0032 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 |
|---|---|---|---|
| 50620 | C | City of Colwell, | 55 |
All ZIP Codes in Colwell
- 50620 [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.
Colwell Community Health Snapshot
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
Colwell Infrastructure Age
With 86% 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
Colwell's housing stock is predominantly older, with a median build year of 1948 that reflects decades of construction before federal plumbing standards were tightened. The 1986 ban on lead solder and the pre-1970 era of lead service lines are both relevant benchmarks here — a significant share of the residential inventory predates one or both of those cutoffs, creating an elevated baseline for plumbing-related lead risk that aggregate water quality data may not fully reflect at the household level.
Over half of homes in Colwell 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.
How Remediation Costs Compare in Colwell
Across the Colwell housing market, the estimated remediation share lands in a middle tier — not a minor footnote, but not a prohibitive burden either; the cost-to-value ratio reflects a moderate equity commitment, one that sits above routine maintenance territory and warrants a dedicated line in the household budget.
Remediation costs are moderate relative to home values in Colwell. The estimated $800–$1,500 range is manageable for most homeowners but still worth budgeting for. Home values are 36% below the Iowa average.
Colwell: Lead Risk & Vulnerable Populations
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.
Before the federal solder ban, lead solder was a routine plumbing material, and 86% of the Colwell inventory was built in that earlier era — a share large enough to move household-level reads onto the standard list.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
What You Can Do in Colwell
- 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 86% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Colwell, IA