Winthrop, IA: High Radon Risk — 70/100 (2026)
1 ZIP code · 1 water system · Updated 2026-06-03
EPA compliance records for Winthrop tell a largely clear story: violation rates are low, health-based exceedances are uncommon, and the city's grade puts it well above average within IA.
How Winthrop Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Winthrop Water
- Average lead level: 0.0035 mg/L.
- Homes built before 1986: 74% — older plumbing may contain lead solder.
- Estimated remediation: $2,400 per household.
- CDC health risk index: 13.3 — above typical levels.
Who Supplies Your Water in Winthrop
The structure of water supply in Winthrop, IA is straightforward: one utility provides the bulk of residential service among 1 tracked system, concentrating rate-setting and infrastructure decisions under a single organization.
Overview
We track water quality and home safety data for 1 ZIP code in Winthrop, Iowa, covering 1 community water system serving approximately 1,700 people.
No EPA violations recorded across any ZIP codes in Winthrop — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Winthrop: B (70/100)
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
Winthrop water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0035 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 |
|---|---|---|---|
| 50682 | B | Winthrop Water Supply | 840 |
All ZIP Codes in Winthrop
- 50682 [B]
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.
Health Outcomes in Winthrop
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
Housing & Infrastructure in Winthrop
With 74% 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
When a city's housing median build year is 1960, as in Winthrop, the implication for water quality research is straightforward: municipal-level data captures what leaves the treatment plant, but household plumbing from before 1986 determines what actually arrives at the tap. In cities where older housing predominates, that gap between system-level and household-level data is widest.
Over half of homes in Winthrop 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.
Cost Context: What Remediation Means for Winthrop Homeowners
The equity-to-remediation ratio in Winthrop is moderate — worth planning for but within reach for most property owners.
Remediation costs are moderate relative to home values in Winthrop. The estimated $1,600–$3,300 range is manageable for most homeowners but still worth budgeting for. Home values are 10% above the Iowa average.
Lead Exposure Risk for Children in Winthrop
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.
After the federal action removing lead-bearing solder from new plumbing took effect, building practice shifted — but 74% of the Winthrop inventory predates that line. With aggregate samples near or beyond 0.015 mg/L, an in-home check moves out of the optional column into the standard list.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Winthrop
Measured across the NFIP's multi-decade tracking period, Winthrop shows a moderate flood record — 4 claims and 100% of ZIP codes carrying FEMA flood zone status. For water quality, that combination matters because flood events at this frequency can periodically stress infrastructure: treatment plants, private wells, and distribution systems all face elevated risk during significant flooding.
Winthrop has a moderate flood history with 4 FEMA claims averaging $3,463 per payout. 100% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
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. Flood damage can add significantly to the estimated <strong>$2,400</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
Deep Dive Reports
Detailed analysis for Winthrop, IA