Big Lake, MN: High Radon Risk — 70/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-03
In current MN EPA data, Big Lake's tap water sits in the high-safety tier.
How Big Lake Compares
Data: EPA SDWIS Last verified: 2026-06-03
Big Lake Water: The Quick Version
- Average lead level: 0.001 mg/L.
- Homes built before 1986: 27% — older plumbing may contain lead solder.
- Estimated remediation: $2,900 per household.
- CDC health risk index: 11.68.
Water Systems Serving Big Lake
Water supply in Big Lake, MN follows a divided structure: 2 utilities account for the largest share of residential service out of 2 total systems, each managing its own distribution network and EPA reporting. Because these systems operate independently, rate decisions and compliance outcomes are determined separately.
Overview
We track water quality and home safety data for 1 ZIP code in Big Lake, Minnesota, covering 2 community water systems serving approximately 21,406 people.
No EPA violations recorded across any ZIP codes in Big Lake — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Big Lake: 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
Big Lake water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0010 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 |
|---|---|---|---|
| 55309 | B | Big Lake | 12,413 |
All ZIP Codes in Big Lake
- 55309 [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.
CDC Health Data for Big Lake
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 Big Lake's Housing Stock?
Housing age data helps assess potential lead pipe and infrastructure risks. Newer housing stock generally means lower plumbing-related contamination risk.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Since 1986, federal law has prohibited lead solder in new residential plumbing. With a median build year of 1993, much of Big Lake's housing falls on the safer side of that line — though homes built before 1986 still warrant testing regardless of the city-wide profile.
Most homes in Big Lake were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.
Source: U.S. Census Bureau ACS B25034.
Big Lake: Remediation Cost in Perspective
Property equity in Big Lake runs well ahead of estimated remediation costs — a cost-to-value ratio that sits in the low tier, meaning documented water and safety issues here are the kind homeowners can plan to address without treating the expense as a significant budget event relative to what their homes are worth.
Remediation costs in Big Lake are relatively low compared to home values. The $1,900–$4,100 estimated range is a small fraction of median property value. Home values are 40% above the Minnesota average.
Protecting Children from Lead in Big Lake
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.
Through the multi-year window of EPA Lead and Copper Rule monitoring, Big Lake has stayed under the action mark. Paired with a 27% pre-rule housing share, the result places lead in a lower-priority spot on the local picture — without erasing the structural gap between citywide averages and what arrives at one specific tap.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Big Lake
A moderate NFIP record for Big Lake — 2 insurance claims paired with 100% of ZIP codes in FEMA flood zones — points to a flood history where water-quality pathways have likely been periodically relevant.
Big Lake has a moderate flood history with 2 FEMA claims averaging $2,049 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>$2,900</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 Big Lake, MN