North Sioux City, SD: High Radon Risk — 55/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-04
Compliance figures for North Sioux City indicate average water quality in SD overall — some service areas have recorded health-based violations in recent monitoring cycles, while others operate cleanly, making system-level data the most actionable reference point for residents.
How North Sioux City Compares
Data: EPA SDWIS Last verified: 2026-06-04
Key Facts for North Sioux City Residents
- Average lead level: 0.004 mg/L.
- Homes built before 1986: 21% — older plumbing may contain lead solder.
- Estimated remediation: $2,400 per household.
- CDC health risk index: 11.98.
North Sioux City's Water Providers
Across North Sioux City, SD, residential water comes from 2 primary utilities rather than a single consolidated provider. Each system operates independently — managing its own distribution infrastructure, rate schedules, and EPA compliance filings. Federal records track 2 water systems in the area, with these top providers accounting for the majority of residential connections.
Overview
We track water quality and home safety data for 1 ZIP code in North Sioux City, South Dakota, covering 2 community water systems serving approximately 7,814 people.
No EPA violations recorded across any ZIP codes in North Sioux City — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for North Sioux City: C (55/100)
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
North Sioux City water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0040 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 |
|---|---|---|---|
| 57049 | C | North Sioux City | 3,042 |
All ZIP Codes in North Sioux City
- 57049 [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.
North Sioux City 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
North Sioux City Infrastructure Age
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
The median home in North Sioux City was built in 2008, after the federal ban on lead solder in plumbing. Most of the housing stock postdates that cutoff, placing typical plumbing risk on the lower end — though any home built before 1986 still warrants individual testing.
Most homes in North Sioux City 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.
How Remediation Costs Compare in North Sioux City
Across North Sioux City, the equity share taken up by estimated remediation is small — a favorable ratio for most property owners.
Remediation costs in North Sioux City are relatively low compared to home values. The $1,600–$3,300 estimated range is a small fraction of median property value. Home values are 133% above the South Dakota average.
North Sioux City: 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.
If aggregate samples sit below the EPA action level and just 21% of North Sioux City's inventory comes from the pre-rule era, systemic lead is not a dominant local concern. The aggregate still cannot tell a homeowner what is actually flowing from a specific faucet on a specific morning, which is why an in-home draw exists as a separate measurement at the household tier.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
North Sioux City: Flood History & Water Damage Risk
How does North Sioux City's flood record connect to local water quality? The NFIP documents 362 claims — enough to signal recurring events — and 100% of ZIP codes carry FEMA flood zone status. That combination places flooding in the category of factors that can periodically affect water infrastructure, even if the area isn't among the highest-exposure communities in the NFIP dataset.
North Sioux City has a moderate flood history with 362 FEMA claims averaging $16,286 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.
What You Can Do in North Sioux City
- 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. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for North Sioux City, SD