De Smet, SD: High Radon Risk — 70/100 (2026)
1 ZIP code · 4 water systems · Updated 2026-06-03
De Smet's tap water quality puts it in SD's upper tier — health-based violations are rare and the compliance record is consistently above average.
How De Smet Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About De Smet Water
- Average lead level: 0.001 mg/L.
- Homes built before 1986: 71% — older plumbing may contain lead solder.
- Estimated remediation: $2,400 per household.
- CDC health risk index: 13.61 — above typical levels.
Who Supplies Your Water in De Smet
De Smet, SD is covered by 3 major water utilities out of 4 federally tracked systems, each managing its own pipes, treatment processes, and EPA filings. What a household gets from the tap depends on which provider's system serves that address.
Overview
We track water quality and home safety data for 1 ZIP code in De Smet, South Dakota (population ~1,769), covering 4 community water systems serving approximately 22,059 people region-wide.
No EPA violations recorded across any ZIP codes in De Smet — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for De Smet: 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
De Smet 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 |
|---|---|---|---|
| 57231 | B | Mid-dakota Rural Water | 11,833 |
All ZIP Codes in De Smet
- 57231 [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 De Smet
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 De Smet
With 71% 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 1963, as in De Smet, 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 De Smet 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 De Smet Homeowners
How does remediation fit within the broader financial picture for De Smet homeowners? The equity share is moderate — large enough that treating it as a real planning consideration makes sense, and manageable enough that most homeowners have a clear path to addressing documented water and safety issues when they approach the commitment with deliberate advance budgeting rather than as an unplanned expense.
Remediation costs are moderate relative to home values in De Smet. The estimated $1,600–$3,300 range is manageable for most homeowners but still worth budgeting for. Home values are 1% below the South Dakota average.
Lead Exposure Risk for Children in De Smet
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.
When older housing represents 71% of the local inventory or aggregate readings approach the federal action level, an in-home check becomes the standard way to translate citywide averages into the specific reality of an individual De Smet address.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in De Smet
The National Flood Insurance Program captures decades of claims at the local level, building a record of cumulative community flood exposure. For De Smet, that record documents 7 claims and 100% of ZIP codes inside FEMA-designated flood zones. What makes those numbers relevant to water quality is the set of mechanisms flooding activates: heavy precipitation that floods treatment intake zones can introduce contaminants upstream of normal filtration; well casings in low-lying areas can be infiltrated by floodwaters carrying bacteria, sediment, and chemical residue; and distribution system pressure changes during flooding can create backflow conditions. These effects become more probable as flood frequency and magnitude increase — and the NFIP record indicates both are meaningful factors locally.
De Smet has a moderate flood history with 7 FEMA claims averaging $8,160 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 De Smet, SD