Interior, SD Water Safety: 53/100 (2026)
1 ZIP code · 1 water system · Updated 2026-06-03
Within Interior, water quality data indicates below-average safety by SD standards — independent testing is a reasonable precaution for residents whose systems show active violations.
How Interior Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Interior Water
- Homes built before 1986: 67% — older plumbing may contain lead solder.
- Estimated remediation: $400 per household.
- CDC health risk index: 17.66 — above typical levels.
Who Supplies Your Water in Interior
Federal records track 1 water system in Interior, SD, and a single provider handles the dominant share of residential connections while carrying primary responsibility for EPA compliance.
Overview
We track water quality and home safety data for 1 ZIP code in Interior, South Dakota (population ~286), covering 1 community water system serving approximately 699 people region-wide.
No EPA violations recorded across any ZIP codes in Interior — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Interior: D (53/100)
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
Interior water systems draw from: Groundwater.
Lead & Copper
- Lead data: not yet available for Interior
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate 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 |
|---|---|---|---|
| 57750 | D | WALL | 699 |
All ZIP Codes in Interior
- 57750 [D]
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 Interior
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 Interior
With 67% 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
Housing age is one of the most reliable proxies for plumbing-era lead risk, because two federal milestones — the widespread use of lead pipes before 1970 and the continued use of lead solder until 1986 — define the highest-risk tiers of the residential housing stock. With a median build year of 1976, Interior falls squarely within the older range — meaning a large fraction of the housing was built under the plumbing standards of those earlier eras. The distribution above captures where that risk concentrates, and why older neighborhoods warrant particular attention from residents concerned about tap water quality.
Over half of homes in Interior 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.
Lead Exposure Risk for Children in Interior
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.
67% — that captures the slice of Interior housing dating from before the federal ban on solder containing lead. It pairs with aggregate utility readings that either approach or cross 0.015 mg/L, the benchmark set under the EPA Lead and Copper Rule. Together, the two figures shift one-home reads into a standard household-level confirmation, particularly for families with kids. A certified lead-removal filter is available through retailer-verified channels if a kit returns results that warrant additional measures.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
What You Can Do in Interior
- 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 67% of homes built before 1986, lead solder is a real possibility.
- Review your water system's CCR. Your utility publishes an annual Consumer Confidence Report with detailed test results. Request it or find it online.
Deep Dive Reports
Detailed analysis for Interior, SD