Rapid City, SD Water Safety: 77/100 (2026)
4 ZIP codes · 14 water systems · Updated 2026-06-03
EPA compliance records for Rapid City 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 SD.
How Rapid City Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Rapid City Water
- Average lead level: 0.006 mg/L.
- Homes built before 1986: 53% — older plumbing may contain lead solder.
- Estimated remediation: $1,575 per household.
- CDC health risk index: 12.98 — above typical levels.
Who Supplies Your Water in Rapid City
Federal drinking water records identify 14 systems in Rapid City, SD. The leading 3 providers serve the largest share of residential connections, each operating as a separate entity with its own rate authority, infrastructure management, and EPA compliance obligations — so service conditions are not uniform city-wide.
Overview
We track water quality and home safety data for 4 ZIP codes in Rapid City, South Dakota, covering 14 community water systems serving approximately 98,535 people.
No EPA violations recorded across any ZIP codes in Rapid City — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Rapid City: B (77/100)
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
Rapid City water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0060 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 4 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 57701 | B | Rapid City | 72,009 |
| 57702 | B | Rapid City | 72,009 |
| 57703 | B | Rapid City | 72,009 |
| 57709 | B | Rapid City | 72,009 |
All ZIP Codes in Rapid City
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 Rapid City
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 Rapid City
With 53% 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
What does a median build year of 1980 mean for water safety in Rapid City? It means the majority of the city's residential plumbing was installed before 1986, when lead solder was federally banned, and a large share may predate 1970, when lead pipes were commonly used — making plumbing age a central variable in household-level lead risk across much of the city.
Over half of homes in Rapid City 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 Rapid City Homeowners
Placing remediation in the context of Rapid City's property market, the equity share is low — most homeowners here are weighing a financial commitment that fits comfortably within routine property planning, far from the threshold where remediation becomes a material equity decision rather than a standard upkeep consideration.
Remediation costs in Rapid City are relatively low compared to home values. The $775–$2,550 estimated range is a small fraction of median property value. Home values are 43% above the South Dakota average.
Lead Exposure Risk for Children in Rapid City
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 53% of the Rapid City inventory comes from before the federal ban on lead-bearing solder — and if utility samples sit at or near 0.015 mg/L — the gap between citywide averages and one specific faucet becomes a practical concern rather than a theoretical one. That is why one-home reads exist as a separate measurement. A certified filter through retailer networks addresses confirmed exposure where it appears in a household.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Rapid City
FEMA data shows 75% of Rapid City's ZIP codes mapped into designated flood zones, paired with an NFIP record of 94 claims. That footprint places local flood exposure in the range where it warrants attention without rising to high-severity planning territory.
Rapid City has a moderate flood history with 94 FEMA claims averaging $4,671 per payout. 75% 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>$1,575</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 Rapid City, SD