Rapid City Drinking Water Quality
What's Really in Your Tap Water?
Rapid City tap water has some quality concerns you should be aware of. At 615 ppm (36 gpg), the water is quite hard — you may notice mineral buildup on fixtures. Lead levels test well below the EPA action level. There have been 50 violations recorded over the past 3 years.
Some Concerns
Monitor recommended
36 GPG hardness
Lead
Below EPA action level
EPA action level: 15 ppb
Hardness
Very Hard water
US Average: 100 ppm
Is Rapid City Tap Water Safe to Drink?
Rapid City tap water has some quality concerns but remains within acceptable limits.
- •8 health-based violations in the past 3 years across 66 water systems.
- •Consider testing your water at home and using a certified water filter for added safety.
The data below shows test results from 66 water utilities serving 96K people in the Rapid City area. Water quality testing is conducted regularly and reported to the EPA.
How Hard is Rapid City Water?
615 ppm
36 grains per gallon
Very hard water causes significant mineral buildup. A water softener is recommended.
Impact on Your Home
Shower
Dries out skin & hair
Kitchen
Heavy mineral deposits
Laundry
Stiff, dingy clothes
Appliances
Significant scale
Regional Comparison
Values in ppm (mg/L as CaCO₃)
Based on 71 water samples from Pennington County.
Your pipes tell a different story
The data above shows what leaves the treatment plant—not what comes out of your faucet. Old pipes, lead solder, and building plumbing can add contaminants the city never tests for. Know exactly what's in your Rapid City tap water.
Home test kits detect lead, bacteria, pesticides, and 100+ other contaminants. Results in 5-10 business days from certified labs.
Lead & Contaminants
Understanding lead levels and water quality violations in Rapid City
Lead Test Results
90th Percentile Lead Level
5.21 ppb
Rapid City lead levels are well within safe limits.
Regular testing is still recommended, as lead can enter water through household plumbing.
Last sampled: 2024-12-31
About Lead in Drinking Water
What is Lead in Water?
Lead is a toxic metal that can dissolve into drinking water from older pipes, solder, and fixtures. It's invisible, tasteless, and odorless, making testing the only way to detect it. The EPA has set an action level of 15 ppb, though they emphasize there is no safe level of lead exposure.
Potential Health Effects
Developmental delays, learning difficulties, lower IQ, behavioral issues
High blood pressure, kidney damage, reproductive issues
How to Reduce Exposure
- •Run water for 30 seconds to 2 minutes before drinking, especially in the morning
- •Use cold water for cooking and drinking (hot water dissolves more lead)
- •Install a NSF-certified filter designed to remove lead
- •Test your water, especially if your home was built before 1986
EPA Compliance History
Action Recommended
Active health-based violations detectedConsider using a certified water filter until violations are resolved. Contact your utility for updates on corrective actions.
3-Year Violation Summary
50
Total Violations
8
Health-Related
42
Administrative
Health-Related Violations
Contaminant exceeded EPA safety limits. May require filter or alternative water source.
Administrative Violations
Missed testing deadlines or reporting. Does not indicate water quality issues.
Who Provides Rapid City's Water?
Utility Name
RAPID CITY
EPA System ID (PWSID)
SD4600406
Primary Water Source
Groundwater
Population Served
96K
Frequently Asked Questions
Common questions about Rapid City tap water quality
Nearby Cities in South Dakota
Sioux Falls
Very Hard water
Aberdeen
Very Hard water
Watertown
Pierre
Very Hard water
Brookings
Very Hard water
Mitchell
This data is for informational purposes only. Water quality can vary by neighborhood and building. For official reports, contact your local water utility or the EPA. Learn about our methodology