WaterVerge

Is Rapid City, SD Tap Water Safe to Drink?

Graded B, with 16 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

808 residents served 3 water systems PWSID: SD4600014
Overall Score
75 / 100
Violations
16 active
Last Updated
May 2026
Source
Groundwater
#113 of 141 in South Dakota Top 62% nationally
Private
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
BGRADE
Water Quality Grade
75/100
waterverge.com
B 75/100

Rapid City, SD — Water Quality Report

Rapid City's drinking water received a grade of B (75 out of 100), indicating good water quality. The city's 3 water systems serve approximately 808 residents using groundwater.

Lead levels were measured at 1.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.

The system has 289 violations on record, including 13 health-based violations. 16 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Rapid City's water

Rapid City ranks #113 out of 141 cities in South Dakota for water quality, placing it among the lowest-rated in the state.

Rapid City relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

As a small community water system, Rapid City may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
75 out of 100 Grade B
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
25/45
D
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 1.0 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Rapid City, SD water safe to drink?

Concerns Identified

Rapid City's drinking water has significant quality concerns based on EPA testing data. With a grade of B (75/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 808 residents using groundwater (wells).

16
Active Violations
1.0 ppb
Lead (90th %ile)
7 events
Disaster History

Recent water quality updates for Rapid City

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Rapid City's water quality assessment. Grade: B (75/100).

Violation
2 drinking water violations recorded

2 health-based. Contaminants: Groundwater Rule.

Disaster
SEVERE STORMS AND FLOODING

Federal disaster declaration (FEMA DR-4463). Flood event — may have impacted local water infrastructure.

Disaster
SEVERE WINTER STORM, SNOWSTORM, AND FLOODING

Federal disaster declaration (FEMA DR-4440). Flood event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Groundwater Rule.

Violation
2 drinking water violations recorded

Contaminants: Chlorine.

Key contaminant findings

Based on the most recent EPA sampling data for Rapid City's water supply.

Lead Within Limits
Detected: 1.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Rapid City's water system has 289 total violations on record, including 13 health-based violations. 16 remain unresolved.

TTMRMCLOther
Most recent violations:
Oct 2019 Groundwater Rule Open
Oct 2019 Groundwater Rule Open
Nov 2018 Groundwater Rule Open
Jan 2016 Chlorine Resolved
Jan 2016 Chlorine Resolved

Flood & environmental risk

Pennington County has experienced 7 federally declared disasters since 1965. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Spring Creek, Rapid Creek, Wild Irishman Gulch, Cleghorn Springs, South Canyon.

SEVERE STORMS AND FLOODING
Flood FEMA DR-4463
SEVERE WINTER STORM, SNOWSTORM, AND FLOODING
Flood FEMA DR-4440
HURRICANE KATRINA EVACUATION
Coastal Storm FEMA DR-3234

Where does Rapid City's water come from?

Rapid City's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 808 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Spring Creek (river), Rapid Creek (river), Wild Irishman Gulch (river), Cleghorn Springs (river), South Canyon (river).

What Rapid City residents can do

Install a water filter

Recommended: NSF-certified water filter. This addresses the specific contaminants found in Rapid City's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Monitor alerts during storms

Rapid City's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
1.0 ppb
EPA Action Level: 15 ppb · 7% of limit
Safe Level
Compliance Record

Violation summary

289
Total violations
13
Health-based
16
Active / unresolved
Oct 2019
Most recent violation
Compliance Record

Violations & advisories

289 Total
16 Active
13 Health-based
273 Resolved
Violations by category
Volatile Organic Chemicals
147
Synthetic Organic Chemicals
64
Total Coliform Rule
15
Stage 1 Disinfectants and Disinfection Byproducts Rule
12
Radionuclides and Revised Rad Rule
12
Oct 2019 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Oct 2019 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Nov 2018 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Feb 2015 Active
Stage 1 Disinfectants and Disinfection Byproducts Rule
Treatment Technique
Health-Based Health 0
Feb 2015 Active
Stage 1 Disinfectants and Disinfection Byproducts Rule
Treatment Technique
Health-Based Health 0
Mar 2011 Active
Stage 1 Disinfectants and Disinfection Byproducts Rule
Treatment Technique
Health-Based Health 0
Mar 2011 Active
Stage 1 Disinfectants and Disinfection Byproducts Rule
Treatment Technique
Health-Based Health 0
Jan 2009 Active
Stage 1 Disinfectants and Disinfection Byproducts Rule
Treatment Technique
Health-Based Health 0
Jan 2009 Active
Stage 1 Disinfectants and Disinfection Byproducts Rule
Treatment Technique
Health-Based Health 0
Sep 2003 Active
Public Notice
Other Violation 0
Jul 2002 Active
Consumer Confidence Rule
Other Violation 0
Jul 2002 Active
Consumer Confidence Rule
Other Violation 0
Jul 2002 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Jan 2016 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2016
Jan 2016 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2016
Oct 2015 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2015
Oct 2015 Resolved
Chlorine
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2015
Showing 20 of 289 violations
Industrial pollution

Top industrial polluters within 10 miles of Rapid City

Industrial polluters nearby

Reported releases to surface water by facilities near Rapid City, ranked by pounds discharged annually.

FacilityTop chemicalTo surface water (lbs/yr)Distance
FOREST PRODUCTS DISTRIBUTORS INC
Wood Products · NA
RAPID CITY, SD57703
2.9 mi
HUBBARD FEEDS INC
Food · ALLTECH INC
RAPID CITY, SD57701
0.9 mi
PETE LIEN & SONS INC
Nonmetallic Mineral Product · PETE LIEN & SONS INC
RAPID CITY, SD57702
5.5 mi
GCC DACOTAH
Nonmetallic Mineral Product · GCC OF AMERICA
RAPID CITY, SD57702
2.8 mi
U.S. DOD USAF, ELLSWORTH AFB
Other · US DEPARTMENT OF DEFENSE
ELLSWORTH AFB, SD57706
8.7 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Rapid City

Superfund sites nearby

Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.

Source: EPA Superfund National Priorities List

Environmental Risk

Drought conditions

D3 — extreme drought

Pennington County is currently in D3 (extreme drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

10
Weeks at D2+ (current streak)
23.7%
Months in D2+ (last 30y)
10
Weeks at D2+ (last 5y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

7
Declared disasters
Sep 2019
Most recent
Flood
Most common type

Pennington County has experienced 7 federally declared disasters since 1965. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2019
SEVERE STORMS AND FLOODING
Flood FEMA #4463
Jun 2019
SEVERE WINTER STORM, SNOWSTORM, AND FLOODING
Flood FEMA #4440
Sep 2005
HURRICANE KATRINA EVACUATION
Coastal Storm FEMA #3234
Apr 1997
SEVERE FLOODING, SEVER WINTER STORMS,HEAVY RAINS HIGH WINDS
Flood FEMA #1173
May 1995
FLOODING
Flood FEMA #1052
Jun 1972
HEAVY RAINS & FLOODING
Flood FEMA #336

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 1.0 15 ppb Inorganic Safe
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 2.0 ppb from 1993 (3.0 ppb) to 2025 (1.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Private
Population Served
808
Water Systems
3
Water Source

Where Rapid City's water comes from

Groundwater

Rapid City's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by private ownership and serves approximately 808 people through 3 water systems.

Local Hydrology

Water bodies near Rapid City

Rapid City is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Spring Creek
river
Rapid Creek
river
Wild Irishman Gulch
river
Cleghorn Springs
river
South Canyon
river
Infrastructure

Water systems serving Rapid City

System Name PWSID Population Source
PRAIRIE ACRES LLC SD4600014 350 GW
PRAIRIE ACRES NORTH SD4600884 288 GW
PRAIRIE ACRES SOUTH SD4600428 170 GW
Regional Comparison

How Rapid City compares

Full South Dakota rankings →

Rapid City's score of 75/100 is above the average of 66/100 among major South Dakota cities. It outscores 6 of 10 nearby cities.

Rapid City (this city)
75
Rapid City
38.7
Aberdeen
41.8
Pierre
87.3
South Dakota avg
66
City Profile

About Rapid City, SD

Wikipedia →

Rapid City is a city in and the county seat of Pennington County, South Dakota, United States. It is located on the eastern slope of the Black Hills in western South Dakota and was named after Rapid Creek, where the settlement developed. It is the second-most populous city in the state with a population of 74,703 as of the 2020 census. The Rapid City metropolitan area has 156,000 residents.

Economic Profile
$62,784
Median Income
$243,577
Median Home Value
$975/mo
Median Rent
3.4%
Unemployment
Community
38.6
Median Age
530
People / sq mi
35.5%
College Educated
61.7%
Homeownership
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Frequently asked questions

Is Rapid City, SD tap water safe to drink?

Rapid City's water quality earned a grade of B (75/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #113 out of 141 cities tested in South Dakota.

What contaminants are in Rapid City's water?

Lead was measured at 1.0 ppb (90th percentile). 289 violations are on record.

How is Rapid City's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Rapid City?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Rapid City's water come from?

Rapid City's water is sourced from Groundwater. The city has 3 water systems serving approximately 808 residents.

What health violations has Rapid City's water system had?

Rapid City has 13 health-based violations on record. The most recent violation was recorded in October 2019. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 16 violations remain unresolved.

Is Rapid City's groundwater at risk of contamination?

Rapid City uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 289 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does Rapid City's water compare to other cities?

Rapid City ranks #113 out of 141 cities in South Dakota (better than 20% of state cities) and #9709 out of 15744 cities nationally (38th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.