South Dakota tap water quality

510 community water systems serving 931,813 people.

Data: U.S. EPA · How we read the data · How we check it

systems with PFAS above a federal limit

people served by them

systems EPA tested for PFAS

systems above the lead action level

PFAS: EPA's 2023–2025 testing. Lead: results from the last five years. 2 more systems have no recent lead results in EPA's database.

Largest water systems in South Dakota

Sioux Falls Water System
216,462 people · Surface water · South Dakota
Lithium above screening level
Rapid City Water System
72,009 people · Surface water · South Dakota
PFHxS detected
Aberdeen Water System
27,989 people · Surface water · South Dakota
Lithium above screening levelAlso: 7 health-based violations since 2016
Brookings Municipal Utilities
23,377 people · Groundwater · South Dakota
Total trihalomethanes (TTHM) violationAlso: Lithium above screening level
Watertown Municipal Utilities
23,230 people · Groundwater · South Dakota
Total trihalomethanes (TTHM) violation
Web Water Development Association
20,750 people · Surface water · South Dakota
Lithium above screening level
Mitchell Water System
15,651 people · Purchased surface water · South Dakota
Lithium above screening level
Yankton Water System
15,411 people · Groundwater · South Dakota
Total trihalomethanes (TTHM) violationsAlso: Lithium above screening level
Huron Water System
14,263 people · Purchased surface water · South Dakota
Lithium above screening level
Pierre Water System
14,091 people · Surface water · South Dakota
Lithium above screening level
Box Elder Water System
14,000 people · Groundwater · South Dakota
Gross alpha violationsAlso: Radium (combined 226/228) violations
Spearfish Water System
13,803 people · Groundwater · South Dakota
No PFAS above limits
Minnehaha Community Water Corp
13,435 people · Groundwater · South Dakota
Lithium above screening level
By Water District
13,320 people · Surface water · South Dakota
Lithium above screening levelAlso: 2 health-based violations since 2016
Mid-Dakota Rural Water
11,833 people · Surface water · South Dakota
Lithium above screening level

South Dakota cities and towns

Most health-based violations since 2016

Meadow Crest Sanitary District
63 people · Groundwater · South Dakota
Gross alpha violationsAlso: Radium (combined 226/228) violations
Viewfield Rural Water System
220 people · Groundwater · South Dakota
Radium (combined 226/228) violationsAlso: Gross alpha violations
Cedar Gulch 2 Water System
40 people · Groundwater · South Dakota
Gross alpha violationsAlso: Radium (combined 226/228) violations
Owanka Rural Water System
52 people · Groundwater · South Dakota
Radium (combined 226/228) violations
Shirt Tail Gulch Development Water System
65 people · Groundwater · South Dakota
Gross alpha violationsAlso: Radium (combined 226/228) violations
Oak Mountain Country Estates Water System
85 people · Groundwater · South Dakota
Gross alpha violationsAlso: Radium (combined 226/228) violations
Golden Valley Water Company
283 people · Groundwater · South Dakota
Radium (combined 226/228) violationsAlso: Gross alpha violations
Box Elder Water System
14,000 people · Groundwater · South Dakota
Gross alpha violationsAlso: Radium (combined 226/228) violations
Provo Area Water System
25 people · Groundwater · South Dakota
Gross alpha violationsAlso: Radium (combined 226/228) violations
North Martin Water System
78 people · Purchased groundwater · South Dakota
Arsenic violations
Aberdeen Water System
27,989 people · Surface water · South Dakota
Lithium above screening levelAlso: 7 health-based violations since 2016
Walnut Park Water System
180 people · Groundwater · South Dakota
Not in EPA's PFAS sampleAlso: 7 health-based violations since 2016
Reynolds Court Water System
28 people · Groundwater · South Dakota
Not in EPA's PFAS sampleAlso: 6 health-based violations since 2016
Buffalo Gap Water System
126 people · Groundwater · South Dakota
Not in EPA's PFAS sampleAlso: 6 health-based violations since 2016
Springfield Water System
2,108 people · Surface water · South Dakota
Total trihalomethanes (TTHM) violations

All South Dakota utilities on this site

Every South Dakota system serving 50,000+ people or with PFAS above a federal limit, A to Z. Download all 510 systems as CSV.

Questions

Does South Dakota tap water have PFAS?

EPA tested 55 community water systems in South Dakota for 29 PFAS between 2023 and 2025. 2 had at least one regulated PFAS detected, and 0 had an entry-point average above a 2024 federal limit. Those 0 systems serve about 0 people. Systems have until 2029 to meet the limits.

How many South Dakota water systems have violations?

182 systems in South Dakota had at least one health-based violation since 2016 (464 violations in total). 34 violations are currently listed as unaddressed.

Which South Dakota water systems are over the lead action level?

0 systems had a lead 90th percentile above the 15 ppb action level in their most recent results from the last five years. Another 2 systems have no lead results in EPA's database from the last five years. Lead depends on each home's pipes, so a test of your own tap is the only way to know your level.

Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.