PFAS Testing Results
South Dakota
PFAS testing results for 49 water systems serving 684,666 residents.
2 systems exceed federal PFAS limits, affecting 15,508 residents.
Systems tested
49
14.3% had PFAS detections
Limits exceeded
2
4.1% of systems
Population affected
16K
served by systems over federal limits
Most common compound
11Cl-PF3OUdS
detected in 7 systems
Grade distribution
Every water system gets a letter grade based on how its worst detected PFAS compound compares to the federal Maximum Contaminant Level. Lower grades mean higher contamination.
Communities exceeding federal limits
The water systems in South Dakota where at least one PFAS compound exceeds the EPA Maximum Contaminant Level, sorted worst first.
| System name | City | Grade | Worst compound | Times over limit | Population |
|---|---|---|---|---|---|
| NPS-MOUNT RUSHMORE NATIONAL MEMORIAL | KEYSTONE | D | PFOS | 2.5x | 4.1K |
| RAPID VALLEY SANITARY DISTRICT | RAPID CITY | D | PFOS | 1.4x | 11K |
Resources for taking action are available in our community toolkit.
What South Dakota is doing about PFAS
As of April 2026, South Dakota has not adopted state-level PFAS drinking water standards beyond the federal EPA limits finalized in April 2024. The South Dakota Department of Agriculture and Natural Resources has tracked contamination near Ellsworth Air Force Base outside Rapid City.
Public water systems in South Dakota are subject to the federal compliance timeline requiring initial monitoring by 2027 and treatment installation by 2029.
Based on South Dakota Department of Agriculture and Natural Resources publications.
All 49 tested water systems in South Dakota
Sorted from lowest grade to highest. Click any system name for the full report. Filter by city or name with the search box below.
Showing 49 of 49 systems
| Grade | System name | City | Worst compound | vs. EPA limit | Population |
|---|---|---|---|---|---|
D | NPS-MOUNT RUSHMORE NATIONAL MEMORIAL | KEYSTONE | PFOS | 2.5× the federal limit | 4.1K |
D | RAPID VALLEY SANITARY DISTRICT | RAPID CITY | PFOS | 1.4× the federal limit | 11K |
B | RAPID CITY | RAPID CITY | PFHxS | Below federal limit | 72K |
B | ABERDEEN | ABERDEEN | PFBA | Below detection | 28K |
B | HARRISBURG, SD | HARRISBURG | PFBA | Below detection | 10K |
B | LINCOLN COUNTY RURAL WATER SYSTEM | SIOUX FALLS | PFBA | Below detection | 6.0K |
B | WR/LJ - MNI WICONI | MURDO | PFBA | Below detection | 4.7K |
A | EAGLE BUTTE | EAGLE BUTTE | - | Below detection | 4.0K |
A | BELLE FOURCHE | BELLE FOURCHE | - | Below detection | 5.6K |
A | BLACK HAWK WATER USER DISTRICT | BLACK HAWK | - | Below detection | 4.5K |
A | BOX ELDER | BOX ELDER | - | Below detection | 14K |
A | BRANDON | BRANDON | - | Below detection | 11K |
A | BROOKINGS MUNICIPAL UTILITIES | BROOKINGS | - | Below detection | 23K |
A | DELL RAPIDS | DELL RAPIDS | - | Below detection | 3.6K |
A | TRI-COUNTY RURAL WATER SYSTEM | EAGLE BUTTE | - | Below detection | 2.2K |
A | HOT SPRINGS | HOT SPRINGS | - | Below detection | 3.4K |
A | HURON | HURON | - | Below detection | 14K |
A | MADISON | MADISON | - | Below detection | 6.2K |
A | MITCHELL | MITCHELL | - | Below detection | 16K |
A | MOBRIDGE | MOBRIDGE | - | Below detection | 3.3K |
A | PHILIP | PHILIP | - | Below detection | 759 |
A | PIERRE | PIERRE | - | Below detection | 14K |
A | SIOUX FALLS | SIOUX FALLS | - | Below detection | 216K |
A | SPEARFISH | SPEARFISH | - | Below detection | 12K |
A | STURGIS | STURGIS | - | Below detection | 7.0K |
A | VERMILLION | VERMILLION | - | Below detection | 12K |
A | WATERTOWN MUNICIPAL UTILITIES | WATERTOWN | - | Below detection | 23K |
A | TEA | TEA | - | Below detection | 7.4K |
A | WALL | WALL | - | Below detection | 699 |
A | YANKTON | YANKTON | - | Below detection | 15K |
A | BIG SIOUX COMMUNITY WATER SYSTEM | EGAN | - | Below detection | 5.8K |
A | BROOKINGS-DEUEL RURAL WATER SYSTEM | TORONTO | - | Below detection | 6.2K |
A | KINGBROOK I RURAL WATER SYSTEM | ARLINGTON | - | Below detection | 6.5K |
A | MINNEHAHA COMMUNITY WATER CORP | DELL RAPIDS | - | Below detection | 13K |
A | RANDALL COMMUNITY WATER DISTRICT | LAKE ANDES | - | Below detection | 6.2K |
A | TRIPP COUNTY WATER USER DISTRICT | WINNER | - | Below detection | 4.9K |
A | CLAY RURAL WATER SYSTEM | WAKONDA | - | Below detection | 4.8K |
A | GRANT-ROBERTS RURAL WATER SYSTEM | MILBANK | - | Below detection | 5.0K |
A | BON HOMME-YANKTON RWS | TABOR | - | Below detection | 13K |
A | SIOUX RURAL WATER SYSTEM | WATERTOWN | - | Below detection | 4.0K |
A | SOUTH LINCOLN RURAL WATER SYSTEM | BERESFORD | - | Below detection | 5.3K |
A | BROWN-DAY-MARSHALL RWS | BRITTON | - | Below detection | 5.7K |
A | TM RURAL WATER DISTRICT | PARKER | - | Below detection | 4.3K |
A | WEB WATER DEVELOPMENT ASSOCIATION | ABERDEEN | - | Below detection | 21K |
A | TMT, INC. | PIERRE | - | Below detection | 250 |
A | MID-DAKOTA RURAL WATER | MILLER | - | Below detection | 12K |
A | RENDEZVOUS RANCH | BLACK HAWK | - | Below detection | 195 |
A | SUN VALLEY DEVELOPMENT | RAPID CITY | - | Below detection | 650 |
A | ELLSWORTH AFB | ELLSWORTH AFB | - | Below detection | 9.1K |
Check your water system
Enter your zip code to see the PFAS results for the water system that serves your home.
Where this data comes from
- EPA Unregulated Contaminant Monitoring Rule, 5th cycle (UCMR 5)
- Testing period: 2023 to 2026
- Federal limits: EPA Maximum Contaminant Levels finalized April 2024
- Read the full methodology