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South Dakota Tap Water Quality 2026

EPA drinking water data for 459 cities across South Dakota — covering lead levels, violation history, and compliance status.

Systems tracked: 272 Cities covered: 459 Updated: 2026 Q2
A

South Dakota earns an A for overall water quality

459 communities across 66 counties and 272 water systems. 96.3% have no open violations.

Median lead where detected: 2.00 ppb
8.5% of systems report lead as not detected — a state filing convention, not a water quality measure
PFAS tested at 37.7% of communities; 0 above the federal limit
Lead reported for 100.0% of communities
96.3% of communities have no open violations
Water Systems
272
Active community systems
Median Lead Level
2 ppb
13% of EPA action level
Fully Compliant
96.3%
of systems — no active violations
How we grade states Grades are based on actual EPA enforcement data — MCL violations and lead levels measured against the 15 ppb federal action level. We do not use MCLG-based detections, which are aspirational zero-tolerance goals that would make nearly every state look dangerous. Read our full methodology →

Best & Worst Cities in South Dakota

✓ Cleanest Water
Sioux Falls
Minnehaha County
3.0 ppb A
Mitchell
Davison County
1.0 ppb A
Vermillion
Clay County
1.0 ppb A
Spearfish
Lawrence County
3.0 ppb A
Sturgis
Meade County
2.0 ppb A
Rapid Valley
Pennington County
3.0 ppb A
⚠ Needs Attention
Rosebud
Todd County
0.4 ppb D
Antelope
Todd County
0.4 ppb D
Parmelee
Todd County
0.4 ppb D
Two Strike
Todd County
0.4 ppb D
Mountain Plains
Lawrence County
1.0 ppb D
Spring Creek
Todd County
0.4 ppb D

Water Quality by County

66 of 66
Sort:
CountySystemsLead LevelViolationsGrade
Minnehaha County 17 1.0 ppb 0 A
Brown County 16 2.0 ppb 0 A
Spink County 15 2.0 ppb 0 A
Beadle County 13 2.0 ppb 0 A
Pennington County 13 2.0 ppb 0 A
Hutchinson County 12 1.0 ppb 0 A
Clark County 12 2.0 ppb 0 A
Lake County 11 2.0 ppb 0 A
Todd County 11 0.4 ppb 0 C
Roberts County 11 2.0 ppb 0 B

About South Dakota Drinking Water

South Dakota is served by 272 community water systems covering 459 communities across 66 counties. 96.3% have no open violation on record.

Lead was detected in 420 communities, with a median of 2.00 ppb — 13% of the federal action level. A further 39 reported none detected. That share is a state reporting convention rather than a measure of water quality, so it is stated separately rather than averaged in.

PFAS has been tested at 37.7% of communities here, and 0 are above the limits EPA set in 2024. Coverage matters: states that test more find more, so this figure is not comparable with a state that has tested less.

Frequently Asked Questions

Is South Dakota tap water safe to drink? ▼
96.3% of communities have no open violation on record. No community has PFAS above the federal limit on record.
Does South Dakota have a lead problem? ▼
1 water systems report a 90th-percentile lead result at or above the 15 ppb action level. The action level is a treatment trigger, not a legal maximum, and 39 communities report no detection at all.
How complete is the data for South Dakota? ▼
Lead results are reported for 100.0% of communities and PFAS for 37.7%. Where a figure is missing it is shown as not reported rather than assumed safe.
How does South Dakota compare with other states? ▼
We do not rank states against each other. Lead reporting completeness ranges from under 20% to 100% depending on the state, so a national ranking would compare filing practice rather than water quality.