Is South Dakota Tap Water Safe to Drink?
Water quality data for 7 cities across South Dakota. Find your city below.
Water quality in South Dakota varies significantly from city to city. Across 7 cities we track, hardness ranges from 204 PPM in Aberdeen to 280 PPM in Mitchell, with a statewide average of 244 PPM. 7 of 7 cities have hard water above 120 PPM where a water softener provides measurable benefits.
7
Cities
244
Avg Hardness (PPM)
280
Hardest City (PPM)
Complete South Dakota Guide
Statewide water quality overview, costs, and treatment recommendations.
Well Water in South Dakota
Testing, treatment, and common issues for private wells.
Hardest Water Rankings
South Dakota cities ranked by water hardness level.
City Comparisons
Mitchell vs Aberdeen
Side-by-side water quality comparison.
Mitchell vs Watertown
Side-by-side water quality comparison.
Watertown vs Sioux Falls
Side-by-side water quality comparison.
South Dakota Cities by Water Hardness
| City | Hardness (PPM) | Level | PFAS (ppt) | Source |
|---|---|---|---|---|
| Mitchell | 280 | Extremely Hard | 0 | Firesteel Creek & wells |
| Watertown | 260 | Extremely Hard | 0 | Lake Kampeska & wells |
| Sioux Falls | 250 | Extremely Hard | 0 | Big Sioux River + wells |
| Sioux Falls Downtown | 250 | Extremely Hard | 0 | Big Sioux River + wells |
| Brookings | 240 | Very Hard | 0 | Big Sioux Aquifer wells |
| Rapid City | 221 | Very Hard | 4.85 | Pactola Reservoir, groundwater |
| Aberdeen | 204 | Very Hard | 7.37 | Elm River aquifer |
Frequently Asked Questions About South Dakota Water
Is South Dakota tap water safe to drink?
South Dakota tap water meets EPA legal standards in most cities. The statewide average hardness of 244 PPM means most homes deal with hard water effects like scale buildup, though hardness is not a health concern. Check your specific city above for detailed data.
Do I need a water softener in South Dakota?
Most South Dakota cities would benefit from a water softener. The state average is 244 PPM, and 100% of cities exceed 120 PPM where softener benefits become measurable. A salt-based softener reduces scale damage, energy waste, and product use.
Which South Dakota city has the hardest water?
Mitchell has the hardest water in South Dakota at 280 PPM (16.4 GPG). Watertown is second at 260 PPM. See the full ranking.
What contaminants are in South Dakota water?
The most common concerns across South Dakota are hard water minerals (calcium and magnesium). Each city has different levels - check your city above for specific contaminant data.
How much does a water softener cost in South Dakota?
A whole-house water softener for a typical South Dakota home costs $800-$2,500 installed, depending on capacity and brand. At 244 PPM average hardness, most homes need a 32,000-48,000 grain system. Full cost breakdown.