How does Yankton's water compare to the national average?

The USA national average is 151 mg/L. Yankton (870 mg/L) is 719 mg/L harder than average.

Yankton Water Hardness & Quality Report (2026)

Water Hardness

870mg/L

Very Hard

50.8 grains per gallon

Source

groundwater

pH Level

8.2

neutral = 7.0

Lead

0.004 mg/L

✓ Below action level

TDS

3000 mg/L

Est. Daily Cost

$1.00

energy & soap waste

Source: See methodology section below · Updated 2026

870mg/L as CaCO₃Very Hard

0–60

mg/L

Soft

61–120

mg/L

Moderately Hard

121–180

mg/L

Hard

180+

mg/L

Very Hard

Appliance Damage Report

In Yankton, your appliances are currently losing 45% efficiency due to mineral buildup.

Appliance	In Yankton	Soft Water City	Efficiency Loss
Kettle	1.5 yrs	8.5 yrs	-82%
Washing Machine	3 yrs	12 yrs	-75%
Water Heater	5 yrs	15 yrs	-67%

Regional Water Comparison

How Yankton compares to its nearest neighbours

City	Hardness	Risk	Source
▶ Yankton, South Dakota	870 mg/L	🔴 Very Hard	groundwater
Vermillion, South Dakota	≈ 180+ mg/L	🔴 Very Hard	groundwater
Norfolk, Nebraska	≈ 120–179 mg/L	🟠 Hard	groundwater
Sioux Falls, South Dakota	≈ 120–179 mg/L	🟠 Hard	reservoir
Mitchell, South Dakota	581.08 mg/L	🔴 Very Hard	reservoir

National Benchmark

How Yankton compares to the USA average

Benchmark	Hardness	Appliance Risk
▶ Yankton	870 mg/L	🔴 High
USA National Avg	151 mg/L	🟠 Moderate
Scarsdale Top Rated	0.02 mg/L	🟢 None

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What Makes Yankton's Water Unique?

Local geology and source profile

Source: GroundwaterTDS: 3000 mg/LpH: 8.2

The City of Yankton Water Utility supplies residents of Yankton, South Dakota, drawing its water from beneath the Missouri River valley. This groundwater is treated at Water Plant #2. For detailed water quality information, Kyle Goodmanson, Director of Environmental Services, can be reached at (605) 668-5272. The utility also makes its annual Drinking Water Report available on the City of Yankton's official website, offering a comprehensive look at the water's quality and treatment.

The water's origin lies in ancient sedimentary deposits and calcium-rich bedrock, specifically Cretaceous and older geological formations. This region's geology, characterized by the Missouri River valley aquifer system, is rich in minerals like calcium and sodium sulfate. These dissolved minerals, originating from limestone, dolomite, and other carbonate-bearing strata, are the reason for the groundwater's very hard, highly mineralized profile, a common trait for this part of southeastern South Dakota.

This very hard water can lead to significant scale buildup in appliances like water heaters, kettles, dishwashers, and washing machines, potentially shortening their lifespan. You'll likely find that soaps and detergents don't lather as effectively, requiring more product for cleaning. Many homeowners opt for whole-house or point-of-use water softening systems to combat these issues and protect their plumbing. Regular descaling of water-using appliances is a good maintenance practice. Yankton's water shows a specific conductance averaging 1,910 micromhos, consistent with the region's groundwater.

Geology & Source: Cretaceous and older sedimentary deposits; calcium-rich bedrock and calcium-sodium-sulfate minerals produce very hard water.

Other South Dakota Water Reports

Vermillion

≈ 180+ mg/L

🔴 Very Hard

Norfolk

≈ 120–179 mg/L

🟠 Hard

Sioux Falls

≈ 120–179 mg/L

🟠 Hard

Mitchell

581.08 mg/L

🔴 Very Hard

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Notice an error or missing data? Help us keep this page accurate. If you spot incorrect water hardness, outdated utility info, or missing details, please let us know.

All reports are reviewed by our team. Thank you for supporting data quality!

Frequently Asked Questions

Is Yankton's water safe to drink?

Yes. Yankton's water meets all federal safety standards. The hardness is 870 mg/L (Very Hard), which is safe to drink. High hardness affects appliances and taste, but poses no health risk.

Do I need a water softener in Yankton?

At 870 mg/L (Very Hard), Yankton's water will cause significant limescale on kettles, washing machines, and water heaters. A water softener or descaler is strongly recommended to extend appliance lifespan and reduce energy bills by up to 45%.

How does Yankton compare to the USA average?

The USA national average is 151 mg/L. Yankton (870 mg/L) is 719 mg/L above the national average. The softest major city is Scarsdale at just 0.02 mg/L.

Data Sources & Methodology

Water quality data for Yankton is derived from geographic and geological modelling of the surrounding region. No federal monitoring station data was available for this location.

Estimated

Water Hardness

Modelled estimate based on state-level USGS geological survey data for this region. No direct USGS Water Quality Portal measurement was matched to this city — the value reflects a statistical range calibrated to the state's dominant rock types and typical source water characteristics.

Estimated

Estimated from regional geology and source water characteristics. pH is correlated with water hardness and local bedrock — values may differ from utility-reported figures.

Estimated

TDS — Total Dissolved Solids

Estimated using a derived ratio from water hardness and regional conductance profiles. TDS in natural water correlates strongly with total mineral content including hardness ions.

Measured

PFAS — Perfluoroalkyl and Polyfluoroalkyl Substances

EPA UCMR5 (5th Unregulated Contaminant Monitoring Rule, 2023–2025) — sum of PFAS compounds detected at the public water system serving this city. A value of 0 indicates the system was sampled with no detection above reporting limits.

Modelled

Lead

Modelled estimate based on the EPA Lead and Copper Rule 90th-percentile tap-sample methodology. No publicly available per-city lead dataset with sufficient national coverage exists. Values are a conservative baseline derived from city population tier and infrastructure age — all estimates are maintained below the EPA action level of 0.015 mg/L.

Calculated

Appliance Lifespan

Calculated from water hardness using a linear degradation model. Baseline lifespans represent soft-water performance (kettle: 8.5 yrs, washing machine: 12.0 yrs, water heater: 15.0 yrs). Hard water mineral scale progressively reduces operational life in direct proportion to hardness concentration.