Vermillion Water Hardness & Quality Report (2026)
Water Hardness
180+ mg/L
Very Hardestimated · not lab-verified
Source
groundwater
pH Level
7.8
neutral = 7.0
Lead
0.002 mg/L
✓ Below action level
TDS
343.6 mg/L
Est. Daily Cost
$0.91
energy & soap waste
Source: See methodology section below · Updated 2026
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 Vermillion, your appliances are currently losing 45% efficiency due to mineral buildup.
| Appliance | In Vermillion | Soft Water City | Efficiency Loss |
|---|---|---|---|
| Kettle | 4.7 yrs | 8.5 yrs | -45% |
| Washing Machine | 6.6 yrs | 12 yrs | -45% |
| Water Heater | 8.3 yrs | 15 yrs | -45% |
Regional Water Comparison
How Vermillion compares to its nearest neighbours
| City | Hardness | PFAS (ppt) | Risk | Source |
|---|---|---|---|---|
| ▶ Vermillion, South Dakota | ≈ 180+ mg/L | 0 ppt | 🔴 Very Hard | groundwater |
| Yankton, South Dakota | 870 mg/L | 0 ppt | 🔴 Very Hard | groundwater |
| Sioux City, Iowa | ≈ 180+ mg/L | 464.9 ppt | 🔴 Very Hard | mixed |
| South Sioux City, Nebraska | ≈ 120–179 mg/L | 0 ppt | 🟠 Hard | mixed |
| Sioux Falls, South Dakota | ≈ 120–179 mg/L | 0 ppt | 🟠 Hard | reservoir |
National Benchmark
How Vermillion compares to the USA average
| Benchmark | Hardness | Appliance Risk |
|---|---|---|
| ▶ Vermillion | ≈ 180+ mg/L | 🔴 High |
| USA National Avg | 151 mg/L | 🟠 Moderate |
| Scarsdale Top Rated | 0.02 mg/L | 🟢 None |
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What Makes Vermillion's Water Unique?
Local geology and source profile
The City of Vermillion Public Water System supplies drinking water to about 11,000 residents in Clay County, South Dakota. This utility draws exclusively from the Lower Missouri River Out-Wash Aquifer, accessing groundwater through wells drilled to approximately 100 feet. The water then travels to the Vermillion Water Treatment Plant. There, it undergoes a multi-stage process: aeration to remove dissolved gases, softening to reduce mineral content, filtration, chlorination, and fluoridation before being sent to homes and businesses. The aquifer itself is replenished by rainfall and infiltration from the Lower Missouri River valley in southeastern South Dakota.
The aquifer's geological foundation is composed of Pleistocene glacial outwash, featuring sands and gravels laid down by the Missouri River. These unconsolidated sediments rest above Cretaceous bedrock, specifically the Pierre Shale and Niobrara Formation. The outwash material is rich in limestone and other calcareous substances, derived from glacial till. As water percolates through these formations, it dissolves these minerals, leading to a naturally hard water supply due to the calcareous nature of the local geology and the aquifer's matrix.
This naturally hard water can lead to significant scale buildup, primarily impacting appliances like water heaters, dishwashers, and washing machines, as well as fixtures such as faucets and showerheads. This buildup reduces their efficiency and shortens their lifespan. Additionally, boilers and pipes can become clogged, potentially increasing energy costs. Homeowners can mitigate these effects by deliming appliances annually, installing scale-inhibiting filters, and flushing hot water systems periodically. A whole-house water softener is strongly recommended to combat the hard water's impact. The City of Vermillion Public Water System conducts daily tests for hardness, chlorine, and fluoride, along with monthly bacteria checks and quarterly inorganic analyses, ensuring compliance with EPA standards.
Geology & Source: Lower Missouri River Out-Wash Aquifer; Pleistocene glacial deposits rich in limestone and dolomite impart significant hardness
Other South Dakota Water Reports
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Frequently Asked Questions
Is Vermillion's water safe to drink?
Do I need a water softener in Vermillion?
How does Vermillion compare to the USA average?
Data Sources & Methodology
Water quality data for Vermillion is derived from geographic and geological modelling of the surrounding region. No federal monitoring station data was available for this location.
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.
pH
Estimated from regional geology and source water characteristics. pH is correlated with water hardness and local bedrock — values may differ from utility-reported figures.
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.
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.
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.
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.