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

The USA national average is 151 mg/L. Brookings (≈ 180+ mg/L) is 189 mg/L harder than average.

Brookings Water Hardness & Quality Report (2026)

Water Hardness

very hard

180+ mg/L

Very Hard

estimated · not lab-verified

Source

groundwater

pH Level

8.5

neutral = 7.0

Lead

0.007 mg/L

✓ Below action level

TDS

1114.3 mg/L

Est. Daily Cost

$0.91

energy & soap waste

Source: See methodology section below · Updated 2026

very hard180+ mg/LVery Hard · est.

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

Appliance	In Brookings	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 Brookings compares to its nearest neighbours

City	Hardness	PFAS (ppt)	Risk	Source
▶ Brookings, South Dakota	≈ 180+ mg/L	0 ppt	🔴 Very Hard	groundwater
Watertown, South Dakota	≈ 120–179 mg/L	0 ppt	🟠 Hard	groundwater
Sioux Falls, South Dakota	≈ 120–179 mg/L	0 ppt	🟠 Hard	reservoir
Marshall, Minnesota	≈ 120–179 mg/L	8.4 ppt	🟠 Hard	groundwater
Mitchell, South Dakota	581.08 mg/L	0 ppt	🔴 Very Hard	reservoir

National Benchmark

How Brookings compares to the USA average

Benchmark	Hardness	Appliance Risk
▶ Brookings	≈ 180+ mg/L	🔴 High
USA National Avg	151 mg/L	🟠 Moderate
Scarsdale Top Rated	0.02 mg/L	🟢 None

Bring Scarsdale-quality water to your Brookings home

Shop water softeners on Amazon.com →

Shop Now

What Makes Brookings's Water Unique?

Local geology and source profile

Source: GroundwaterTDS: 1114.3 mg/LpH: 8.5

Brookings Municipal Utilities (BMU) serves the city of Brookings in Brookings County, South Dakota, operating a groundwater-based public water supply system. The utility draws from the Big Sioux Aquifer and related Cretaceous/Paleozoic aquifer formations, with treatment facilities located at 525 Western Avenue, Brookings, SD 57006. A separate entity, Brookings-Deuel Rural Water System (EPA ID: 0430), also serves residential areas in Brookings and Deuel counties as a private groundwater utility.

The water supply originates from deep aquifer systems underlying the northern Great Plains, where ancient limestone and dolomite formations of Paleozoic age dissolve slowly into groundwater. The Big Sioux Aquifer and associated formations are the primary source. This geological setting — characterized by extensive carbonate rock layers — naturally produces very hard water typical of South Dakota's landscape, with the municipal supply relying on groundwater rather than surface sources.

Very hard water causes rapid scale buildup in kettles, coffee makers, dishwashers, and water heaters, reducing efficiency and lifespan. Soap and detergent effectiveness is reduced, requiring higher doses; hard water staining appears on glassware and fixtures. A water softener is strongly recommended to reduce scale formation and extend appliance life. The 2022 Water Quality Report from Brookings Municipal Utilities documents compliance with Safe Drinking Water Act standards; the utility tests regularly for nitrates, fluoride, and other regulated parameters.

Geology & Source: Big Sioux Aquifer — Cretaceous and Paleozoic limestone and dolomite beneath the northern Great Plains; carbonate dissolution produces very hard water characteristic of South Dakota

Other South Dakota Water Reports

Watertown

≈ 120–179 mg/L

🟠 Hard

Sioux Falls

≈ 120–179 mg/L

🟠 Hard

Marshall

≈ 120–179 mg/L

🟠 Hard

Mitchell

581.08 mg/L

🔴 Very Hard

Report an Issue

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 Brookings's water safe to drink?

Yes. Brookings's water meets all federal safety standards. The hardness is ≈ 180+ 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 Brookings?

At ≈ 180+ mg/L (Very Hard), Brookings'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 Brookings compare to the USA average?

The USA national average is 151 mg/L. Brookings (≈ 180+ mg/L) is 189 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 Brookings 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.