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City water profile

Castlewood water quality

Compare local ZIP estimates, evidence quality, associated public systems, and compliance history for Castlewood, South Dakota.

Median indexed hardness

1053PPM

One indexed ZIP

Range 1053–1053 PPM

State comparison
537 PPM above
State hardness rank
#36 of 222
Matched utilities
1
Active health records
0

City summary

What the indexed records say

Castlewood has 1 published ZIP profile across Hamlin County. The indexed median is 1053 PPM, compared with 516 PPM across South Dakota.

Among the 222 South Dakotacities with an indexed median, Castlewood ranks #36from highest to lowest. Across all 246 state ZIP profiles, available estimates run from 20.5to 1330 PPM.

Because only one ZIP is represented, the city median and range are the same local estimate. It should not be read as multiple independent samples across the community. At least one estimate is marked low confidence, so observation distance and date deserve extra attention.

Hardness distribution

How local ZIP estimates compare

Soft0 ZIPs
Moderately hard0 ZIPs
Hard0 ZIPs
Very hard1 ZIP

1 of 1 ZIP profiles have a hardness estimate. Bars count ZIP profiles, not households or laboratory samples.

Evidence quality

Distance, dates, and confidence

Median nearest distance
27 miles
Profiles with evidence
1/1

Confidence labels

High: 0Moderate: 0Low: 1

Observation window: May 24, 2016 to Apr 30, 2024.

ZIP directory

Water reports in Castlewood

Open a ZIP for site-level provenance and measurements.

ZIP code

57223

Very Hard

1053 PPM

Nearest site
27 mi
Confidence
Low

View full ZIP evidence →

Public water systems

Utilities associated with this city

Castlewood

PWSID SD4600002

Groundwater
System population served
698
Last reported
Jun 17, 2026

EPA SDWIS explicitly lists this ZIP in the system's served geography.

Compliance history

What EPA records show

No active health-based violation appears among the associated systems in the represented EPA reporting quarter. This does not mean every contaminant was tested at every tap.

RecordSystemPeriodStatus
Stage 1 Disinfectants and Disinfection Byproducts RuleSD4600002Jun 7, 2021Resolved · health-based

Practical next steps

Move from index to evidence

  1. 1. Open your ZIP. Check distance, dates, confidence, and the associated utility.
  2. 2. Read the current CCR. Confirm source water, detections, limits, ranges, and notices.
  3. 3. Test the tap when needed. Confirm health concerns or treatment sizing with the right method.

Questions people ask

About water in Castlewood

Is the water hard?

The indexed city median is 1053 PPM. Open the ZIP report to verify the distance and confidence behind that estimate.

Is the tap water safe?

Compliance history is utility-wide and cannot guarantee conditions at every tap. Check current notices and test when address-specific evidence is needed.

Do I need treatment?

Choose treatment only after confirming the problem at the property. A softener targets hardness; contaminant treatment requires a matching, verified performance claim.