Skip to content

City water profile

Oswego water quality

Compare local ZIP estimates, evidence quality, associated public systems, and compliance history for Oswego, Kansas.

Median indexed hardness

158PPM

One indexed ZIP

Range 158–158 PPM

State comparison
131 PPM below
State hardness rank
#421 of 484
Matched utilities
3
Active health records
0

City summary

What the indexed records say

Oswego has 1 published ZIP profile across Labette County. The indexed median is 158 PPM, compared with 289 PPM across Kansas.

Among the 484 Kansascities with an indexed median, Oswego ranks #421from highest to lowest. Across all 541 state ZIP profiles, available estimates run from 72.2to 707 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
Hard1 ZIP
Very hard0 ZIPs

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
29.9 miles
Profiles with evidence
1/1

Confidence labels

High: 0Moderate: 0Low: 1

Observation window: Jan 26, 2016 to Apr 20, 2026.

ZIP directory

Water reports in Oswego

Open a ZIP for site-level provenance and measurements.

ZIP code

67356

Hard

158 PPM

Nearest site
29.9 mi
Confidence
Low

View full ZIP evidence →

Public water systems

Utilities associated with this city

Oswego, City Of

PWSID KS2009908

Surface water
System population served
1,680
Last reported
May 15, 2026

The system names this served city; Census place overlap links the city to this ZCTA.

Labette Co Rwd 5

PWSID KS2009906

Surface water
System population served
1,635
Last reported
May 15, 2026

The system names this served city; Census place overlap links the city to this ZCTA.

Labette Co Rwd 1c

PWSID KS2009919

Surface water
System population served
285
Last reported
May 15, 2026

The system names this served city; Census place overlap links the city to this ZCTA.

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
LEAD AND COPPER RULE REVISIONSKS2009906Jul 2, 2025Unaddressed
Lead and Copper RuleKS2009919Jan 1, 2025Resolved
LEAD AND COPPER RULE REVISIONSKS2009919Oct 17, 2024Unaddressed
Surface Water Treatment RuleKS2009908Aug 1, 2024Resolved
Surface Water Treatment RuleKS2009908Jan 1, 2024Resolved
Surface Water Treatment RuleKS2009908Jun 1, 2023Resolved
ChloriteKS2009908Jul 1, 2021Resolved · health-based
Public NoticeKS2009919Jun 18, 2021Resolved
Revised Total Coliform RuleKS2009919Apr 27, 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 Oswego

Is the water hard?

The indexed city median is 158 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.