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City water profile

Louisville water quality

Compare local ZIP estimates, evidence quality, associated public systems, and compliance history for Louisville, Kentucky.

Median indexed hardness

132PPM

17 indexed ZIPs

Range 132–132 PPM

State comparison
25 PPM below
State hardness rank
#102 of 129
Matched utilities
1
Active health records
0

City summary

What the indexed records say

Louisville has 17 published ZIP profiles across Jefferson County. The indexed median is 132 PPM, compared with 157 PPM across Kentucky.

Among the 129 Kentuckycities with an indexed median, Louisville ranks #102from highest to lowest. Across all 164 state ZIP profiles, available estimates run from 32.6to 360 PPM.

The 132–132 PPM range shows how much the available ZIP estimates vary within the city label. 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
Hard17 ZIPs
Very hard0 ZIPs

17 of 17 ZIP profiles have a hardness estimate. Bars count ZIP profiles, not households or laboratory samples.

Evidence quality

Distance, dates, and confidence

Median nearest distance
57 miles
Profiles with evidence
17/17

Confidence labels

High: 0Moderate: 0Low: 17

Observation window: Jan 21, 2016 to May 27, 2026.

ZIP directory

Water reports in Louisville

Open a ZIP for site-level provenance and measurements.

ZIP code

40041

Hard

132 PPM

Nearest site
61.7 mi
Confidence
Low

View full ZIP evidence →

ZIP code

40202

Hard

132 PPM

Nearest site
57.3 mi
Confidence
Low

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ZIP code

40203

Hard

132 PPM

Nearest site
56.7 mi
Confidence
Low

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ZIP code

40204

Hard

132 PPM

Nearest site
58.4 mi
Confidence
Low

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ZIP code

40205

Hard

132 PPM

Nearest site
59.9 mi
Confidence
Low

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ZIP code

40206

Hard

132 PPM

Nearest site
59.9 mi
Confidence
Low

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ZIP code

40208

Hard

132 PPM

Nearest site
55.6 mi
Confidence
Low

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ZIP code

40209

Hard

132 PPM

Nearest site
56.3 mi
Confidence
Low

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ZIP code

40210

Hard

132 PPM

Nearest site
55 mi
Confidence
Low

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ZIP code

40211

Hard

132 PPM

Nearest site
53.3 mi
Confidence
Low

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ZIP code

40212

Hard

132 PPM

Nearest site
55.3 mi
Confidence
Low

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ZIP code

40213

Hard

132 PPM

Nearest site
57.1 mi
Confidence
Low

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ZIP code

40215

Hard

132 PPM

Nearest site
53.9 mi
Confidence
Low

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ZIP code

40217

Hard

132 PPM

Nearest site
57 mi
Confidence
Low

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ZIP code

40221

Hard

132 PPM

Nearest site
55.5 mi
Confidence
Low

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ZIP code

40231

Hard

132 PPM

Nearest site
58.7 mi
Confidence
Low

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ZIP code

40280

Hard

132 PPM

Nearest site
60.4 mi
Confidence
Low

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Public water systems

Utilities associated with this city

Louisville Water Company

PWSID KY0560258

Surface water
System population served
806,997
Last reported
Jun 18, 2026

A municipal system, in-state city, and served county all agree with this Census 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.

No violation records are included in the current lookback window.

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 Louisville

Is the water hard?

The indexed city median is 132 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.