Skip to content

City water profile

Watertown water quality

Compare local ZIP estimates, evidence quality, associated public systems, and compliance history for Watertown, Wisconsin.

Median indexed hardness

395PPM

2 indexed ZIPs

Range 394–395 PPM

State comparison
107 PPM above
State hardness rank
#56 of 479
Matched utilities
3
Active health records
0

City summary

What the indexed records say

Watertown has 2 published ZIP profiles across Jefferson County and Dodge County. The indexed median is 395 PPM, compared with 288 PPM across Wisconsin.

Among the 479 Wisconsincities with an indexed median, Watertown ranks #56from highest to lowest. Across all 556 state ZIP profiles, available estimates run from 41.3to 467 PPM.

The 394–395 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
Hard0 ZIPs
Very hard2 ZIPs

2 of 2 ZIP profiles have a hardness estimate. Bars count ZIP profiles, not households or laboratory samples.

Evidence quality

Distance, dates, and confidence

Median nearest distance
26.1 miles
Profiles with evidence
2/2

Confidence labels

High: 0Moderate: 1Low: 1

Observation window: Aug 3, 2016 to Aug 20, 2024.

ZIP directory

Water reports in Watertown

Open a ZIP for site-level provenance and measurements.

ZIP code

53094

Very Hard

394 PPM

Nearest site
23.9 mi
Confidence
Moderate

View full ZIP evidence →

ZIP code

53098

Very Hard

395 PPM

Nearest site
26.1 mi
Confidence
Low

View full ZIP evidence →

Public water systems

Utilities associated with this city

Watertown Waterworks

PWSID WI1280044

Groundwater
System population served
23,945
Last reported
May 29, 2026

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

Hidden Meadows

PWSID WI1140016

Groundwater
System population served
166
Last reported
May 29, 2026

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

Hickory Hill Park Llc

PWSID WI1280116

Groundwater
System population served
31
Last reported
May 29, 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
Combined Radium (-226 and -228)WI1140016Jan 1, 2026Archived · health-based
Combined Radium (-226 and -228)WI1140016Oct 1, 2025Archived · health-based
Public NoticeWI1140016Jul 21, 2025Resolved
StyreneWI1140016Jul 1, 2025Resolved
EthylbenzeneWI1140016Jul 1, 2025Resolved
BenzeneWI1140016Jul 1, 2025Resolved
DICHLOROMETHANEWI1140016Jul 1, 2025Resolved
o-DichlorobenzeneWI1140016Jul 1, 2025Resolved
trans-1,2-DichloroethyleneWI1140016Jul 1, 2025Resolved
1,2-DichloropropaneWI1140016Jul 1, 2025Resolved

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 Watertown

Is the water hard?

The indexed city median is 395 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.