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City water profile

Signal Hill water quality

Compare local ZIP estimates, evidence quality, associated public systems, and compliance history for Signal Hill, California.

Median indexed hardness

189PPM

One indexed ZIP

Range 189–189 PPM

State comparison
At state median
State hardness rank
#118 of 242
Matched utilities
1
Active health records
0

City summary

What the indexed records say

Signal Hill has 1 published ZIP profile across Los Angeles County. The indexed median is 189 PPM, compared with 189 PPM across California.

Among the 242 Californiacities with an indexed median, Signal Hill ranks #118from highest to lowest. Across all 678 state ZIP profiles, available estimates run from 3.3to 728.5 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.

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
17 miles
Profiles with evidence
1/1

Confidence labels

High: 0Moderate: 1Low: 0

Observation window: Jan 6, 2016 to May 14, 2026.

ZIP directory

Water reports in Signal Hill

Open a ZIP for site-level provenance and measurements.

ZIP code

90755

Very Hard

189 PPM

Nearest site
17 mi
Confidence
Moderate

View full ZIP evidence →

Public water systems

Utilities associated with this city

Signal Hill - City, Water Dept.

PWSID CA1910149

Surface water
System population served
11,848
Last reported
Jun 22, 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
Surface Water Treatment RuleCA1910149Apr 1, 2025Resolved · health-based
Surface Water Treatment RuleCA1910149Mar 1, 2025Resolved · health-based
Surface Water Treatment RuleCA1910149Feb 1, 2025Resolved · health-based
Lead and Copper RuleCA1910149Oct 1, 2023Resolved
Consumer Confidence RuleCA1910149Jul 1, 2023Resolved
Surface Water Treatment RuleCA1910149May 1, 2022Resolved · health-based
Surface Water Treatment RuleCA1910149Mar 1, 2022Resolved · 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 Signal Hill

Is the water hard?

The indexed city median is 189 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.