Water hardness in San Francisco
ZIP 94102

San Francisco, California water hardness report with local comparison and next-step guidance.

Hardness band
C
Quick answer

170 PPM means hard water in this ZIP code

Hard water is likely noticeable here, especially on taps, kettles, showers, and heaters.

This ZIP code is about 67 PPM softer than the California average.

At a glance
PPM
170
GPG
9.9
State average
237 PPM

Local reading

Hardness scale Hard (C)
0SoftModerateHardHigh

Water in San Francisco ZIP francisco-94102 is currently recorded at 170 PPM. That is about 9.9 grains per gallon, which is the format many softener buyers use when comparing systems.

Total Hardness
170PPM
pH Balance
7.3

Common household impact and typical response

High

Limescale on heaters and kettles

Typical response

If scaling is frequent, compare softeners or maintenance habits before replacing appliances.

Suggested next step
Compare local guides
High Risk

Dry skin and soap performance

Typical response

Hard water can make skin feel tighter and reduce lather. A full-home treatment setup is not always the first step.

Suggested next step
Review treatment basics

What this reading usually means (C)

Hard-water profile. Treatment decisions should prioritize scale control and heater efficiency.

Data quality: Eligible for indexing

Nearby ZIP codes to compare in California

Compare nearby areas to see whether this reading is unusual for the state or fairly typical nearby.

Keep comparing before you buy

A local reading is only the first step. Compare the state page and a few practical guides before deciding whether treatment is worth the money.

Source references: EPA public records, municipal water utility reports. Last technical update: 2026-04-28.