WaterQ
California State Report All States
Official Status: March 2026

Is San Francisco tap water safe to drink?

✓ Generally Safe
A

Mostly yes — San Francisco scores 94/100.

Safety Score
94
out of 100

Still not sure if you need a filter in San Francisco?

Read Decision Guide →

San Francisco

California

View California state report Verified: Apr 2026

Is San Francisco tap water safe to drink?

Mostly yes — San Francisco scores 94/100. This report aggregates EPA drinking water data across 1 local system in San Francisco. We found 0 total violations (0 unresolved).

Real-Time Environment

Live: 02:45 PM
0mm Precipitation

☀️ No active precipitation. Rainfall can impact surface water turbidity and pollutant runoff in San Francisco.

Water Quality Impact

✅ Minimal Impact Localized weather conditions may influence test result variability.

🛡️ Home Water Treatment Needs

Should you invest in filtration or softening for your home in San Francisco?

Requirement Status
Optional
🟢
💡

Expert Advice

Your water quality is excellent. Standard filtration is optional but can further enhance taste.

Buying a Filter?

Should you buy a water purifier in San Francisco? See our analysis.

Baby Formula Safety

Is San Francisco tap water safe for infants? Critical safety guide.

Homebuyer's Perspective

For those looking to relocate to San Francisco, water quality is a key factor in long-term property maintenance. The high safety score (94/100) suggests lower risk for plumbing corrosion and appliance scaling.

Property Impact: Positive / Stable

Health & Family Safety

Residents should monitor Selenium levels. Pregnant women and families with young children should consult the specific EPA health goals listed below.

View Health Risk Glossary →

Score Breakdown for San Francisco

EPA Compliance & Violations 85/100
Contaminant Safety Margin 94%

*Scores are calculated using weighted EPA monitoring data from the past 5 years.

Frequently Asked Questions

Is San Francisco tap water safe to drink?

Mostly yes — San Francisco scores 94/100.

How many water systems serve San Francisco?

San Francisco is served by 1 public water system in our latest EPA-backed dataset.

How can I check water quality for my exact address in San Francisco?

Use the WaterQ search tool to look up your ZIP code and view nearby systems, contaminant levels, and recent violations for San Francisco.

What is the water quality score for San Francisco?

The water quality score for San Francisco is N/A out of 100, based on EPA contaminant data, violation history, and testing results for all serving water systems.

What are the top contaminants in San Francisco?

The top contaminants detected in San Francisco include Selenium, Chlorine, Lead. View detailed information on our contaminants page.

Water Quality Score
94/100
Grade
A
Water Systems
3
Population
188,386

San Francisco Water Quality Summary

San Francisco, CA receives a water quality score of 94/100 (Grade A) based on EPA Safe Drinking Water Information System (SDWIS) compliance data for 3 public water systems serving the area.

San Francisco's water quality is above the national average, with strong compliance records and low contaminant levels. Residents generally receive clean, safe tap water that meets EPA standards.

Water quality data is sourced from the U.S. EPA SDWIS database and updated quarterly. Learn about our scoring methodology →

Key Contaminants

Selenium
42.3107 / 50 μg/L
0 μg/L MCL: 50 μg/L
Chlorine
2.1113 / 4 mg/L
0 mg/L MCL: 4 mg/L
Lead
5.9401 / 15 μg/L
0 μg/L MCL: 15 μg/L
PFAS (Per- and Polyfluoroalkyl Substances)
0.0014 / 0.004 μg/L
0 μg/L MCL: 0.004 μg/L
Haloacetic Acids (HAA5)
12.7904 / 60 μg/L
0 μg/L MCL: 60 μg/L
Chloramine
0.5133 / 4 mg/L
0 mg/L MCL: 4 mg/L
Turbidity
0.1192 / 1 NTU
0 NTU MCL: 1 NTU

Water Systems Serving San Francisco (1)

Related

Compare San Francisco water quality: View all states · Contaminant library · How we score water quality