Redwood City
CA

Is Redwood City, CA Tap Water Safe to Drink?

Redwood City, CA tap water currently meets EPA health guidelines across all monitored ZIP codes in this dataset. Contaminants including lithium have been detected at or below guideline thresholds.

3Water systems
3ZIP codes
0%ZIPs above EPA guideline
Metro areaSan Francisco-Oakland-Fremont, CA
Latest data2025-06-06

Where Does Redwood City Get Its Water?

Water in Redwood City, CA is provided by 3 public water systems: CITY OF REDWOOD CITY, CALIFORNIA WATER SERVICE - BEAR GULCH and CALIFORNIA WATER SERVICE - SAN CARLOS.

How Is Redwood City Tap Water Treated?

Treated water is disinfected using calcium hypochlorite. Treatment includes conventional treatment (coagulation, flocculation, and filtration) and direct filtration.

What's in Redwood City Tap Water?

The following contaminants were detected most frequently in Redwood City public water systems. All detected levels fall at or below EPA health guidelines in this dataset.

ContaminantPeak detectedEPA guidelineZIPs detectedStatus
lithium 9 µg/L — 0 ZIPs Within guideline
PFTrDA 0.007 µg/L 0.007 µg/L 2 ZIPs Within guideline
11Cl-PF3OUdS 0.005 µg/L — 0 ZIPs Within guideline
8:2 FTS 0.005 µg/L — 0 ZIPs Within guideline
6:2 FTS 0.005 µg/L — 0 ZIPs Within guideline

Health Risk Profile for Redwood City

Current EPA monitoring data for Redwood City shows contaminant levels within guideline thresholds across all ZIP codes in this dataset. As with all public water systems, sensitive populations may choose to use a certified filter for additional peace of mind.

Best Filters for PFAS Water Profile

PFAS compounds are detected in this water supply. A reverse osmosis (RO) system or an activated-carbon filter specifically certified under NSF/ANSI P473 is required for reliable PFAS reduction. Standard pitcher and faucet filters without P473 certification do not remove PFAS.

Waterdrop G3P600 Reverse Osmosis System
Under-sink RO system

8-stage tankless RO system certified to NSF/ANSI 58, reduces 1,000+ contaminants including PFAS, lead, arsenic, fluoride, and nitrates.

Epic Pure XP Water Filter Pitcher
Pitcher filter

NSF-certified dual-layer filtration reduces 70+ contaminants including PFAS, lead, chlorine, microplastics, and bacteria.

See recommendations matched to your exact address: choose your ZIP code below.

Frequently Asked Questions about Redwood City Tap Water

Is Redwood City tap water safe to drink?

Redwood City tap water currently meets EPA health guidelines across all monitored ZIP codes in this dataset. Sensitive populations may still choose to use a certified filter as a precaution.

What contaminants are in Redwood City tap water?

The most commonly detected contaminants in Redwood City water systems include: lithium, PFTrDA, 11Cl-PF3OUdS. See the ZIP-level reports for exact measurements and EPA guideline comparisons.

Where does Redwood City get its drinking water?

Redwood City receives water from 3 public water systems, including CITY OF REDWOOD CITY.

Do I need a water filter in Redwood City?

Current data does not show guideline exceedances in Redwood City. A certified filter can still reduce trace contaminants and improve taste for households that prefer filtered water.

How often is Redwood City tap water tested?

Public water systems in Redwood City are required by the EPA to test for regulated contaminants on schedules ranging from daily (for microbials and disinfectants) to annual or triennial (for many chemical contaminants). Results are published in annual Consumer Confidence Reports (CCRs). The data on this page reflects the most recent available EPA monitoring results, with the latest sample date of 2025-06-06.

Tap water reports by ZIP in Redwood City

Water utilities serving Redwood City, CA

Service area boundaries are approximate and based on state filings or modeled estimates. Contact your utility to confirm exact service at a specific address.

Modeled boundaries are shown with a dashed outline.

Also covers / overlaps with