ZIP Code 94555 Water Quality & Testing Report
Fremont, CA · Alameda County County · Updated for 2026
Is Tap Water Safe to Drink in ZIP 94555 (Fremont, CA)?
Yes, tap water in ZIP code 94555 (Fremont, CA) is safe to drink under EPA Safe Drinking Water Act standards. Supplied by Alameda County Water District, the area earns an EPA Safety Grade of B (78/100) with 1 health violations, 5.3 ppb lead, and hard (133 mg/L / 7.8 GPG) water.
Water Safety Grade
Good — Minor issues on record
Health Violations
1
Total Violations
8
Lead Risk
High
Contaminants
1
Active Water Quality Issues Detected
EPA records show 3 unresolved violations. Contact Alameda County Water District for current status.
About Tap Water in ZIP Code 94555
Tap water in ZIP code 94555 (Fremont, CA) is distributed by Alameda County Water District (EPA ID: CA0110001), serving approximately 344,000 residents. Based on EPA Safe Drinking Water Act compliance records, this system receives a water safety grade of B with a composite quality score of 78/100.
Water System
Alameda County Water District
EPA ID: CA0110001
Water Source
Surface Water
Population Served
344,000 residents
County
Alameda County County, California
Lead Levels in ZIP 94555
EPA action level: 15 ppb | Public health goal: 0 ppb
Lead Level: 5.3 ppb — Moderate
Lead exposure risk in 94555 is rated High. EPA models estimate a 54% exposure probability based on housing and infrastructure age.
From annual CCR filing
From annual CCR filing
EPA model estimate based on housing age and infrastructure
Water Hardness & Mineral Content
Grains per gallon (GPG) & Parts per million (PPM / mg/L)
Water in ZIP 94555 is Hard (133 mg/L / 7.8 GPG). Residents may notice white mineral spots on glassware, reduced soap efficiency, and mineral scale on faucets and showerheads.
Grains per gallon
Parts per million CaCO3
Official EPA SDWIS Database Entry
Utility: Alameda County Water District · PWSID: CA0110001
Violation History
Past 5 years — EPA SDWIS data
Alameda County Water District has recorded 1 health-based violation out of 8 total violations over the past 5 years. 3 violations remain unresolved in EPA tracking records.
Regulatory compliance risk for this utility is rated High based on past reporting and enforcement records.
Contaminants Detected
Contaminants with health-based violations on record
EPA records identify 1 contaminant with health-based violations in the past 5 years: Stage 2 DBP Rule.
From Consumer Confidence Report:
Aluminum (0.07 ppm); Bromate (6.1 ppb); Disinfectant Residual (as Cl2) (3.4 ppm); 5 Haloacetic Acids (HAA5) (46 ppb); Total Trihalomethanes (TTHMs) (62 ppb)
⚖ Enforcement Actions
Water Source & Environmental Factors
Surface Water
This system draws water from lakes, rivers, or reservoirs. Surface water is treated to remove sediment, microorganisms, and chemical contaminants before reaching taps.
Moderate potential
% of household income spent on energy — indicator of older infrastructure
EPA Radon Zone 2 — moderate radon potential. The EPA recommends testing your home regardless of zone designation.
Water Quality Testing in ZIP 94555
Tap Water & Well Testing Recommendations
Residents in ZIP code 94555 served by Alameda County Water District can test tap water or private well systems to verify water purity. Testing detects hidden contaminants before they impact family health.
Tap Water Testing Steps
- 1.Conduct a certified lead check if your home was constructed before 1986.
- 2.Use certified lab testing kits rather than uncalibrated test strips for regulated compliance.
- 3.Sample water from both your kitchen faucet and water heater to compare line purity.
Private Well Testing Steps
- •Test for Coliform bacteria and Nitrates annually.
- •Test for heavy metals, radon, and PFAS every 3 years.
- •Send samples to a state-certified drinking water laboratory recognized by California State Water Resources Control Board.
🛡 What Should You Do? — ZIP 94555 Recommendations
Your water quality is good
- ✓ Run cold water for 30 seconds each morning before use — especially if pipes are old
- ✓ Request your annual Consumer Confidence Report from Alameda County Water District
- ✓ If your home was built before 1986, consider testing your own tap for lead
- ✓ Use a pitcher filter (NSF/ANSI 42 certified) for improved taste
Recommended Taste & Safety Filter:
NSF/ANSI 53 Certified Pitcher Filter
Best for removing aesthetic chlorine, odors, and low-level heavy metals.
Frequently Asked Questions — ZIP 94555 Water Quality
Is tap water safe to drink in ZIP code 94555?+
How do I get my water tested in ZIP 94555 (Fremont, CA)?+
How hard is the tap water in 94555?+
Should I test private well water in 94555?+
What is the lead level in 94555 tap water?+
Is there an active boil water notice in 94555?+
Who provides tap water to 94555?+
What water filter should I use in 94555?+
Data Sources & Methodology
Water quality data for ZIP code 94555 is compiled from the EPA Safe Drinking Water Information System (SDWIS), EPA ECHO enforcement database, UCMR5 unregulated contaminant monitoring, and Consumer Confidence Reports filed by Alameda County Water District. Safety scores are composite metrics derived from violation history, lead levels, enforcement actions, and infrastructure risk indicators. Data reflects a 5-year monitoring window. Last dataset update: 2024. View EPA source data →