Is Daly City, CA Tap Water Safe to Drink?
Yes, Daly City tap water is safe to drink. Hardness is low at 34 PPM, and no contaminants exceed health guidelines. Most homes here don't need treatment.
Hardness Scale: Where Daly City Falls
0Slightly
60Moderate
120Hard
180Very Hard
250Extreme
400+
How Daly City Compares
Daly City's water is 75% softer than the national average of 138 PPM - ranking in the bottom 80% for hardness nationwide. Most homes here do not need a softener. Within California, it ranks #84 of 87 cities (81% below the state average of 180 PPM). Among mid-size cities (100k-200k), Daly City ranks #154 of 189 for hardness.
What Daly City's Water Means for Your Home
Hardness: 34 PPM - Low Concern
Daly City's water is slightly hard at 34 PPM. Most households won't notice any issues at this level. Scale buildup is minimal, and a water softener would be overkill. Daly City is softer than 80% of US cities. If you're thinking about water treatment, contaminant filtration is where to focus your money, not softening.
Contaminants & Safety
Lead levels deserve attention. At 7.1 ppb, Daly City is above the ideal of zero, though below the EPA action level of 15 ppb (dropping to 10 ppb in November 2027 under the Lead and Copper Rule Improvements). The lead typically comes from aging service lines or interior plumbing, not the treatment plant. A point-of-use filter certified for lead at the kitchen faucet is a practical safeguard, especially in older homes.
What's in the Treatment Process
Daly City's surface water supply requires heavy chlorination to stay safe — but that creates a tradeoff. The treatment process generates disinfection byproducts: TTHMs at 33.8 ppb (42% of the legal limit, but 226x the EWG guideline) and HAA5 at 36.2 ppb (60% of the legal limit, but 362x the EWG guideline). These are within legal limits, but the EWG sets much tighter thresholds based on cancer-risk research. A whole-house activated carbon filter reduces both chlorine and byproducts.
Chromium-6 was detected at 4.84 ppb, which is 242x the EWG health guideline. There's no separate federal limit for chromium-6, only total chromium. A reverse osmosis system is the most effective removal method. All measurements are within federal legal limits. The EWG guidelines represent a more conservative, health-based standard.
| Contaminant | Detected | Health Guideline | Legal Limit | Status |
|---|---|---|---|---|
| Hardness (as CaCO₃) | 34 PPM | < 60 PPM | No federal limit | ✓ OK |
| Total Dissolved Solids | 55 PPM | < 300 PPM | 500 PPM | ✓ OK |
| PFAS (total) | 0 ppt | — | No total limit | ✓ ND |
| ↳ PFOA | 0 ppt | 0 ppt | 4 ppt (2024) | ✓ OK |
| ↳ PFOS | 0 ppt | 0 ppt | 4 ppt (2024) | ✓ OK |
| Lead | 7.1 ppb | 0 ppb (no safe level) | 15 ppb (10 ppb in 2027) | ⚠ Elevated |
| Chlorine / Chloramine | 0.7 mg/L | Taste threshold ~1.0 | 4.0 mg/L | ✓ Normal |
| Nitrate | 3.08 mg/L | 5 mg/L | 10 mg/L | ✓ OK |
How to Test Your Water in Daly City
Lead enters water from your home's plumbing, not the treatment plant — so Daly City's city-wide average of 7.1 ppb may not match your tap. Testing your specific faucet is the only way to know. Run cold water for 30 seconds before collecting a sample.
Free option: Request City of Daly City's annual Consumer Confidence Report for official city-level data.
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About Daly City's Water Supply
Water Utility: City of Daly City
Water Source: SFPUC Hetch Hetchy (Surface Water)
Population Served: 104,901
Hardness: 34 PPM (2 grains per gallon)
Daly City's drinking water comes from surface sources — SFPUC Hetch Hetchy. Surface water requires more extensive treatment than groundwater, including coagulation, filtration, and disinfection. This heavier chlorination is why disinfection byproducts tend to be higher in surface-supplied systems. On the upside, surface sources often deliver softer water than deep aquifers. The system serves 105,000 residents.
Water quality can vary by neighborhood and season. For your exact numbers, request City of Daly City's Consumer Confidence Report (CCR) or test your own tap.
ZIP Codes Covered by This Report
This water quality data applies to all areas served by City of Daly City in Daly City, CA, including ZIP codes:
94002, 94005, 94010, 94011, 94014, 94015, 94016, 94017, 94018, 94019, 94030, 94037, 94038, 94044, 94066, 94080, 94083, 94401, 94402, 94403, 94497
If your ZIP code is listed above, this report covers your water supply. Water quality may vary slightly by neighborhood.
Compare Daly City to Other California Cities
Frequently Asked Questions About Daly City Water
Is Daly City tap water safe to drink?
Where does Daly City's water come from?
Do I need a water softener in Daly City?
What water filter is best for Daly City?
Is Daly City water safe for babies and infants?
What are disinfection byproducts in Daly City's water?
Is chromium-6 in Daly City's water?
Can I drink Daly City tap water straight from the faucet?
Data sources: Lead and copper data from EPA Safe Drinking Water Act LCR reporting. Contaminant data from utility-reported testing results. PFAS data from EPA UCMR5 (2023–2025). Hardness from USGS and municipal reports. Data reflects system-level testing results and may not match your specific tap due to neighborhood plumbing, season, or recent utility changes. For your utility's latest results, request their Consumer Confidence Report (CCR). Our methodology. Last updated: 2026-02-24.
What Daly City Homeowners Actually Buy
Common purchases for homes with 34 PPM water.
Affiliate disclosure: we may earn a commission. Selection based on Daly City's water data.