Berkeley, CA Water Safety: 60/100 (2026)
11 ZIP codes · 1 water system · Updated 2026-06-03
Compliance figures for Berkeley indicate average water quality in CA overall — some service areas have recorded health-based violations in recent monitoring cycles, while others operate cleanly, making system-level data the most actionable reference point for residents.
How Berkeley Compares
Data: EPA SDWIS Last verified: 2026-06-03
Water Quality Map: Berkeley, CA
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Score Distribution
Distribution of water safety grades across Berkeley.
Berkeley Water: The Quick Version
- Homes built before 1986: 83% — older plumbing may contain lead solder.
- Estimated remediation: $1,736 per household.
- CDC health risk index: 9.77.
Water Systems Serving Berkeley
While 1 water system appear in federal records for Berkeley, CA, one provider supplies the majority of residential connections — making it the central point of infrastructure and compliance accountability for most households.
Overview
We track water quality and home safety data for 11 ZIP codes in Berkeley, California (population ~127,190), covering 1 community water system serving approximately 1,442,800 people region-wide.
No EPA violations recorded across any ZIP codes in Berkeley — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Berkeley: C (60/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Berkeley water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Berkeley
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 11 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 94701 | D | EAST BAY MUD | 1,442,800 |
| 94702 | C | EAST BAY MUD | 1,442,800 |
| 94703 | C | EAST BAY MUD | 1,442,800 |
| 94704 | C | EAST BAY MUD | 1,442,800 |
| 94705 | C | EAST BAY MUD | 1,442,800 |
| 94707 | C | EAST BAY MUD | 1,442,800 |
| 94708 | C | EAST BAY MUD | 1,442,800 |
| 94709 | C | EAST BAY MUD | 1,442,800 |
| 94710 | C | EAST BAY MUD | 1,442,800 |
| 94712 | D | EAST BAY MUD | 1,442,800 |
All ZIP Codes in Berkeley
- 94701 [D]
- 94702 [C]
- 94703 [C]
- 94704 [C]
- 94705 [C]
- 94707 [C]
- 94708 [C]
- 94709 [C]
- 94710 [C]
- 94712 [D]
- 94720 [D]
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
CDC Health Data for Berkeley
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
How Old Is Berkeley's Housing Stock?
With 83% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Plumbing risk in older housing is defined by two eras: the pre-1970 period when lead pipes were commonly used for service lines, and the 1970-to-1986 period when lead solder remained standard in copper plumbing until the federal ban. Berkeley's median build year of 1942 lands in a range where both eras are heavily represented in the housing stock. That creates an elevated aggregate environment for plumbing-related lead exposure — one that city-level water quality averages don't capture, because the risk sits inside individual properties rather than in the distribution system.
Over half of homes in Berkeley were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
Berkeley: Remediation Cost in Perspective
At current valuations, Berkeley sits in the low remediation-share tier — the equity impact of fixing documented issues is proportionally minor.
Remediation costs in Berkeley are relatively low compared to home values. The $864–$2,827 estimated range is a small fraction of median property value. Home values are 72% above the California average.
Protecting Children from Lead in Berkeley
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Older interior plumbing shapes the local picture: 83% of Berkeley homes predate the federal solder ban, and aggregate sampling either approaches or crosses the action benchmark. That mix makes a single-home draw a standard pre-purchase or pre-occupancy step.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Berkeley
The NFIP claim record for Berkeley — 44 filed incidents — reflects genuine, recurring flood exposure rather than an isolated event or two. When a community accumulates flood claims at this volume and carries 73% of its ZIP codes inside FEMA-designated zones, flood history starts to factor into water quality planning in ways it doesn't for lower-exposure areas. Flooding introduces specific contamination pathways — runoff overwhelming treatment facility intake, surface water infiltrating private wells, and pressure disruptions in distribution systems allowing backflow — all of which become more relevant as flood frequency increases.
Berkeley has a moderate flood history with 44 FEMA claims averaging $2,482 per payout. 73% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$1,736</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Berkeley
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. With 83% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Berkeley, CA