Seaside, CA Water Safety: 83/100 (2026)
1 ZIP code · 4 water systems · Updated 2026-06-03
Across Seaside, EPA monitoring data shows low violation rates and healthy safety margins — a pattern that places the city well above CA's average for drinking water compliance across recent reporting cycles.
How Seaside Compares
Data: EPA SDWIS Last verified: 2026-06-03
Seaside Water: The Quick Version
- Average lead level: 0.0024 mg/L.
- Homes built before 1986: 75% — older plumbing may contain lead solder.
- Estimated remediation: $3,500 per household.
- CDC health risk index: 11.65.
Water Systems Serving Seaside
3 water utilities share the residential service territory in Seaside, CA — out of 4 total systems in federal records.
Overview
We track water quality and home safety data for 1 ZIP code in Seaside, California (population ~32,253), covering 4 community water systems serving approximately 133,977 people region-wide.
No EPA violations recorded across any ZIP codes in Seaside — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Seaside: B (83/100)
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
Seaside water systems draw from: Groundwater.
Lead & Copper
- Average lead level (90th percentile): 0.0024 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 93955 | B | Seaside Municipal Water System | 2,800 |
All ZIP Codes in Seaside
- 93955 [B]
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 Seaside
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 Seaside's Housing Stock?
With 75% 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
While newer cities carry lower aggregate plumbing risk from lead-era construction, Seaside sits firmly in the older category. The median build year of 1962 indicates that more than half the housing stock was built before 1986, when lead solder was still legally used in residential copper plumbing — and a substantial portion likely predates 1970, when lead pipes were still commonly installed for service lines. These two thresholds together define the elevated plumbing risk environment that older housing cities carry, independent of what the municipal water supply delivers to the meter.
Over half of homes in Seaside 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.
Seaside: Remediation Cost in Perspective
How much of a Seaside home's value does documented remediation represent? A small fraction — the equity share here is in the low tier, and from a household financial perspective, most property owners are considering a commitment that fits comfortably within standard planning rather than a decision that rises to the level of a material budget event or significant equity consideration.
Remediation costs in Seaside are relatively low compared to home values. The $2,200–$5,600 estimated range is a small fraction of median property value. Home values are 6% below the California average.
Protecting Children from Lead in Seaside
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.
Reading the local data together points toward a structural gap that matters more here than in low-exposure communities. 75% of Seaside stock comes from the pre-rule era, and citywide monitoring either approaches or sits beyond the federal benchmark under Lead and Copper Rule sampling. A baseline kit fits the routine-diligence category, with certified filtration available via retailer networks where confirmed faucet results warrant additional measures.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Seaside
Taken together, Seaside's 2 NFIP flood insurance claims and 100% FEMA flood zone coverage place it in the moderate range of exposure. That middle position has specific implications for water quality. The contamination pathways that flooding can open — surface water overwhelming treatment facility intake, floodwaters infiltrating private wells, distribution pressure changes creating backflow — are not constant risks in a moderate-exposure community. But they do become active during significant flood events, and the claim record here indicates enough of those events to make flood timing an occasional factor in local water quality conversations.
Seaside has a moderate flood history with 2 FEMA claims averaging $62,516 per payout. 100% 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>$3,500</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.
Deep Dive Reports
Detailed analysis for Seaside, CA