Humboldt C.s.d.
EPA ID: CA1210009 · 19,807 people served · 7 ZIP codes
ZipCheckup's reading of EPA records for Humboldt C.s.d. (CA1210009): no drinking-water violations recorded since 2021. Searching the federal compliance records for Humboldt C.s.d. turns up no EPA violations in any contaminant category the file covers; the utility's service area includes approximately 19,807 residents.
Data: EPA SDWIS
Service Area Map
Coverage area for Humboldt C.s.d. Source: EPA SDWIS service area boundaries.
Service area boundary
Demographics of ZIP Codes Served
The ZIP codes associated with Humboldt C.s.d. have a median household income of $76,116 and about 74,340 residents live in those ZIP codes (Census; not the number of people this system supplies). Approximately 75% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
Humboldt C.s.d.'s water is classified in EPA records as a groundwater source. Groundwater is naturally filtered through rock and soil, but it can be vulnerable to PFAS contamination, nitrates from agriculture, and industrial chemicals that seep into the water table.
Infrastructure Risk
Comparable Water Systems
Similar-sized systems in California
System Overview
Humboldt C.s.d. (EPA ID: CA1210009) is a community water system in California that serves approximately 19,807 people from groundwater sources.
This system provides water to 7 ZIP codes across 6 communities.
Violation History
Lead & Copper
EPA Lead and Copper Rule evidence attributed directly to this water system:
| Lead Level | Exceeds Action Level | Sample Date |
|---|---|---|
| 0.0021 mg/L | No | 2025-12-31 |
No copper action-level exceedance record appears for this PWSID in the accepted LCR snapshot. This does not establish a clean copper measurement.
Need help with your water quality?
Typical cost: Water test: typically $20–$50 (DIY kit) · Professional inspection: $150–$400
Find the Right Water FilterFree tip: Ask your water utility whether running cold water for 2 minutes is enough to flush your plumbing before drinking.
ZIP Codes Served
Coverage: Service area ZIP codes sourced from EPA Community Water System Service Area Boundaries v3 (March 2026 release). These ZIPs reflect the actual deployment footprint recorded by CA or modeled from parcel and building-footprint data.
- 95501 - Eureka
- 95503 - Eureka
- 95521 - Arcata
- 95524 - Bayside
- 95537 - Fields Landing
- 95549 - Kneeland
- 95551 - Loleta
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for Humboldt C.s.d. (CA1210009) on EPA.gov.
Frequently Asked Questions
Is Humboldt C.s.d. water safe to drink?
The accepted 2026Q2 ECHO snapshot contains zero violation records for Humboldt C.s.d. in the inclusive 2021-2026 record-year window. This is a compliance-record finding, not a guarantee about water at a specific tap.
How many people does Humboldt C.s.d. serve?
Humboldt C.s.d. serves approximately 19,807 people across 7 ZIP codes in California.
Where does Humboldt C.s.d. get its water?
The primary water source is groundwater.
Federal UCMR5 PFAS Monitoring: No PFAS Reported Above Reporting Levels
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were reported above UCMR5 minimum reporting levels.
EPA's April 2024 PFAS rule sets MCLs of 4 ppt for PFOA and PFOS and 10 ppt for PFHxS, PFNA and HFPO-DA (GenX); water systems must comply from 2029. Other PFAS compounds have no individual federal MCL. A state standard is shown only where this system's state has its own enforceable PFAS limit. Detection results are EPA UCMR5 samples, not a measurement at your tap.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
Frequently Asked Questions
How to cite this page
ZipCheckup. (n.d.). Humboldt C.s.d., CA: Serves 20K People. https://zipcheckup.com/water-system/ca1210009/
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