Rowland Water District
EPA ID: CA1910194 · 54,660 people served · 7 ZIP codes
Federal monitoring records confirm Rowland Water District has operated without any EPA violations for the full five-year window — covering every contaminant category and reporting cycle across a service area of approximately 54,660 residents, with no gaps in the compliance record.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Rowland Water District Source: EPA SDWIS service area boundaries.
Service area boundary — Grade B
Service Area Demographics
The Rowland Water District serves a community with a median household income of $102,208 and an estimated 361,634 residents across its service area. Approximately 81% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: 45% of the population in this service area is classified as disadvantaged under EPA's EJScreen criteria. Communities with higher disadvantaged populations often face disproportionate environmental and health burdens, including aging water infrastructure and limited resources for remediation.
🌊 Where Does Your Water Come From?
Rowland Water District's water is drawn from rivers, lakes, or reservoirs. Surface water sources are more exposed to agricultural runoff, stormwater, and upstream discharges, but they typically receive more intensive treatment before reaching your tap.
About 2% of homes in Orange County, California rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Superfund Proximity Note: This service area ranks in the 69th percentile nationally for proximity to Superfund (NPL) sites.
Infrastructure Risk
PFAS Detected in Service Area
PFAS ("forever chemicals") have been detected in water serving this system's area. 31 detections recorded. 3 exceed federal EPA limits (4 ppt for PFOA/PFOS). 2 exceed state limits.
Comparable Water Systems
Similar-sized systems in California
Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
Rowland Water District (EPA ID: CA1910194) is a community water system in California that serves approximately 54,660 people from surface water sources.
This system provides water to 7 ZIP codes across 7 communities.
Average Home Safety Score: B (75/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Lead & Copper
No Lead and Copper Rule sampling data available for this water system.
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 2 (Moderate Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
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: Let cold water run for 2 minutes before drinking — this helps flush lead from your pipes.
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.
- 90631 — La Habra
- 91744 — La Puente
- 91745 — Hacienda Heights
- 91748 — Rowland Heights
- 91765 — Diamond Bar
- 91789 — Walnut
- 91792 — West Covina
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Rowland Water District (CA1910194) on EPA.gov.
Frequently Asked Questions
Is Rowland Water District water safe to drink?
Based on EPA records, Rowland Water District has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does Rowland Water District serve?
Rowland Water District serves approximately 54,660 people across 7 ZIP codes in California.
Where does Rowland Water District get its water?
The primary water source is surface water.
Federal UCMR5 PFAS Monitoring: Detected
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). PFAS compounds were detected below the current state-enforceable MCL.
Current MCL reflects the lowest state-enforceable limit (NYS 10 ppt for PFOA/PFOS, effective August 2020). The federal final MCL of 4 ppt for PFOA/PFOS (EPA April 2024 rule) is not enforceable until April 2029. Detections above 4 ppt but below 10 ppt are below current MCL but above the future federal limit.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
This system reports zero confirmed lead service lines in its inventory. Unknown-material counts may still warrant verification.
Federal LCRI rule (effective October 2024) requires every public water system to inventory its service lines and complete lead-line replacement within 10 years.
Source: EPA SDWIS Federal Service Line Inventory (Phase 2) · Submitted 2026
ZipCheckup is not affiliated with the utility or state agency. Inventory figures render verbatim from the public LCRI submission cited above; ZipCheckup does not perform inspections or replacements.