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Riverdale Park, CA Tap Water Quality 2026

Water quality report for Riverdale Park, CA — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at Riverdale Park's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: Riverdale Park Tract Csd PWSID: CA5000019 Updated: 2026 Q2
✅

No federal limits exceeded on record

Lead is 5.00 ppb, 33% of the action level and no violations are open. PFAS has never been sampled at this system.

B

Riverdale Park earns a B for water quality

Graded on violations and lead, with state inspection findings. PFAS not tested.

Lead: 5.00 ppb — 33% of the federal action level
PFAS never sampled at this system
8 violations since 2015, 6 health-based
No violations currently open
Riverdale Park's lead level vs. all California community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: 5.00 ppb — 33% of the federal action level
✓ Lower lead than 18% of California utilities
Population Served
764
~180 connections
Water Source
Groundwater
Drawn from wells — SDWIS source code GW
Active Violations
0
8 since 2015, all resolved

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
33% of EPA action level
5.00 ppb
Action level: 15 ppb
The 90th-percentile lead result is 5.00 ppb, 33% of the 15 ppb federal action level. The action level is a treatment trigger, not a legal maximum, and it is measured across sampled taps rather than at any single home.

Contaminant Violations (2015–Present)

ContaminantTypeMeasuredLimitPeriodStatus
Combined Uranium MONITORING AND REPORTING — 30 ug/L 2024 Archived
Combined Uranium MONITORING AND REPORTING — 30 ug/L 2024 Archived
Combined Uranium MCL EXCEEDANCE 21 PCI/L 30 ug/L 2020 Archived
Combined Uranium MCL EXCEEDANCE 21 PCI/L 30 ug/L 2016 Archived
Combined Uranium MCL EXCEEDANCE 21 PCI/L 30 ug/L 2016 Archived
Combined Uranium MCL EXCEEDANCE 22 PCI/L 30 ug/L 2016 Archived
Combined Uranium MCL EXCEEDANCE 22 PCI/L 30 ug/L 2015 Archived
Combined Uranium MCL EXCEEDANCE 23 PCI/L 30 ug/L 2015 Archived
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

8 violations are on record since 2015, of which 6 were health-based. All have been resolved and none remain open.

About the Main Water System

Utility Riverdale Park Tract Csd
PWSID CA5000019
Water source Groundwater — Drawn from wells — SDWIS source code GW
Population served 764
Service connections 180
Systems serving this area 2
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is Riverdale Park tap water safe to drink? ▼
No federal limit is exceeded on record. No violations are currently open. Lead is 5.00 ppb, 33% of the action level.
Does Riverdale Park water have PFAS? ▼
This system has never been sampled for PFAS. EPA's national monitoring covered systems serving 3,300 people or more, so no results exist — which is not evidence that none is present.
Who supplies water to Riverdale Park? ▼
Riverdale Park Tract Csd (PWSID CA5000019), one of 2 systems serving this area. Groundwater. Drawn from wells — SDWIS source code GW
When was this system last inspected? ▼
It was last inspected on 2025-04-03. No significant deficiencies were recorded.

What Should Riverdale Park Residents Do?

1
Consider a filter certified for lead
Look for NSF/ANSI 53 certification for lead reduction.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Flush before drinking
If water has sat in pipes more than six hours, run the cold tap for two minutes before drinking or cooking.

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