City of Petaluma
EPA ID: CA4910006 · 60,781 people served · 9 ZIP codes
Federal compliance records for City of Petaluma list 2 open violations that have not yet been resolved — the utility serves approximately 60,781 people, and each outstanding finding remains logged and active in the EPA enforcement database.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for City of Petaluma Source: EPA SDWIS service area boundaries.
Service area boundary — Grade A
Service Area Demographics
The City of Petaluma serves a community with a median household income of $108,322 and an estimated 119,426 residents across its service area. Approximately 65% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
City of Petaluma's water is pumped from underground aquifers. 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.
About 1% of homes in Sonoma County, California rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Infrastructure Risk
Detected Contaminants
How City of Petaluma compares to EPA limits
What This Means For You
Stage 2 DBP Rule at 2 mg/L exceeds the EPA maximum of mg/L.
Stage 1 DBP Rule at 1 mg/L exceeds the EPA maximum of mg/L.
PFAS Detected in Service Area
PFAS ("forever chemicals") have been detected in water serving this system's area. 6 detections recorded. 2 exceed federal EPA limits (4 ppt for PFOA/PFOS). 1 exceeds 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
City of Petaluma, (EPA ID: CA4910006) is a community water system in California that serves approximately 60,781 people from groundwater sources.
This system provides water to 9 ZIP codes across 4 communities.
Average Home Safety Score: A (86/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| October 17, 2024 | Stage 2 DBP Rule | Monitoring | Unresolved |
| October 17, 2024 | Stage 2 DBP Rule | Health-based | Unresolved |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Stage 2 DBP Rule | Treatment Failure | 2 | Yes |
| Stage 1 DBP Rule | Treatment Failure | 1 | No |
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 94951 | 0.0185 mg/L | Yes | N/A |
| 94952 | 0.00043 mg/L | No | N/A |
| 94953 | 0.00043 mg/L | No | N/A |
| 94954 | 0.00043 mg/L | No | N/A |
| 94955 | 0.00043 mg/L | No | N/A |
| 94975 | 0.00043 mg/L | No | N/A |
| 94999 | 0.00043 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 3 (Low Risk)
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: 5 ZIP codes confirmed via EPA Community Water System Service Area Boundaries v3 plus 4 additional ZIPs inferred from SDWIS registry data. The EPA-confirmed set is the most reliable; SDWIS-inferred entries may be narrower than the real deployment area.
- 94931 — Cotati
- 94951 — Penngrove
- 94952 — Petaluma
- 94953 — Petaluma
- 94954 — Petaluma
- 94955 — Petaluma
- 94975 — Petaluma
- 94999 — Petaluma
- 95476 — Sonoma
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for City of Petaluma (CA4910006) on EPA.gov.
Frequently Asked Questions
Is City of Petaluma water safe to drink?
City of Petaluma has recorded 1 health-based violation in the past 5 years. While the system is required to treat water to meet federal standards, you may want to consider additional precautions such as a certified water filter.
How many people does City of Petaluma serve?
City of Petaluma serves approximately 60,781 people across 9 ZIP codes in California.
Where does City of Petaluma get its water?
The primary water source is groundwater.
Contact Your Water Utility
Public-record contact information for the water utility serving this system. Use these channels to request water quality reports, ask about service, or report issues directly.
Contact information from City of Petaluma Department of Water Resources and Conservation Consumer Confidence Report.
ZipCheckup is not affiliated with this water utility, does not act as its agent, and does not provide customer support for it. Contact details shown are public-record information from CCR filings. For service issues, contact the utility directly using the information above.
Water Source & Treatment
Where this water originates and how it's treated before reaching your tap.
Source: City of Petaluma Department of Water Resources and Conservation Consumer Confidence Report.
ZipCheckup is not affiliated with this water utility. Treatment and source data are sourced from the utility's published CCR filings.
An assessment of the drinking water sources for the City of Petaluma was completed in March 2003. The sources for the City of Petaluma are considered most vulnerable to the following activities: sewer collection systems, airport maintenance and fueling areas, known contaminant plumes, and underground storage tanks. The sources for Sonoma Water are considered most vulnerable to wastewater disposal and mining operations.
Treatment regime
How this utility classifies its treatment process and what each reported treatment chemical does.
Treatment chemicals and what each one does
Chemical names are reported verbatim by the utility. Purpose categories are ZipCheckup annotations based on standard drinking-water treatment practice.
Watershed exposure sources reported
Land-use and natural conditions identified in the utility's source-water assessment as potential contamination sources upstream of treatment.
Treatment classification and chemical list sourced from City of Petaluma Department of Water Resources and Conservation Consumer Confidence Report.
Treatment intensity is a ZipCheckup-derived classification based on the chemicals and processes the utility reports. Chemicals and contamination sources are taken verbatim from the utility's CCR filing. Routine federal monitoring and contaminant testing shown elsewhere on this page determine whether the water meets safety standards, not the treatment classification.
Federal UCMR5 PFAS Monitoring: Tested Clean
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were detected.
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 →
PFAS Substances Detected in This System
This water system's Consumer Confidence Report disclosed the following PFAS compounds. Levels are from the utility's most recent reporting cycle.
In April 2024, EPA finalized the first National Primary Drinking Water Regulation for six PFAS. Public water systems have until 2029 to comply. EPA — PFAS regulation overview →
Source: Consumer Confidence Report disclosed by City of Petaluma Department of Water Resources and Conservation.
ZipCheckup is not affiliated with this water utility. PFAS detection data is sourced from public Consumer Confidence Reports filed by the utility itself.
An explanation of our lead service line inventory can be found at cityofpetaluma.org/servicelineinventory/.
Lead Service Line Replacement Tracker
This water utility's lead service line (LSL) replacement program is tracked from public Consumer Confidence Report filings. Email signup notifies subscribers when the utility files an updated replacement plan or progress milestone.
City of Petaluma Department of Water Resources and Conservation
ZipCheckup is not affiliated with this water utility. LSL replacement-program data is sourced from public CCR filings published by the utility. Subscription notifications are based on automated parsing of subsequent CCR releases.
Learn more about Lead and Copper Rule replacement requirements →
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
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.
Aesthetic water quality
These measurements describe the look, taste, and feel of the water this utility delivers. They are not contaminant violations — they sit alongside federal Secondary Maximum Contaminant Levels (SMCLs) which the EPA publishes as non-enforceable guidance.
Aesthetic measurements from City of Petaluma Department of Water Resources and Conservation Consumer Confidence Report.
Aesthetic measurements are reported by the utility from its annual sampling. EPA Secondary MCLs are advisory thresholds — values outside them indicate aesthetic concerns such as taste or appearance, not health violations. Federal contaminant testing is shown in the sections above.
Hard water detected in City of Petaluma Department of Water Resources and Conservation
Your utility reported water hardness of 320 ppm CaCO₃ (18.7 grains per gallon) in its most recent Consumer Confidence Report. This is in the very hard range and may cause scale buildup, reduced appliance lifespan, and dry skin or hair.
There are three common approaches to treating hard water: salt-based ion-exchange softeners (most effective, require salt refills), salt-free conditioners (lower maintenance, scale prevention only), and reverse osmosis at the kitchen sink (cooking and drinking water only). Aquasana, EcoWater, Pelican, and SpringWell are among the major US brands.
Paid Partner. ZipCheckup earns commission on Aquasana purchases. We do not test water or verify product effectiveness for specific hardness levels — manufacturer claims are theirs alone. Consult a certified water-quality professional for personalized advice.
Hardness data parsed from this utility's most recent Consumer Confidence Report. Severity bands per USGS hard water classification.
Frequently Asked Questions
What You Can Do
Test your water
Home test kits can detect lead, bacteria, and other contaminants at your tap. Find the right filter →
Check your specific ZIP code
Water quality can vary within a system. View nearest ZIP report →
Contact your utility
City of Petaluma (EPA ID: CA4910006) — request the latest Consumer Confidence Report or ask about specific contaminants.