This property is served by an official Standard OWTS onsite septic system registered under Permit #OWTS-155-260-010 with the Sonoma County health department.
The permitted system is engineered for 3 bedrooms with an approved 1,000-gallon tank capacity.
System details
System typeStandard OWTS
Permit statusActive / Approved
Tank capacity1,000 Gallons
Approved bedrooms3 Bedrooms
Design daily flow360 gal/day (CA Health Code)
Tax Parcel ID155-260-010
Soil ClassificationPermit Sonoma Soil Survey
Supervising AgencyPermit Sonoma - Well & Septic Division
Public Record Notice & Schematic Blueprint Disclaimer:
This technical drawing is an illustrative layout model depicting typical Sonoma County (California) setback geometry (house, 100-ft well buffer, 10-ft property boundary clearances) for a 3-bedroom / 1,000-gal system. It is NOT the surveyed blueprint of this specific property. Exact physical triangulation distances from house corners are preserved in the original hand-drafted inspection file (Permit #OWTS-155-260-010) on file with Permit Sonoma - Well & Septic Division.
Official Permit #OWTS-155-260-010 on fileVerified compliant with California residential health code
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📍 35509 Timber Ridge Rd, Sonoma County, CAResolving parcel coordinates...
Sanitary Setback Standard: Under California environmental health code, all septic absorption drainfields must observe a minimum horizontal separation of 100 feet from any private drinking water well heads and 10 feet from property boundaries.
Quick Field Tank Locator
Sonoma County • CA Field Standard
Use this quick 4-step checklist to pinpoint your underground tank lids in the yard before routine pumping or inspection.
1
Trace Foundation Sewer Exit Line
Locate the 3-inch or 4-inch main DWV waste pipe exiting the basement, crawlspace, or bathroom exterior foundation.
Under gravity standards, the tank inlet lies along a straight line projected perpendicular from this foundation exit point.
2
Spot 4-Inch Cleanout & Setback Vector
Look for a threaded 4" PVC cleanout cap 3 to 5 feet outside the house foundation wall.
Setback (California Onsite Wastewater Regulations): Requires minimum 8-ft foundation clearance. Installers typically set the tank 10 to 20 feet away along this cleanout axis.
3
Check Turf Outline & Estimated Footprint
For this 1,000-gallon tank, expect an underground footprint of approx. 5 × 8 ft at 12–36 inches depth.
Summer / Dry Spell: Grass directly over shallow tank lids dries and yellows faster than surrounding lawn.
Winter / Frost: Bacterial warmth (50°–60°F) inside the tank melts snow and morning frost premature to the yard.
4
Non-Destructive Soil Probing Feedback
Using a blunt-tip steel T-handle probe, insert every 12 to 18 inches starting 10 ft out from your cleanout.
Lid Contact: Unyielding solid "thud" across a continuous approx. 5 × 8 ft horizontal span.
Rock vs. Root: Rock produces sharp scratch deflection; tree roots yield with a spring-back bounce.
Compliant with California Onsite Wastewater Regulations (8-ft foundation setback)Never drive vehicles or heavy equipment over the tank or drainfield corridor
Need in-depth field guidance or electronic locating?
Read our complete technical guide on flushable radio transmitters (sondes), as-built triangulation, and modern surface riser retrofits.
Under California Government Code § 4216 (USA North 811 / DigAlert): Always call 811 two full business days before inserting steel probes or excavating. Private septic lines are not marked by 811, but public utility clearance is legally mandatory.
Pumping & maintenance guidance
EPA Pumping Frequency & Maintenance Calculator
EPA Standard (Pub. 832-F-12-001)
✓ Verified on Permit #OWTS-155-260-010
4 People
Estimated from 3-bedroom permit
Receipt kept by owner / contractor
EPA Recommended Service Interval
Every 3 to 4 Years
Service Status
Select Year to Check Status
EPA Regulatory Requirement (The 1/3 Rule): Regardless of calendar years, a septic tank must be pumped whenever the floating scum layer comes within 6 inches of the outlet baffle or accumulated bottom sludge exceeds 30% to 33% of the liquid depth. Standard gravity systems require professional inspection every 1 to 3 years.
Under California State Water Resources Control Board OWTS Policy, routine septic tank cleanouts are performed by privately contracted, state-licensed septic tank contractors. Routine pump-out receipts are maintained by the property owner and the service company. For a 1,000-gallon tank supporting a 3-bedroom residence, state environmental health guidelines recommend the following pumping intervals:
Household OccupancyRecommended Interval
1 to 2 occupantsLight household water usage
Every 4 – 5 years
3 to 4 occupantsStandard residential usage
Every 3 – 4 years
5+ occupantsHeavy usage or garbage disposal equipped
Every 2 – 3 years
💡 Inspection Tip: Never allow heavy equipment or vehicles to drive over your 1,000-gallon tank or drainfield absorption area.
Property Septic Disclosure & Escrow Summary
Standard Real Estate Closing & Due Diligence Form (Form PSD-2026)
OFFICIAL SANITARY PUBLIC RECORD COMPILATION
PROPERTY SEPTIC DISCLOSURE & ESCROW SUMMARY
Prepared for Real Estate Due Diligence, Title Transfer, Escrow Closing & Home Inspection
Report ID: PSD-CA-OWTS155260010
Date Certified: October 5, 2026
Authority: CA Onsite Records
1. REAL PROPERTY & PUBLIC HEALTH JURISDICTION
Property Street Address:35509 Timber Ridge Rd
Parcel Identification (APN):155-260-010
Subdivision / Legal Lot:SINGLE FAMILY DWELLING
County & State:Sonoma County, CA
Regulating Health Department:Permit Sonoma - Well & Septic Division
Department Phone / Office:(707) 565-1900 • 2550 Ventura Ave, Santa Rosa, CA 95403
3. STATUTORY SETBACK REQUIREMENTS (CA SANITARY CODE)
100 FTDrinking Water Well
10 FTProperty Boundary
8 FTBuilding Foundation
100 FTSurface Water / Stream
Notice: Siting and setback distances must be maintained free of permanent structures, driveways, patios, or swimming pool construction.
4. AS-BUILT DRAWING & PUBLIC RECORDS AUDIT
✓ Official Digital As-Built Drawing On File
A verified technical as-built plot plan is attached to this record in the environmental health repository. The drawing details the precise location of the septic tank, inlet/outlet baffles, header pipe, and subsurface absorption drainfield lines.
5. EPA PUMPING GUIDANCE & LOCAL MAINTENANCE COSTS (PUB. 832-F-12-001)
U.S. EPA Service Interval Standard
• Cleanout Frequency: Every 3 to 5 years for standard gravity systems.
• The 1/3 Rule: Tank must be pumped whenever accumulated bottom sludge and floating scum exceed 30% to 33% of liquid depth, regardless of calendar years.
• Routine Inspection: Annual to triennial professional inspection recommended.
Typical Sonoma Contractor Rates
• Routine Pump-Out:$450 – $850 (average 1,000 gal).
• Full Replacement Cost: $12,000 – $28,000.
• Receipt Retention: Receipts must be retained by property owner.
6. ESCROW & TITLE DUE DILIGENCE CHECKLIST (BUYER / SELLER AUDIT)
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1. Maintenance Log & Pumping Receipts: Seller to provide verified receipts from licensed septic service company covering past 3 to 5 years.
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2. Professional Pre-Closing Inspection: Buyer advised to commission independent inspection (hydraulic dye test, tank baffle inspection, and drainfield camera scope).
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3. Bedroom Capacity Verification: Verify residence does not contain unpermitted bedrooms exceeding the approved 3-bedroom limit (excess occupants cause premature drainfield saturation).
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4. Surface Clearances & Risers: Verify tank access lids and effluent filter risers are secured to grade, undamaged, and clear of soil obstruction.