312 Seadrift Rd
Stinson Beach 94970 · Stinson Beach · Unincorporated Marin · Coordinates: 37.90680, -122.67379
Executive Verdict · Public-Records Synthesis
Zoned C-RSPS-2.9 in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA VE flood / Alquist-Priolo fault due diligence; benchmark value $3,333,000 ($2,933,000–$3,733,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone C-RSPS-2.9 allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$138,000 contributory est.)
Public building records show issued construction/renovation work on this parcel (4 total permits, latest Jun 21, 2024).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! FEMA Special Flood Hazard Area (VE, about 90% of the lot of lot)
Zone VE: 1% annual chance flood (Special Flood Hazard Area) overlaps this parcel. Expect mandatory flood insurance for federally backed loans and floodplain elevation/mitigation rules for new units or SB 9 applications.
Source: FEMA National Flood Hazard Layer (parcel polygon)
- ! Alquist-Priolo Earthquake Fault Zone (all of the lot of lot)
Intersects a State-mapped surface fault rupture zone. Adding habitable structures or subdividing typically requires a site-specific geologic fault investigation.
Source: California Geological Survey Alquist-Priolo Zones
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: New home at 321 Seadrift Rd (410 ft NW, issued). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
- ! Year 1 Prop 13 tax reset (~$38,780/yr at $3,333,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$3,232/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Parcel & Assessor
- Lot size:
- 16,945 sq ft (0.39 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 312 SEADRIFT RD
Zoning & Land Use
C-RSPS-2.9 — Residential Single Family Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned C-RSPS-2.9 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotPossible, with conditions
Zoned C-RSPS-2.9, a single-family residential zone. Alquist-Priolo Earthquake Fault Zone covers all of the lot: the project must meet the seismic building standards, and a fault study is usually required. FEMA Special Flood Hazard Area (Zone VE) covers about 90% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
- SB 9: split into two lotsPossible, with conditions
Zoned C-RSPS-2.9, a single-family residential zone. The lot is 16,945 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original. Alquist-Priolo Earthquake Fault Zone covers all of the lot: the project must meet the seismic building standards, and a fault study is usually required. FEMA Special Flood Hazard Area (Zone VE) covers about 90% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Not in a State-mapped fire hazard severity zone
- FEMA National Flood Hazard Layer
- Zone VE: 1% annual chance flood (Special Flood Hazard Area) (about 90% of the lot); Zone X: 0.2% annual chance flood hazard (shaded X) (about 10% of the lot) · FIRM panel 06041C0441E, effective August 15, 2017
- CGS Alquist-Priolo Earthquake Fault Zone
- Alquist-Priolo Earthquake Fault Zone (Bolinas quadrangle) (all of the lot)
Surrounding Rent & Value Benchmarks (Public Records)
Range: $2,933,000 – $3,733,000 · Status: Off market
HUD Small Area FMR (ZIP 94970) · FY 2026
Studio $2,090 · 1BR $2,510 · 2BR $3,030 · 3BR $3,870 · 4BR $4,010
Developments Deserving Closer Investigation & Active Area Builders
- New home at 321 Seadrift Rd (Issued)410 ft NW
Active in "Issued" for 3.7 yr (first record Mar 13, 2023) with no new permit activity recorded in 2.8 yr. High-impact scale (1 housing unit, $960,000 declared valuation across 1 permit).
- New home at 285 Seadrift Rd (Issued)0.16 mi E
Active in "Issued" for 9.4 yr (first record Jun 12, 2017) with no new permit activity recorded in 9 yr. High-impact scale (1 housing unit, $900,000 declared valuation across 1 permit).
- New home at 342 Seadrift Rd (Issued)0.17 mi W
Active in "Issued" for 8 yr (first record Nov 8, 2018) with no new permit activity recorded in 7.8 yr. High-impact scale (1 housing unit, $1,200,000 declared valuation across 1 permit).
- New home at 177 Dipsea Rd (Issued)0.27 mi E
Active in "Issued" for 12.8 yr (first record Jan 16, 2014) with no new permit activity recorded in 12.3 yr. High-impact scale (1 housing unit, $1,452,000 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Boyce Construction (1 on parcel, 1 in ½ mi · Remodel / interior alteration); Murphy Roofing Consulting (1 on parcel, 1 in ½ mi · Roof replacement); Boyce Electric (1 on parcel, 1 in ½ mi · Electrical / panel); Robert W Von Ahn Plumbing And Electrical Contractor (1 on parcel, 1 in ½ mi · Electrical / panel); Gubbins Building (10 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (4 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 176909 | Remodel / interior alteration | Issued | Iss. Jun 21, 2024 | $550,000 | Remodel; Siding; Skylight; Windows & Doors |
| B36256 | Electrical / panel | Issued | Iss. Nov 29, 2023 | $1,000 | Replacement of existing meter socket. Install new meter panel with 200 amp circuit breaker. — Service Upgrade |
| B13731 | Roof replacement | Issued | Iss. Nov 14, 2017 | $6,000 | Tear off and hot mop. Class A comp to be installed. — ReRoofing |
| 147963 | Electrical / panel | Issued | Iss. Jul 13, 2015 | $2,000 | Repl Main Panel No Amperage Change ***Refund Prepared 7/31/15 |