777 Castle Rock Rd
Walnut Creek 94598 · Unincorporated Contra Costa · Coordinates: 37.90226, -122.00449
Parcel & Assessor
- Lot size:
- 63,877 sq ft (1.47 ac)
- Assessor use:
- Single Family, 1 residence on 1 site, with or without
- Tax rate area:
- 79108
- Addresses on lot:
- 777 CASTLE ROCK RD
Zoning & Land Use
R-40 — Single Family Residential (Unincorporated Contra Costa)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R-40 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R-40, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R-40, a single-family residential zone. The lot is 63,877 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- High Fire Hazard Severity Zone (Local Responsibility Area) (all of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06013C0294G, effective March 21, 2017
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,297,000 – $1,755,000 · Status: Off market
HUD Small Area FMR (ZIP 94598) · FY 2026
Studio $2,850 · 1BR $3,180 · 2BR $3,880 · 3BR $4,960 · 4BR $5,880
Nearby Activity (½ mile radius, since —)
2 active or recent development projects (2 housing units across completed, permitted, and pipeline stages) and 0 total building permits recorded within ½ mile.
Developments Deserving Closer Investigation & Active Area Builders
- New home (Issued)On this parcel
Active in "Issued" for 2 yr (first record Oct 31, 2024) with no new permit activity recorded in 2 yr.
- New home (Entitled)0.14 mi NE
Active in "Entitled" for 5.6 yr (first record Mar 30, 2021) with no new permit activity recorded in 5.6 yr.
- New home (Issued)0.14 mi NE
Active in "Issued" for 5.6 yr (first record Mar 30, 2021) with no new permit activity recorded in 5.6 yr.
- New home (Issued)0.14 mi NE
Active in "Issued" for 5.6 yr (first record Mar 30, 2021) with no new permit activity recorded in 5.6 yr.
Permit & Project History on This Parcel (0 permits, 2 grouped projects)
No building permits recorded on this parcel in our dataset.
State HCD Housing Element APR records on this parcel: 3 entries (report years 2024, 2025).