ADU Surveys in Crockett, CA

Crockett is unincorporated, so its ADU applications go to Contra Costa County under the standard county checklist — property lines with dimensions, easements, all structures with setbacks, water and sewer locations for detached units, trees over 20 inches in circumference within 50 feet of construction, grant deed with legal description — and the county's slope-based geotechnical trigger rides along: a report may be required where the site slopes more than 5 percent, with exemption only below roughly 25 percent on ground without a soils history. Crockett's terrain makes that trigger nearly universal. The old C&H Sugar company town is stacked on terraces cut into the hillside above the Carquinez Strait, with streets switchbacking between rows of early-1900s workers' cottages, and the flat spots on most lots were made, not found — held up by generations of retaining walls in every state of repair.

That terracing defines the ADU problem here. A buildable pad usually means engaging an existing wall or building a new one, drainage has to be routed down a slope shared with neighbors, and the backyard's usable depth depends on where the terrace edge — and the legal line — actually fall. The 1900s-era grid was monumented sparsely and the cottages predate modern setback thinking, so record lines and occupation have had a century to diverge. Our laser-scanned site survey captures the whole terraced section in one visit: boundary resolved from county records, walls with top- and bottom-of-wall elevations, dense contours through the vegetation, and the structures above and below that hillside design has to respect. Where the inspector requires verification that foundation forms match approved setbacks before the pour, the same boundary work closes it out in a short return trip.

Records run through the Contra Costa County Recorder in Martinez. Deliverables are a stamped base map, layered DWG, and staked corners; for terrain-led scope see our Crockett topographic surveys.