Bridge & Infrastructure Scanning in Kensington, CA

Kensington carries no state highway and almost nothing the public would call a bridge. Its structures are the ones that make a road possible on a 25 percent slope: retaining walls on the uphill and downhill sides of Arlington Avenue and the lanes that branch off it, cross culverts and storm drains beneath those roads, headwalls and outfalls that discharge into back yards, and the cut and fill slopes the whole community sits on. Because Kensington is unincorporated, that inventory belongs to Contra Costa County Public Works, which maintains more than 660 miles of road and roughly 150 miles of streams, channels, and drainage countywide, and runs a bridge preventative maintenance program alongside the federal Highway Bridge Program for larger structures elsewhere in the county. A job like the storm drain repair the county carried out on Arlington Avenue between Coventry Road and Amherst Avenue is the normal shape of a Kensington structure project: short, tight, and in a road with no shoulder and nowhere to stage.

Scanning suits that setting because the instrument does not need room. We set and observe a control network with GNSS and total station, adjust it by least squares on NAD83 State Plane and NAVD88 with independent checks, and register every Trimble scan position into it, reporting residuals. From compact tripod positions on the pavement, a driveway, or a stairway, each setup returns millions of survey-grade points. Out of that come wall face and batter profiles, top-of-wall and toe elevations at any station, drain inlet and outfall geometry, headwall dimensions, and a bare-earth slope surface with the ivy and oak canopy filtered out. Rescanning later on the same network gives a whole-surface comparison rather than a handful of prism points, which is how wall rotation and slope creep get quantified instead of argued about.

Deliverables are the registered cloud in E57 or RCP, DWG or DXF sections and profiles, and displacement reports. See infrastructure scanning, Kensington 3D scanning, and deformation monitoring.