Monument Preservation in El Sobrante, CA

El Sobrante is unincorporated, which means its streets are county-maintained and its permits run through Contra Costa County rather than a city hall. That has a practical consequence for monument preservation: when the county or its contractors repave San Pablo Dam Road, replace a culvert, or trench for utilities on a valley side street, the survey monuments in those roads are protected by Business and Professions Code §8771, and the Corner Records that document them are filed with the Contra Costa County Surveyor in Martinez. On El Sobrante's semi-rural blocks — larger lots, horse properties, creek-adjacent parcels — monuments are often widely spaced, so each one that survives controls more boundary than it would in a dense subdivision. Losing a single monument here can unsettle the corners of many acres.

Our process as licensed land surveyors is to locate every monument within the work limits before construction, set durable reference ties well outside the disturbance zone, and file a Corner Record for each monument with the County Surveyor. After grading, paving, or trenching is complete, we return, reset each monument in its original position from our references, and file the post-construction Corner Record that closes the loop. Where the work corridor is long — a road-widening or overlay job running down the valley — our Trimble terrestrial laser scanner captures the entire corridor at survey grade in one pass, documenting monuments, pavement, fences, and creek crossings together so nothing within the limits goes unrecorded.

For contractors bidding county road work in El Sobrante, building monument preservation into the bid is far cheaper than the alternative. Re-establishing a destroyed monument on an older metes-and-bounds parcel can require days of record research and field retracement; referencing and resetting it under §8771 is a fraction of that cost, and it keeps the project compliant with state law.