If grading, demolition, new construction, utility work, or frontage changes occur after a topographic survey, mark those changes on the dated base map and ask the surveyor and civil designer which areas must be remeasured. The original survey remains a record of conditions at the time of fieldwork. It should not be treated as a current depiction of work completed later.
Identify what changed on the site
Compare the survey date with site photos, demolition records, construction drawings, as-built information, and the field superintendent's account. A resurfaced parking area may affect elevations and drainage. A removed building can reveal features previously inaccessible. A new wall, trench, driveway, or street improvement can change tie-in grades or the design footprint. Ask what changed and where, rather than applying a universal expiration date to every topographic survey.
Draw the limits of the proposed update
Send the surveyor a marked plan showing the changed area and the civil engineer's required features. Confirm whether the update needs spot elevations, contours, curb and gutter, walls, structures, visible utility features, or additional off-site coverage. For projects submitted in Bellevue, compare the proposed scope with the city's boundary and topographic survey requirements. The required coverage depends on the permit and project conditions; a small field revisit is not automatically sufficient.
Keep the old and new measurements coherent
Ask whether the update will use the same horizontal and vertical control, datum, units, and file conventions as the original deliverable. Show the date and limits of the new fieldwork so a designer can distinguish remeasured conditions from unchanged portions of the earlier map. If the boundary evidence, utilities, or off-site areas have also changed, address them in the scope instead of quietly stitching incompatible files together.
A topographic survey does not automatically verify buried utilities; see the separate guide to underground utility information on a topo survey. The main-site article on coordinating survey and engineering at the outset explains the initial handoff. This update question arises after site conditions diverge from that base.
Agree on one design base
Have the designer confirm receipt of the revised survey and retire superseded working files from the active design set. State any unmeasured areas and open assumptions on the handoff. The goal is a traceable current base for the affected decisions, not a promise that every feature on the entire site was resurveyed.
