GROTHMAN & ASSOCIATES|
A topographic survey is a three dimensional survey map showing spot elevations and/or contours, existing structures, utility locations, fence lines, waterways, etc. It is primarily used for the design of new buildings, parking areas and drainage plans.
A topographic map shows both natural and man-made features. A detailed topographic map, showing natural terrain, along with roads, existing buildings, and utilities, is necessary for good civil engineering design. Grothman & Associates prepares topographic mapping for small sites, or when elevation accuracy is critical, by field surveying.
Another method used for preparation of topographic features is global positioning systems (GPS). GPS is used at sites that are open and free of tree canopy, where an all terrain vehicle (ATV) can be freely maneuvered over the existing terrain. A GPS receiver is attached to the ATV and ground measurements are made while in the process of driving the vehicle.
For large scale mapping, 30-50 acres and above, Grothman & Associates employs an aerial photogrametry company. Grothman & Associates then performs a field survey of known or set control points visible from the air. This control is provided to the photogrametry company which then flies the site and photographs it with a special mapping camera. This photograph is then turned into a map using a stereoplotter and provided to Grothman & Associates as a computer file. The file is loaded into our Design system and the design work begins.