4 Way Sweep

Northwestern Surveying and Engineering, Inc. conducts underground utility locating and mapping (4-way sweeps) – an investigative geophysical survey which is done with the use of electronic pipe locators (radio detection) which are used to locate, trace and map underground features. During this survey, above ground utilities are also located and shown on the overall sweep map.  This type of survey is usually used for damage prevention, safety while excavating, or new route planning. Our personnel have over of fifteen years of locating experience with an impeccable safety record, so you can be sure that your site has been properly marked before you begin working.

Our crews are able to work in all types of environments: in-stream, roadway, pipeline mainline, pumping stations, and electrical sub stations.  Survey crews use a combination of calibrated radio detection equipment (RD7000) and survey grade GPS which ensures the greatest accuracies possible. The final deliverable is a survey map (sweep map) which shows the located underground utilities as well as the aboveground utilities, buildings, fences, and other existing structures.

All crews are operated qualified and certified through a rigorous classroom training and field apprenticeship program.  Crews must demonstrate competency before they are even allowed to perform these types of surveys due to the risk poor performance poses to safety.