J R Associates

J R Associates

Utility Locating for Surveyors


Providing on-site geophysical utility locating using the latest equipment and providing turnkey CAD drawings showing the locations of the found utilities.


Utility Locating and Mapping

Utility investigations start with an existing site drawing provided by the client. The drawing can either be a professionally surveyed topo map or other to-scale drawing. Where an existing drawing is unavailable, a Google air photo can be scaled and used. We then go to the field and, following a set of standard procedures, locate and mark buried utilities. We also review existing utility drawings when available. Surveying field marks can be confusing. To aid the surveyor, we add the newly found utilities to the original drawing. The CAD drawing and the field marks are the final product of a utility investigation.


  • Major Utility Infrastructure Projects
    We have performed utility investigations at water treatment plants, gas and water pumping stations, electrical substations, power plants, and along 45 major gas and water pipeline routes.
  • Utility Investigations for Schools
    We have performed utility investigations at over 200 elementary and middle schools, high schools, and community colleges.
  • Utility Surveys at Malls
    We have performed utility investigations at over 40 shopping centers and malls throughout California.

Latest Work

Below are four examples of recent utility investigations

Fox Center West Valley College

West Valley College

We performed an utility investigation at West Valley College in support of ongoing campus renovations.
Florin Road

SMUD Electrical Improvements

This recent utility investigation was along a proposed two-mile long buried pipeline route.  
West Valley College
Field Utility Markings
CAD Drawing
Topo Drawing Showing Utilities
Florin Road
Field Utility Markings
CAD Drawing
Air Photo Showing Utilities



Gas Station

Gas Station, Fresno

This is an example of a typical gas station site where magnetics and ground penetrating radar along with standard pipe and cable locating were used to find utilities and look for unknown abandoned buried tanks.
Powell Street

Utility Investigation at an Urban Street Corner

This represents an investigation where both utility locations and depths were needed for a construction project.
Magnetic Composit Map
Magnetic Map
Radar Profile
Radar Profiles Showing Tanks
Street Markings
Air Photo with Locations and Depths
CAD Drawing
Field Markings

J R Associates Civil and Environmental Geophysics

Morgan Hill · California · 408-293-7390

jra@greatgeophysics.com