The New Jersey Turnpike Authority (NJTA) plans to replace the Garden State Parkway Bridge over Bass River near New Gretna, NJ. The proposed bridge replacement is in conjunction with the overall Garden State Parkway Widening Program as well as improving traffic safety.

The Robinson team provided Low-altitude Mapping Photography (LAMP) services and Photogrammetric Base Mapping at a scale of 1”=30’ with one-foot contour interval. Photogrammetric Mapping from LAMP was utilized in order to reduce the overall cost of the base mapping effort.

LAMP is a helicopter based camera system. It utilizes a Wild RC-30 precision aerial mapping camera with Forward Motion Compensation (FMC) and stabilized in the three axes using a gyroscopic mount. The combination of the slower forward speed of the helicopter and the use of FMC allows for unparalleled clarity in the photographic image. The improved image clarity allows for ground control points to be observed much more closely than with conventionally flown photography. This allows the control network to be held to a much greater accuracy. The use of LAMP allows areas that are prone to dense traffic to be accurately mapped with minimal impact on traffic flow and more safely by reducing field personnel’s exposure to hazardous situations.

RAS utilized LAMP at a nominal scale of 1”= 50’. The photography was taken at an altitude of 300 feet above the mean terrain with 60% end lap between consecutive exposures and 30% side lap between parallel flight lines.