ENVIRONMENT: GFA completes major project for Core of Engineers

TRAVERSE CITY – Airborne Global Positioning System (GPS) technology and ideal spring weather enabled Gourdie/Fraser & Associates (GFA) to complete aerial photography and associated land surveying of 180 miles of Ohio Riverfront in two weeks–less than one-fourth the time such a project would typically take.

The survey information will be used by the U.S. Corps of Engineers to create new navigational maps of the Ohio River. The Huntington, WV, district of the Corps of Engineers contracted with GFA, after the Detroit district recommended the firm.

According to Professional Surveyor Garth Stowe, GFA’s supervisor of field operations and project manager for the Ohio River project, three environmental conditions had to be in place for two days to get the right aerial photographs.

“First, the photos had to be taken before leaves began to bud on the trees so that the view of the river was not obstructed,” he said. “Second, the skies had to be clear. Finally, the river level had to be at a certain height.”

The team had about a seven-day window to meet those conditions.

Airborne GPS uses a receiver to derive an exact location from satellites. To conduct an aerial photography survey project, an airplane equipped with a GPS receiver flies over the site taking multiple photos.

At the same time, surveyors on the ground collect data with their own GPS receivers. A computer then processes the air and ground coordinates to determine the location of the photographs.

“It was a huge project, encompassing approximately 1,000 square miles in area and there were thousands of photographs taken,” said Stowe. “But with aero triangulation, cartographers will be able to determine the precise location of each photo.”

While Gourdie/Fraser was the prime contractor of the job, it subcontracted the aerial photography to Western Air Maps in Kansas City. Mike Rademaker, Senior GPS Technician, was the project field supervisor and coordinated all field operations.

Gourdie/Fraser has held the surveying contract with the Detroit district of the Corps of Engineers for 20 of the past 25 years. The contract, open to any firm in the nation, is renewed every three years. Competing firms go through a rigorous qualification and selection process.

“When our northern Michigan firm with 50 staff members competes successfully for the contract against nation wide firms with 300 to 500 staff members, it is an indication of the quality of work that we do,” Stowe said. “The Ohio River project is evidence of that.”

The Corps of Engineers is a department of the U.S. Army, responsible for maintaining shipping channels, harbors, piers and breakwaters for both recreational and commercial boating. The Detroit district encompasses the Great Lakes Basin and is one of the largest districts of the Corps.

Since 1948, Gourdie/Fraser has been involved in many public and private projects, including highway projects for MDOT, Grand Traverse Resort, Sugar Loaf Resort, NMC, the extremely low frequency (ELF) Polaris defense communication system in the UP, and residential developments. BIZNEWS