Case Study: Atlantic City, NJ achieves centimeter-accurate hydrographic surveys and faster, more efficient dredging with Trimble VRS real-time positioning

Changing the Channel Advanced Technology Helps Improve a Vital Shipping Route

The U.S. Army Corps of Engineers, Philadelphia District (NAP), is responsible for maintaining the 165 km Delaware River shipping channel that serves Wilmington, Philadelphia and Camden. In 2010 the Corps began a major deepening project—raising the channel from 12 m to 13.8 m and removing roughly 12 million m3 of material—which created heavy demand for planning and pre- and post-dredging surveys across the busy waterway.

To meet that demand NAP expanded its GNSS/RTK capabilities, building a 29‑station Real‑Time Network (including 14 Trimble NetRS/NetR5 stations) controlled by Trimble VRS3Net and monitored with Trimble Integrity Manager. Combined with multibeam sonar and centimeter‑accurate RTK positioning on survey and construction vessels, the system improved survey accuracy, flexibility and efficiency immediately and for the long term, making the district the only Corps operation running its own RTN.

Atlantic City NJ

Steve Farrell

Survey Chief