A $4 Billion project in Tarrytown, New York to replace and demolish the Tappan Zee Bridge is utilizing many aspects of the Teledyne Dredge Guidance portfolio. Five excavators outfitted with Teledyne dredging software (PDS) will be using hydraulic jack hammers to demolish underwater concrete bridge structures. The software allows them to visualize the location of their hammers relative to the structures as well as which portions have already been demolished. A clamshell wire crane outfitted with Teledyne PDS software as well as Teledyne Crane sensors will be used to clean out the debris once the excavators have broken the structures down. Finally, a small survey vessel outfitted with Teledyne PDS Multibeam software and a Teledyne BlueView SONAR provides real time “As-Building” information to the excavators and wire crane so that they have the most up to date information about the structures and debris. With the information from the SONAR, the machines can be sure that an area is fully demolished and removed before moving onto the next one. This will save time and the extra cost of having to go back to a location if something was missed.