Technical Notes

Case Study: Acoustic Positioning for Connolly-Pacific's Underwater Construction Project

LinkQuest has provided the TrackLink 1500MA system along with 4 transponders to Connolly-Pacific's underwater construction project in the coastal Pacific Ocean near Newport Beach, California.  Connolly-Pacific surveyed the 1 mile long sewage pipeline owned by Orange County, California and laid tens of thousands of tons of rocks along side the pipeline to secure its positions.  It is one of the largest underwater construction project in the west coast of the United States in the year 2002.  LinkQuest's TrackLink system provided all acoustic positioning functions such as diver tracking, ROV tracking and tracking of various underwater structures during the period of more than two months.

The TrackLink 1500MA system was used in a two-day diver survey to track the positions of the pipeline accurately in June, 2002.  Combined with the result of the multi-beam echo sounder survey conducted in the previous week, Connlly-Pacific proceeded with the construction project confidently with full knowledge of the present positions of the pipeline constructed more than 20 years ago.

The TrackLink transponder was installed on the steel sled.  The steel sled was used to cover the pipeline when the rocks were thrown into the ocean from the construction barge.  Tracking the sled accurately and reliably is critical to the success of the project.  If positions obtained from the TrackLink system is wrong, the rocks may strike the sewage pipeline causing major damage and sewage spill to nearby beaches.  The TrackLink system has performed impeccably during the month long construction period and provided reliable and consistent positions of the sled and other underwater structures.

The TrackLink system was also used to track a DOE Phantom HD2+2 ROV during the construction.  This ROV was used to inspect the construction side near the construction barges.