Marine Gulf Power


In 2018 and again in 2019, Kokosing Industrial, Durocher Marine Division, completed installing 93,368 feet of new 25kV power distribution cables for Gulf Power across the Santa Rosa Sound Intracoastal waterway between Gulf Breeze and Pensacola Beach,  Florida. 


The Gulf Power Santa Rosa crossing consisted of 4 – 10,543 ft of unarmored 25kV cable. The four cables were installed in two trenches, with two cables laid simultaneously in each trench across the Sound. The cables were installed utilizing a Cable Lay Barge towing a Hydro Jet-sled.  The jet sled had a bifricated embedment tooth, which allowed for the installation of 2 cables per crossing.  The jet sled was used from shoreline to shoreline with the cables buried 10-feet below the seafloor.  The two installations were 15ft apart.  

The Gulf Power Live Oaks crossing consisted of 4 – 12,800 ft of the same 25kV cables installed the previous year. This project was similar to the Santa Rosa project, but was more involved.  Like before, the four cables were buried in two trenches, two cables per trench, 15 ft apart.  

Due to environmental concerns, 2 – Horizontal Directional Drilling (HDD) campaigns were required: North 1,300 ft & South 600ft.  To safely install the HDD conduits, two 60 feet by 30-foot sheet pile cofferdam were installed to protect seagrass beds and an existing submarine power cable. Each HDD installation had 4 – 6” high-density polyethylene conduits installed that extended from shore to the center of the cofferdams.  During cable installation each 25kV cable was pulled through a specific conduit to the shore vault where it was terminated.  The south landing required additional shore conduits across an existing parking lot with a multitude of utilities.  It also required keeping the area open for residents to access their properties, which also added complexity to the installation.  


The State of Florida has mandated that all power distribution for the barrier islands be placed underground to protect the grid from future hurricanes. With this goal in mind, Gulf Power was building redundancy and improving the service to the island.


As a result of Kokosing’s performance during the Santa Rosa project, Kokosing was selected for the follow on Live Oaks work in 2019.

  • Project Name:
    Gulf Power