The line – a joint effort between Cleco and Entergy’s Entergy Louisiana – will run from Gray to Patterson on steel structures that are designed to withstand winds of up to 150 mph, the companies said, adding that the final portions of the project are expected to be completed by fall 2018.
An Entergy spokesperson on Sept. 8 told TransmissionHub that construction on the Terrebonne to Bayou Vista line – which is entirely within Louisiana – began with right of way (ROW) clearing in mid-August.
Cleco’s portion of the project, which includes building 12 miles of the new line and additional related work, will cost about $48m, while Entergy’s portion of the project, which includes building 24 miles of the new line and additional related work, will cost about $65m, the companies said.
Cleco is building its portion of the line from its Bayou Vista substation near Patterson to a point at Bayou Boeuf near Amelia, where it will interconnect with Entergy’s line, the companies said. Entergy Louisiana is building its portion of the line from its Terrabonne substation near Gray to a point at Bayou Boeuf near Amelia, where it will interconnect with Cleco’s line, the companies said.
According to the Aug. 3 project update, work on the expansion of the Terrebonne substation began in March, and is scheduled for completion by December. Transmission line construction on acquired ROW is scheduled to be completed by April 2018, according to the project update.
The companies said in their statements that to protect wetlands, Entergy Louisiana will rely extensively on helicopters and marsh buggies to build the new line, which parallels an existing transmission line and will include erecting about 235 new structures. The steel transmission structures will typically range in height from 80 feet to 115 feet, and will be supported on one-piece steel foundations weighing as much as 20 tons, the companies noted. The largest of Entergy Louisiana’s structures will be about 195 feet tall and used in crossing Bayou Boeuf, the companies said.
“The majority of Cleco’s structures and foundations will be similar in design and size to those in the Entergy line with the exception of six structures between 198 and 239 feet tall which are required for crossing three major waterways – Atchafalaya River, Bayou Shaffer and Bayou Bouef,” Dean Sikes, Cleco’s vice president of engineering, construction and project management, said in the statement, in part.