ST. MARYS, W.Va.-- Construction is under way on a $276 million hydroelectric plant at the Willow Island Locks and Dam.

State and local officials joined American Municipal Power representatives at a groundbreaking ceremony Thursday.

The 35-megawatt plant is expected to create 400 construction jobs. When it's completed, it will have about nine full-time employees.

U.S. Army Corps of Engineers Lt. Col. Andy Ford said the plant is expected to begin operations in 2015.

Acting Gov. Earl Ray Tomblin said the hydroelectric plant will help diversify West Virginia's energy portfolio.