Kaumalapau Deep Draft Harbor (DDH) is located on the southwestern coast of Lanai and is the main commercial seaport for the island of Lanai.  The Kaumalapau Harbor was authorized under the Energy and Water Development Appropriations Act of 2001 (Public Law (PL) 106-377), and 2002 (PL 107-66) and 2004 (PL 108-37).  The project is in the operation and maintenance phase.  The local sponsor is the State of Hawaii Department of Transportation Harbors Division.  

Kaumalapau DDH was originally built in the 1920’s by James Dole, founder of the Hawaiian Pineapple Company.  The harbor was officially transferred from the Lanai Company to the State of Hawaii Department of Transportation Harbors Division in July 2000.  Repeated storm events between the 1980’s and 1990’s created significant damage to the breakwater. 

The U.S. Army Corps of Engineers (Corps) repaired the existing breakwater at Kaumalapau DDH for a total project cost of $28,200,000 (Federal:  $22,600,000; non-Federal:  $5,600,000). Construction was initiated in February 2006 and completed in June 2007 by Traylor Brothers, Inc. The completed breakwater is 320 feet long with a crest elevation of +14.5 feet above mean lower low water.  Construction included the placement of 819 core-loc units (weighing 35 tons each) that constituted a unique engineering and construction challenge. Under a separate contract, a new rock wall and project sign was awarded. in September 2008 in the amount of $160,340.  The completion of the wall and plaque was accepted on 23 January 2009 by RMA Land Construction, Inc.

The Corps is responsible for maintaining project depths and the structure.