Coos Bay North Jetty Repair

Proposed Coos Bay North Jetty mandatory work includes toe, side slope, and crest repair construction above -18 feet NAVD88 elevation along 2,000 feet of the jetty trunk and head. These sections will be constructed with a crest width of 30 to 40 feet, side slopes of 1V:2H to 1V:2.5V, and a crest elevation of +24.5 feet NAVD88. The estimated stone volume required for the repairs is approximately 24,430 cubic yards with minimum stone densities between 175 and 180 pounds per cubic foot. The jetty head repair includes construction of a toe berm with a crest width and height of 14 feet with side slopes of 1V:2H, and an elevation that varies with the relic stone base elevation. A jetty access ramp may be constructed on the north side of the jetty adjacent to a staging area and above the mean higher high water elevation. A temporary material off-loading facility may also be constructed in an area north of Log Spiral Bay on the east shoreline of the North Spit. Five areas totaling over 56 acres are available for material and equipment staging and storage, although no more than 20 acres can be used at any one time. Optional work includes repairs to 3,000 feet of jetty trunk and root to a crest width of 20 to 30 feet, side slopes of 1V:1.5H to 1V:2H, and crest elevations ranging from +15.5 to 25.5 feet NAVD88. The estimated stone volume for the optional repairs is 33,770 cubic yards with minimum stone densities between 167 and 175 pounds per cubic foot. Access to the north jetty is from the Trans-Pacific Highway to the North Spit roads that are single-lane, unmaintained dirt/sand roads. Portions of these roads are unlikely to support heavy construction vehicles and equipment and the transport of materials without road improvements. The access roads will be closed to the public. During construction, the contractor must maintain locked gates and provide barriers and signage to prevent public access to work areas.