CASE HISTORIES OF CORPS BREAKWATER AND JETTY STRUCTURES 

 PACIFIC OCEAN DIVISION 



PART I: INTRODUCTION 



Background 



1. The US Army Corps of Engineers (Corps) is responsible for a wide 

 variety of coastal structures located along the Atlantic and Pacific Oceans, 

 the gulf coast, the Great Lakes, the Hawaiian Islands, other islands, and in- 

 land waterways. Coastal improvements such as breakwaters or jetties are 

 necessary where a safe harbor or navigation is required. These structures are 

 subjected continuously to wave and current forces and usually are constructed 

 on top of movable-bed materials. Under these conditions structural deteriora- 

 tion can occur and, at some point, maintenance, repair, or rehabilitation is 

 required if the structure deteriorates and/or fails to serve the existing 

 needs of the project. Some of these projects have been maintained for 



150 years or more. Methods of construction and repair have varied signifi- 

 cantly during this time, principally because of a better understanding of 

 coastal processes, availability of construction materials, existing wave cli- 

 mates, regional construction practices, and economic considerations. 



Purpose 



2. The purposes of this report are to lend insight into the scope, mag- 

 nitude, and history of coastal breakwaters and jetties under Corps jurisdic- 

 tion; determine their maintenance and repair history; determine their methods 

 of construction and make this information available to Corps personnel; and to 

 address objectives of the Repair, Evaluation, Maintenance, and Rehabilitation 

 (REMR) Research Program. To accomplish these objectives, case histories of 

 Corps breakwater and jetty structures have been developed to quantify past and 

 present problem areas (if any), to take steps to rectify these problems, and 

 to evaluate remedial measures. General design guidance can be obtained from 

 those solutions that have been most successful. Information in this report 

 should be of particular value to Corps personnel in the US Army Engineer 

 Division, Pacific Ocean (POD), and its coastal districts and possibly non- 

 Corps personnel . 



