PREFACE 



This report describes a method for estimating the flow rate through the gaps 

 of offshore segmented breakwaters caused by wave overtopping. Factors that can 

 be investigated using this method are the influence of breakwater freeboard, 

 wave height and period, breakwater length and spacing, number of breakwaters, 

 distance offshore, water depth at the breakwater, and shore attachment on the 

 flow rate. Other wave effects on hydraulics, such as diffraction, refraction, 

 reflection, and wave-current interactions, have not been considered. The work 

 was carried out under the offshore breakwaters for shore stabilization and 

 evaluation of shore protection structures programs of the U.S. Army Coastal 

 Engineering Research Center (CERC). 



The report was prepared by William N. Seelig and Dr. Todd L. Walton, Jr., 

 Hydraulic Engineers, under the general supervision of Dr. R.M. Sorensen, Chief, 

 Coastal Processes and Structures Branch and Dr. J.R. Weggel, Chief, Evaluation 

 Branch. 



Comments on this publication are invited. 



Approved for publication in accordance with Public Law 166, 79th Congress, 

 approved 31 July 1945, as supplemented by Public Law 172, 88th Congress, 

 approved 7 November 1963. 



CED E. BISHOP 



Colonel, Corps of Engineers 



Commander and Director 



