APPENDIX C: COMPUTER PROGRAM BWL0SS2 

 Estimation of Economic Losses from Transmitted Waves 



Program purpose 



1. BWL0SS2 fits an Extremal Type I long-term probability distribution 

 to transmitted wave height data and estimates expected annual economic losses 

 due to wave attack after a protective breakwater has been built. 



Program capabilities 



2. Estimation of incremental economic benefits directly related to a 

 rubble-mound breakwater built for wave protection requires that the costs to 

 the beneficiaries with the breakwater in place be determined. A rubble-mound 

 breakwater built so high that no waves are transmitted during the worst con- 

 ceivable conditions is seldom affordable. It is often more cost effective to 

 accept a small amount of risk that waves from a very severe storm will be 

 transmitted and cause an estimable degree of economic loss. The damage caused 

 by these transmitted waves is assumed to follow a previously derived economic 

 loss function of wave height. 



$L(H ) = $L 

 3 max 



A(H -H, )' 

 s Lo 

 e 



(CI) 



where 



$L(H ) = the economic losses caused by a storm of significant wave 

 height Hg 



$L_„„ = the maximum conceivable loss due to wave attack 



Hr = the maximum wave height for which losses can be neglected 



A = a coefficient determined by regression of historical Hg , 

 $L(H ) information 



The computer program BWL0SS1 (Appendix A) is available to derive this economic 

 loss function from property valuations, coastal engineering data on wave cli- 

 mate, and historical economic loss data. The program BWL0SS2 requires that 



^^max ' ^Lo , and A be input, along with the e and ij) parameters of the 

 Extremal Type I cumulative probability distribution of significant wave 

 heights H which defines the wave climate incident on the seaward side of 

 the breakwater as follows: 



CI 



