Table 9 



Minimum and Maximum Values for Parameters Used in 



Regression Analysis of 1991 Overtopping Rates 



Parameter 



Min 



Max 



SWL, ft mlw 



10.00 



16.60 



Wave height, ft 



4.40 



12.65 



Wave period, sec 



15.90 



15.90 



Seawall freeboard, ft 



3.20 



11.30 



Beach freeboard, ft 



1.60 



10.50 



Cotan beach slope 



14.00 



19.50 



Overtopping rate, cfs/ft 



0.0000 



0.8304 



P/1 



0.4102 



0.9626 



P/2 



0.6197 



2.6915 



PI3 



0.7878 



0.9586 



PI4 



14.0000 



19.5000 



PIS 



1 .0379 



4.6730 



a 



0.0000 



0.0101 



which was expected for depth-limited breaking waves, and effects of wave 

 height were therefore reflected in PIS. 



A much simpler model provided a reasonable fit to the data and used 

 only P/1 and PI5 (beach elevation and water depth). Initial analysis of 

 the data revealed that overtopping rates for hr 30, Profile 1, at both sea- 

 wall crest elevations were exerting a very high influence on the simplified 

 regression model. Because these overtopping rates were extreme and will 

 not be found in other storms for which the regression model will be used, 

 these two values were excluded from the analysis. 



The model was: 



Q' = -0.036533 + 0.099865*/'/l - 0.062324*P/2 



-0.003554*P/5 + 0.001 1 14*^/52 



This very simple model fit the data with a correlation coefficient of 0.969 

 (R - 0.939), sum of squares of the dimensional errors was 0.0796, and 

 average difference between calculated and measured overtopping rates 

 was ± 0.047 cfs/ft. The exclusion of beach slope in this simplified model 



Chapter 3 Research Tasks A, B, and C 



35 



