For a windspeed of 90 miles per hour and a fetch of 14,200 feet (from 

 Fig. 1) 



gd 



-^ = 0.0185 (as previously determined) 



giving 



4= 52.2 X 14 200 ^ 26.24 

 U^ (132)2 



^- 



0.0071 . 

 From which the equivalent wave heiglit, 



0.0071 U^ 0.0071 (152)2 , n^ ^ . 



Hp = = :pr-^ ^— = 3.84 feet 



^ g 32.2 



From equation (18), the fractional growth is 

 Hp 3.84 



G,- = -£- = = 0.937 



H„^ 4.1 





The decayed wave height is then given by equation (19) as 



H^ = H^ - G^ (H^ - Hg^) = 7.8 - 0.937 (7.8 - 4.1) = 4.33 feet . 



At the end of the fetch segment, the wave height and period are approx- 

 imated by 



Hp = 4.33 feet 



T = 4.5 seconds 

 ************************************* 



VI. SUMMARY AND CONCLUSIONS 



The method presented in this report gives a first approximation for 

 estimating wave heights at the end of a fetch with a high value of bottom 

 friction (e.g., a flooded area with dense stands of grass or brush). Only 

 limited data are available for wave height growth or reduction for waves 

 passing over areas with dense bottom vegetation. The method has not been 

 verified. 



A substantial amount of data is needed for waves passing over areas 

 of flooded vegetation. The method should be verified and modified as 

 required. The shoaling coefficients (Fig. 16) and the friction factors 

 (Fig. 15) should also be compared with values from actual measurements. 



