For such a recursive type calculation, computer computations reduce 

 the effort required. However, since this is a one-dimensional formulation 

 of the problem, it is possible to carry out the necessary computations 

 manually. 



The March 1955 storm on Lake Erie is used to demonstrate the scheme. 

 A plan view of Lake Erie is shown in Figure 3-59. The width and cross- 

 section area of the Lake are shown in Figure 3-60, mean bottom profile in 

 Figure 3-61, and wind and wind direction data for the March 1955 storm in 

 Figure 3-62. 



In the following example problem computations are made at a single 

 spatial point where Q is evaluated at a distance of 3Ax from Buffalo 

 (Fig. 3-59) at a time when the wind speeds are approximately maximum. 

 Tables similar to Table 3-10 should be used in manual calculations. 



*********** EXAMPLE PROBLEM 



GIVEN: 



The wind at the new time level is 50.5 miles per hour and 9=4.0. 



The corresponding water surface widths for this section are h-i+i/z = 26.3 



miles and hi+3/2 =21.0 miles, 

 the previous time level are 



The values from preceding calculations at 



Also required is the value of Q. from the previous spatial step which 

 is given as +0.0915 mi?/hr. 



3-134 



