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charge resulting from the specified rainfall is determined from river 

 gagings at selected points during the flood stages of March, 1913. Ad- 

 justments are made for various rainfall and channel slopes directly as 

 the rainfall and as the one-fourth power of the slope. 



To determine the area of channel or bridge opening to carry this 

 flow, the commission suggests tentatively six feet per second as a flood 

 velocity through an improved channel, and not over eight feet per second 

 as a velocity through bridge openings. In any particular case, special 

 study of channel conditions must be made. The Indiana Flood Commis- 

 sion has thus proceeded with the compilation of recommended bridge 

 openings throughout the various parts of the State, as an approximate 

 solution of our present difficulties. A survey of actual bridge openings 

 through the State accompanies this study. 



Second Problem. 

 Design of Works. 



The second problem is to design flood protection works to take care of 

 the water which is recommended to be carried. This is not a difficult 

 problems, involving only good engineering knowledge and judgment. 



These flood improvements will consist in improvement of the chan- 

 nels of the rivers involving cleaning and straightening the river bed and 

 lengthening the bridges, and removing obstructions, and secondly the 

 building of levees to retain the flood heights. If proper surveys exist, 

 reservoir control may be studied. 



The Indiana Flood Commission has gathered together a number of 

 plans that ha^e been drawn for the Indiana cities, and it is in a postiion 

 to assist communities that desire advice on the nature of flood protection 

 works. 



Third Problem. 



Construction Work. 



After complete inforinadon has been gathered, and the best engineer- 

 ing skill has been operating, a third and most important step must be 

 taken. There must be some organization to finance and build flood pro- 

 tection works. In other words some legislative action must be taken, 

 some so-called enabling legislation. In any community some agency must 

 be created to determine the necessity of improvements, to direct their 

 construction, and to establish an assessment roll for benefits and damages 



