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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. Jn 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, invyolying 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 
pians that have been drawn for the Indiana cities, and it is in a postiion 
to assist communities that desire advice en the nature of flood protection 
works. 
THIRD PROBLEM. 
Construction Work. 
After complete information kas 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 estabiish an assessment roll for benefits and damages 
