Laserfiche WebLink
<br />STEP 10 (continue.!!), <br /> <br />MErmOD 2 " COMPUTER ASSISTED HYDRAULIC ANALYSIS <br />(Manning's Equ::ltion) <br /> <br />There are a numher of PC p['ograms available fOI" performing hydraulic analyses <br />using Manning's ][quation. Once you have acquired sueh a program, follow these <br />steps: <br /> <br />Look at the cross-section and select polinlts on the cross-section to enter <br />into the computer <br /> <br />For each pcint on the cross-section entl~r x and y co-ordinates <br /> <br />From Table of Hydraulic Roughm~:ss Conditions determine <br />Manning's n Values and enter them into the computer <br /> <br />Calculate Channel Slope in three steps: <br /> <br />1) Measure the distance along the length <br />between the cross-sections <br />2) Calculate the difference in chanael bottom <br />elevation bl:tween the cross-sections <br />3) Divide the elevation difference by the <br />channel distance to arrive at the slope <br /> <br />Enter into the computer a water depth of 1 foot <br /> <br />Enter into the computer a water depth of 2 feet <br /> <br />The program will compute flow and nlocity <br /> <br />Compare flow for depth of 1 foot ane 2 feet to flow determined <br />by Hydrologic Analysis <br /> <br />Make adju:;tments in dl~pth to adjust :Ilow <br /> <br />Once the flow calculated by the competer matches the flow from <br />the Hydrologic Analysis, you have the flood depth <br />