Question

1) You are considering purchasing this home adjacent to a creek. The left floodplain ara has long grass, like a pasture The main channel is a clean and straight natural channel The right floodplain has heavy brush. The bottom slope is 0.002. The 100-year flood in the creek, which is the discharge that has a 1% chance of being exceeded in any year, is 350 cfs. 500 feet downstream there is a road crossing 12 feet above the bottom of the creek and a partially clogged culvert underneath the road. During a 100-year flood, there is sheet flow over the road so the water surface elevation is 12 feet above the creek bottom. Use HEC-RAS to compute the water surface elevation 500 feet upstream from the culvert. Assume a prismatic channel and do not model the culvert. Interpolate cross sections every 50 feet. Use the default expansion (0.3) and contraction (0.1) coefficients. Place the datum at the bottom of the creek at the downstream cross section. Be careful with channel geometry. The name of the river is your last name and the name of the reach is your first name. Print and turn in the following heavy bwsh oft 45 8ft a) From the main menu>view> profile summary table 1, b) From the cross section data window plot the upstream cross section in a separate window and print c) From the main menu>view> general profile plot. Answer these questions a) What is the water surface elevation 300 and 500 feet upstream from the culvert? b) What is the water depth in the main channel 300 and 500 feet upstream from the culvert? c) What is the velocity in the left overbank, main channel, and right overbank 500 feet upstream from the culvert? d) What is the top width of the right overbank 500 feet upstream from the culvert and will the home flood?

Answer 1

Solution:-

han ne 3 52 &。 = 2f-31

← 27.2 2 . 94