Problem 10-1

Route the following triangular inflow hydrograph through a linear reservoir: peak inflow = 240 m³/s, baseflow = 0 m³/s, time-to-peak = 6 h, time base = 16 h, storage constant K = 2 h, and time interval Δt =1 h.

Problem 10-2

Solve Problem 10-1 by the storage indication method.

Problem 10-3

Determine the actual freeboard for the following dam, reservoir, and flood conditions: dam crest elevation = 125 m; emergency spillway crest elevation = 120 m; coefficient of spillway rating = 1.7; exponent of rating = 1.5; width of emergency spillway (rectangular cross section) = 18 m.
Elevation-storage relation:

Elevation (m)			120			121			122			123			124			125
Storage (hm3)			3.00			3.05			3.15			3.35			3.75			4.25

Inflow hydrograph to reservoir:

Time (h)			0			1			2			3			4			5			6			7			8			9			10			11			12			13			14			15			16			17			18			19			20			21			22			23
Inflow (m3/s)			0			15			30			45			70			100			125			150			175			165			140			125			100			80			60			50			33			25			14			9			7			5			1			0

Assume the initial reservoir pool level at spillway crest. Use program EH800.

Problem 10-4

Design the emergency spillway width (rectangular cross section) for the following dam, reservoir, and flood conditions: dam crest elevation = 483 m; emergency spillway crest elevation = 475 m; coefficient of spillway rating = 1.7; exponent of spillway rating = 1.5. Elevation-storage relation:

Elevation (m)			475			477			479			481			483
Storage (hm3)			5.1			5.3			5.6			6.4			7.6

Inflow hydrograph to reservoir:

Time (h)			0			1			2			3			4			5			6			7			8			9			10			11			12			13			14			15			16			17			18			19			20			21			22			23			24
Inflow (m3/s)			0			10			30			50			90			150			250			350			280			210			190			170			130			100			90			75			50			40			30			15			10			5			2			1			0

Assume design freeboard = 2 m and initial reservoir pool level at spillway crest. Use program EH800.