Types of Flood Routing

Q. The point of inflection on the recession limb of a hydrograph represents

1. The cessation of rainfall
2. The condition of maximum storage in the catchment
3. The end of base flow
4. Peak runoff rate

Q. A linear reservoir is one in which

1. Storage varies linearly with time
2. Storage varies linearly with outflow rate
3. Storage varies linearly with inflow rate
4. Storage varies linearly with elevation

Q. The basic equation of flood routing through a reservoir can be modified for discrete successive intervals $\Delta t$ by which one of the following?

1. $\left[\frac{I_1+I_2}{2}\right]\Delta t+[S_1+\frac{Q_1\Delta t}{2}]=[S_2+\frac{Q_2\Delta t}{2}]$
2. $\left[\frac{I_1+I_2}{2}\right]\Delta t+[S_1-\frac{Q_1\Delta t}{2}]=[S_2+\frac{Q_2\Delta t}{2}]$
3. $\left[\frac{I_1+I_2}{2}\right]\Delta t+[S_1+\frac{Q_1\Delta t}{2}]=[S_2-\frac{Q_2\Delta t}{2}]$
4. $\left[\frac{I_1+I_2}{2}\right]\Delta t+[S_1-\frac{Q_1\Delta t}{2}]=[S_2-\frac{Q_2\Delta t}{2}]$

Q. A flood wave with a known inflow hydrograph is routed through a large reservoir. The outflow hydrograph will have

1. Attenuated peak with reduced time base
2. Attenuated peak with increased time base
3. Increased peak with increased time base
4. Increased peak with reduced time base

Q. In a linear reservoir, the

1. Volume varies linearly with elevation
2. Outflow rate varies linearly with storage
3. Storage varies linearly with time
4. Storage varies linearly with inflow rate

Q. In reservoir with an uncontrolled spillway the peak of the plotted outflow hydrograph

1. Lies outside the plotted inflow hydrograph.
2. Lies on the recession limb of the plotted inflow hydrograph.
3. Lies on the peak of the inflow hydrograph.
4. is higher than peak of the plotted inflow hydrograph.

Q. Inflow and outflow hydrograph of a channel reach are triangular in shape and plotted simultaneously as shown. The peak of inflow hydrograph is 10, 000$m^3/hr$, base time 96 hr and peak occurs 1 hr after the start, Peak of outflow hydrograph is 8000 $m^3/hr$ and occurs on the recession limb of outflow hydrograph. The value of maximum storage and time at which it occurs is :

1. 90, 000 $m^3$ and 18 hr
2. 96, 000 $m^3$ and 16 hr
3. 90, 000 $m^3$ and 20 hr
4. 96, 000 $m^3$ and 20 hr

Q. When the outflow from a storage reservoir is uncontrolled as in a freely operating spillway, the peak of outflow hydrograph occurs at

1. the point of intersection of the inflow and outflow hydrographs
2. a point, after the intersection of the inflow and outflow hydrographs
3. the tail of inflow hydrographs
4. a point, before the intersection of the inflow and outflow hydrographs

Q. Point of inflection on the recession of inflow hydrograph represents .

1. Maximum Storage
2. minimum storage
3. maximum runoff
4. minimum runoff

Q. The type of flood routing (Group I) and the equation(s) used for the purpose (Group II) are given below.
$\begin{array}{cccc}& \text{Group I}& & \text{Group II}\\ \text{P}& \text{Hydrologic flood routing}& \text{1.}& \text{Continuity equation}\\ \text{Q}& \text{Hydraulic flood routing}& \text{2.}& \text{Momentum equation}\\ & & \text{3.}& \text{Energy equation}\end{array}$
The correct match is

1. P - 1; Q - 1, 2 & 3
2. P - 1; Q - 1 & 2
3. P - 1 & 2; Q - 1
4. P - 1 & 2; Q - 1 & 2

Q. An inflow hydrograph is routed through a reservoir to produce an outflow hydrograph. The peak flow of the inflow hydrograph is $P_I$ and the time of occurrence of the peak is $t_I$. The peak flow of the outflow hydrograph is $P_O$ and the time of occurrence of the peak is $t_O$. Which one of the following statements is correct?

1. $P_I<P_O\&t_I>t_O$
2. $P_I>P_O\&t_I>t_O$
3. $P_I<P_O\&t_I<t_O$
4. $P_I>P_O\&t_I<t_O$

Q. Match List-I with List-II and select the correct answer using the codes given below the lists.
$\begin{array}{cccc}& \text{List-I}& & \text{List-II}\\ \text{A.}& \text{Evapo-transpiration}& \text{1.}& \text{Penman method}\\ \text{B.}& \text{Infiltration}& \text{2.}& \text{Snyder's method}\\ \text{C.}& \text{Synthetic unit hydrograph}& \text{3.}& \text{Muskingum method}\\ \text{D.}& \text{Channel routing}& \text{4.}& \text{Horton's method}\end{array}$

1. $\begin{array}{cccc}\text{A}& \text{B}& \text{C}& \text{D}\\ 1& 3& 4& 2\end{array}$
2. $\begin{array}{cccc}\text{A}& \text{B}& \text{C}& \text{D}\\ 1& 4& 2& 3\end{array}$
3. $\begin{array}{cccc}\text{A}& \text{B}& \text{C}& \text{D}\\ 3& 4& 1& 2\end{array}$
4. $\begin{array}{cccc}\text{A}& \text{B}& \text{C}& \text{D}\\ 4& 2& 1& 3\end{array}$

Q. Point of inflection on falling limb of hydrograph indicates

1. Peak of direct runoff
2. End of direct runoff
3. Start of direct runoff
4. Increment in direct runoff

Q. In a linear reservoir, the

1. volume varies linearly with elevation.
2. storage varies linearly with outflow rate
3. storage varies linearly with time.
4. storage varies linearly with inflow rate.