Probable Maximum Precipitation

Q. What is the probable Maximum Precipitation (PMP)?

1. Projected precipitation for a 100 year return period
2. Maximum precipitation for all past recorded storms
3. Upper limit of rainfall, which is justified climatologically
4. Effective precipitable water

Q. The mean annual flood of a river is $600m^3/sec$, and the standard deviation of annual flood time series is $150m^3/sec$. The percent probability of a flood of magnitude $1000m^3/s$ occuring in the river atleast once in 5 years, will be
[Use Gumbel's method and assume the sample size to be very large]

1. 11.25%
2. 16.67%
3. 9.99%
4. 8.78%

Q. By using Gumbel's method, the flood discharge with a return period of 500 years at a particular township neighbourhood was estimated as $18000m^3/s$ with a probable error of $2000m^3/s$. What are the 95% confidence probability limits of the 500 year flood at the location?
(f(c) = 1.96 for 95% confidence probability)

1. $16100m^3/sto19900m^3/s$
2. $17050m^3/sto18950m^3/s$
3. $14080m^3/sto21920m^3/s$
4. $13600m^3/sto22400m^3/s$

Q. Match List-I (Floods) with List-II (Parameters) and select the correct answer using the codes given below the lists:
List-I
A. Standard Project Flood (SPF)
B. Maximum Probable Flood (MPF)
C. Design Flood
D. Maximum Flood
List-II
1. Includes catastrophic floods
2. Includes floods of severe conditions
3. Peak flow obtained from observed data
4. Flood of desired recurrence interval

1. A- 2, B - 1 , C - 4, D - 3
2. A- 1, B - 2 , C - 3, D - 4
3. A- 2, B - 1 , C - 3, D - 4
4. A- 1, B - 2 , C - 4, D - 3

Q. The Gumbel's reduced variate for the flood having return period of 100 years is

1. 4.6
2. 1.0
3. 2.3
4. 8.6

Q. The design flood commonly adopted in India for barrages and minor dams is

1. Probable maximum flood
2. A flood of 50-100 years return period
3. Peak flood
4. Standard project flood or a 100-year flood. whichever is higher

Q. Which one of the following is a method of extending the length of record for a frequency curve at a station?

1. Double Mass Curve Method
2. The Station Year Method
3. Thiessen method
4. Isohyetal method

Q. An annual flood series contains 100 years of flood data. For a return period of 200 years, the Gumbel's reduced variate can be taken as __________ .

1. 5.3

Q. Generally to estimate PMP, $P_n=42.16D^{0.475}$ is used (where $P_n$= maximum depth of precipitation, D = duration). What are the units of $P_n$ and D respectively in the equation?

1. mm, sec
2. cm, sec
3. mm, hr
4. cm, hr

Q. The extreme flood that is physically possible in a region from a severe-most combination, including rare combination of metrological and hydrological factors, is designated as the

1. Design flood
2. Standard project flood
3. Probable maximum flood
4. Flash flood

Q. The Standard Project Flood is

1. derived from the probable maximum precipitation in the region
2. derived from the severemost meteoro-logical conditions anywhere in the country
3. the flood with return period of 1000 years
4. the same as the probable maximum flood

Q. The standard project flood is

1. Same as the probable maximum flood
2. Same as the design flood
3. Smaller than the probable maximum flood
4. Larger than the probable maximum flood by a factor implying safety factor