Irrigation and Drainage Engineering

Question 1

The maximum permissible water velocity for clay loam canal surface based on PAES 603:2016.

Answer 1

0.80 m/s

Question 2

Application of water in the soil to supply moisture needed for plant growth.

Answer 2

Irrigation

Question 3

The minimum permissible velocity for water with sediments in lined canals based on PAES 603:2016.

Answer 3

0.9 m/s

Question 4

Loss of water from a channel during transport due to seepage and percolation.

Answer 4

Conveyance loss

Question 5

Depth of water flow where the energy content is at minimum hence, no other backwater forces are involved.

Answer 5

Critical depth

Question 6

Ratio of the actual crop evapotranspiration to its potential evapotranspiration.

Answer 6

Crop coefficient

Question 7

Moisture content of the soil when gravitational water has been removed.

Answer 7

Field capacity

Question 8

Elevation of water surface in a stream with reference to a certain datum.

Answer 8

Stage

Question 8

Number of days between irrigation applications.

Answer 8

Irrigation interval

Question 8

Removal of excess water.

Answer 8

Drainage

Question 9

Surveying instrument used for determining land areas in a topographic maps.

Answer 9

Planimeter

Question 9

Elevated section of open channel used for crossing natural depressions.

Answer 9

Flume

Question 10

Facility for determining water consumptive use of crops in an open field.

Answer 10

Lysimeter

Question 11

Time required to cover an area with one application of water.

Answer 11

Irrigation period

Question 12

At optimal emitter spacing, drip emitter spacing is ___ of the wetted diameter estimated from field tests.

Answer 12

80%

Question 13

Reference crop evapotranspiration is the rate of evapotranspiration from a reference surface which is a hypothetical reference crop with an assumed crop height of 0.2 m and an albedo of _______ (AMTEC, 2020).

Answer 13

0.23

Question 14

Manufacturer’s coefficient of variation is the measure of the variability of discharge of a random sample of a given make, model and size of emitter, as provided by the manufacturer and before any field operations or aging has taken place determined through a discharge test of a sample of 50 emitters under a set pressure at ___ ºC.

Question 15

Which one is the flattest canal side slope?

Answer 15

4:1

Question 16

Determine the side slope angle Ө with the horizontal plane of an unlined canal with side slope ratio (run: rise) z of 2:1.

Answer 16

tan Ө = rise /run
Ө = arctan (rise /run)
= arctan (1/2)
= 26.6º