Saturday, 22 April 2017

Maintenance of Canals

Maintenance of Canals Points : chapter maintenance of canals After the construction of irrigation system in an area is completed, it becomes essential to maintain it for its proper and efficient functioning. There are various reasons due k which a canal may cease to function difficulty. These are:
1. Silting of canal
2. Branching of canal due to weak banks.
3. Weed growth
4. Over flow of canal banks

Saturday, 8 April 2017

Canal Fall - Short Questions and Answers

Canal Fall - Short Questions and Answers Points : canal fall - short questions and answers Q:1 Write the basic requirement of canal fall. Ans: (1) suitable energy dissipation arrangement. (2) Fluming (3) crest level (4) low cost Q:2 Write down the classification of falls. Ans: Falls may be divided into four principal classes with reference to the approach conditions
(1) Falls designed to maintain the depth discharge relation
(2) Falls designed to maintain a fixed supply level in the cannaI above the work (3) Falls designed to admit the variations of the surface level above the work at the will of the operator
(4) Miscellaneous Types

Canal Fall

Canal Fall Points : Canal Fall Fall is an irrigation structure constructed across a canal to lower down its water level and destroy the surplus energy liberated from the falling water which may otherwise scour the bed and banks of the canal.

We have seen in chapter 14 that the canal requires a certain slope. Depending upon the discharge, to overcome the frictional losses. This slope may vary from 1 in 40000 for a discharge of about 1.5 cumecs to about 1 in 8000 for a discharge of 3000 cumecs. This slope is, therefore, quite flat in comparison to the available ground slope of in average value of 5 to 20 cm per kilometre length.

1. (in 200 to 1 in’50). Thus the ground slope in nature is always very much steeper than the design bed slope of irrigation canal, based on the silt theories. If an irrigation canal, taking off from its head, is in cutting, it will soon meet with condition when it will be entirely in embankment.

Saturday, 4 February 2017

Distribution Works

Distribution Works Points : distribution works, essential requirement of out let, types outlet, non-modular outlet, rigid module, non modular outlets pipe outlet, semi-module or flexible outlets, kennedy’s gauge outlet Outlets An outlet is a small structure which admits water from the distributing channel to a water course of field channel. Thus, an outlet 13 a sort of head regulator for the field channel delivering water to the irrigation fields. The responsibility of maintenance of the distributing channel and the whole canal network lies with Government, while that of the field channels lies with the farmer. The outlet is the connecting medium for the two. Essential requirement of out let Since the efficiency of a canal network mostly depends upon functioning of the out lets and other regulation works, a canal outlet should fulfill the following requirements.

1. The outlet should be strong, with no moving parts liable to be damaged or requiring periodic attention and maintenance.
2, It should be so designed that the farmer cannot temper with its functioning and any interference from him should be easily detectable.
3. Since a large number of out4ets are fixed. on a distributing channel, the moat essential requirement is that it should e cheap.
4. The design should be simple so that It can be constructed or fabricated by local masons or technicians,

Monday, 23 January 2017

Cross Drainage Works – Short Question and Answers

Cross Drainage Works – Short Question and Answers Points : cross drainage works –short question and answers Q.1: Define the term cross drainage works. Ans : Cross drainage work to a structure carrying the discharge of a natural stream across canal intercepting the stream. Q.2: Write down the name of different types of cross drainage works carrying can over the drainage. Ans : Depending upon the relative levels and discharges, cross-drainage works may be of the following types:
In this type of C.D. work, the canal is carried over the natural drain. The advantage of such arrangement is that the canal, running perennially, is above the ground and is open to inspection.

Cross Drainage Works

Cross Drainage Works Points : cross drainage works, types of cross drainage works, cd work carrying canal over the drainage, cd work carrying drainage over the canal, cd work admitting the drainage water into the canal, canal escape Cross drainage work is a structure carrying the discharge of a natural stream across a canal intercepting the stream. When a canal is to be taken to the watershed, it crosses a number of natural streams in the distance between the reservoir to the watershed. Once the canal is taken to the watershed, no cross-drainage works are normally necessary except when the canal leaves the watershed for some distance forming a loop. However, when the canal is aligned as a contour canal, a number of cross-drainage works are necessary.

A cross-drainage work Is generally a very costly item, and should be avoided as far as possible by (i) diverting one stream into another, or (ii) changing the alignment of the canal so that it crosses below the junction of two streams.

Friday, 20 January 2017

Canal Regulation Work - Short Questions and Answers

Canal Regulation Work - Short Questions and Answers Points : canal regulation work - short questions and answers Q.1: Define the regulation work of canals. Ans: Any structure constructed to regulate the discharge, full supply level or velocity in a canal is known as a regulation work. Q.2: Write down the name of various regulation works. Ans: The various regulation works may be categorized as under:
1. Canal fall
2. Head regulator or head sluice.
3. Cross regulator.
4. Canal escape.
5. Canal outlet