TYPES OF INTAKES
Depending on the source of water the intake works are classified as follows.
i. Lake intake
ii. River intake
iii. Reservoir intake
iv. Canal intake
For obtaining water from lakes mostly submersible intakes are used. These intakes are constructed in the bed of the lake below the low water level so as to draw water in dry seasons also. It consists of a pipe laid in the bed of the river, one end of which is provided with bell mouth opening with fine screens. The water enters through the bell mouth opening and flows under gravity.
I. No obstruction to navigation
II. No danger from floating bodies
III. No trouble due to ice.
It is a circular masonry tower of 4 to 7 meter in diameter constructed along the bank of the river at such place from where required quantity of water can be obtained even in the dry period. The water enters in the lower portion of the intake known as sump well from penstocks the penstocks are fitted with screens to check the entry of floating solids and are placed on the downstream side so that water free from most of the suspended solids may only enter the lack well. Number of pen stock openings is provided in the intake tower to admit water at different levels. The opening and closing of penstock values is done with the help of wheals provided at the pump-house floor.
It is mostly used to draw the water from earthen dam reservoir. It consists of an intake tower constructed on the slope of the dam at such place from where intake can draw sufficient quantity of water even in the driest period. Intake pipes are fixed at different levels so as to draw water near the surface in all variations of water level. These all inlet pipes are connected to one vertical pipe Indies the intake well screens are provided at the mouth of all intake pipes to prevent the entrance of floating and suspended matter in them. The water which enters the vertical pipe is taken to the other side of the dam by means of an outlet pipe. At the top of the intake tower sluice values are provided to control the flow of water. The value tower is connected to the top of the dam by means of a foot bridge gangway for reaching it.
Canal intake is a very simple structure constructed on the bank. It consists of a pipe placed in a brick masonry chamber constructed partly in the canal bank on one side of the chamber an opening is provided with coarse screen for the entrance of water. The end of the pipe inside chamber is provided with a bell mouth fitted with a hemispherical fine screen. The outlet pipe caries the water to the other side of the canal bank
From where it is taken to the treatment plants one sluice value is operated by a wheel from the top of the masonry chamber provided to control the flow of water in the pipe.
Copyright © 2018-2021 BrainKart.com; All Rights Reserved. (BS) Developed by Therithal info, Chennai.