WEIR IS A STRUCTURE TO STORE WATER .AND WATER RAISES ABOVE
WEIR LEVEL IT OVERFLOW DUE TO GRAVTY.NO REQULATION OF
WATER IN THIS STRUCTURE.
iN BARRAGE WATER IS STORED AND REQULATED FOR IRRIGATION AND
POWER GENERATION THROUCH GATES.
weir is an impervious barrier .here water level is rise up
to the required hight & the surplus water is allowed to
flow over the weir...........but in case of barrage
adjustable gates are installed...........
WEIR: an impervious barrier which is constructed across a
river to raise the water level on the upstream side is known
as a weir. Here the water level is raised up to the required
height and the surplus water is allowed to flow over the
weir. Generally it is constructed across an inundation river.
BARRAGE: when adjustable gates are installed over a weir to
maintain the water surface at different levels at different
times is known as a barrage. The water level is adjusted by
operating the gates or shutters. The gates are placed at
different tiers and these are operated by cables from the
cabin. The gates are supported on piers at both ends. The
distance between the pier to pier is known as Bay.
Gated weir is called a barrage..Barrage works on elevated
crest and water flow is controlled using gates..
Weir is the construction where all work is done by elevated
crest.Water flow is not controlled to great extent.
Now days usually barrages are constructed because water flow
can be controlled easily.
Elevation/ht. of crest is low in barrage than weir.
if the major part of the ponding or the entire ponding of
water, ponding means to block or store water, is done by
the crest and the nil par or smaller part is done by the
shutters, such type of barrier is known as WEIR. But if the
major part of the ponding is done by gates and smaller part
by the crest, then it is called a BARRAGE OR RIVER
Weirs are typically the uncontrolled structures to raise
the water level behind it. for higher discharges water
flows over the weir.they can be about 6 to 8 m high.
Barrages are the controlled structures through gates. the
pondage area behind barrage is due to the gates and the
breast wall, if provided.The barrages are designed for
higher design flood than the weirs. barrages are now more
useful in hydro power sector.