Effect of Weir construction on the regime of the river: Weir is a solid obstruction which is put across a river to raise the water level.
It's very necessary to avoid any adverse effect on the environment of construction of weir on the environment, to study the fallout of.
The immediate effect of the construction of weir is an increase in water level upstream. The increase in water level is not uniform but it varies from place to place. The velocity of water also varies from place to place. The variation in flow velocity is again not uniform and hence the variation in the capacity to transport gives rise to a pattern of initial erosion and sedimentation along the river. Sedimentation over a relatively long distance occurs upstream of the intervention. Punctuated local erosion occurs an erosion advances downstream as a rarefaction wave.