Abstract:
The assessment of sediment transport capacity of the channels is an important aspect and needs careful attention at the time of designing/planning a new canal project for maintaining its water carrying capacity during its life time. Two types of measures are normally adopted to get clear water from the barrage/weir which are as below:
1. Preventive measure which is applied just upstream of the head regulator to reduce the entry of sediment to the channel.
2. Curative measure which is applied just downstream of the head regulator to eliminate the problematic coarser fraction of sediment.
With the help of these measures, coarser fraction of the sediment responsible for the silting of the channels is reduced.
It has been observed that these measures are effective only within some specific conditions. Whenever the field conditions are different, the coarser sediment concentration increases in the channels creates the problem of silting due to which the flow carrying capacity of the channels reduces leading to the reduction in CCA of the canal.
For minimising these effects, it is essential that model studies be conducted for the entire canal system at the planning stage itself. Physical modelling of the entire canal system is not feasible due to modelling constraints as well as due to heavy financial requirements and long span of time involvements.
In view of the above constraints it is apparent that mathematical/numerical modelling techniques be used to study the changes in bed profile of the canal system due to silting occurring during operation of canals.
With the above object in mind, a numerical modelling of an existing Sarda Feeder Channel system has been carried out using HEC-6 software for studying the extent of silting and its profile in the entire length of Sarda Feeder Channel.
