It seems that your conveyance ...
Published by Shahram Sahraei, Hydraulic Engineer at Tehran-Boston Consulting Engineers Company
It seems that your conveyance system suffers from deposition of sediments in the concave points and therefore clogs the way of transporting water to the destination over time. If I am right, the possible solution for this issue is to consider a drain valve in the concave points of the conveyance system in order to be able to discharge deposited sediments whenever you want. Regards Shahram