Answer:
There are several manmade and natural barriers that interferes with the river flow
Step-by-step explanation:
The following structures man made structures interferes with the flow of a river -
a) Gyrones
b) Canyon
c) Dams
d) diverging canals
e) Bridge abutments/pillars
f) embankments
g) spill ways
h) drainage systems
etc
Along with manmade structure several natural obstruction also interferes with the river flow -
a) Undirected mearning
b) Catchment area slope
c) slope of the river itself
d) natural barriers like valleys, hills and mountains