How do heavy sediment deposits affect waterways?

Factors of importance in determining sediment impacts are the temporal variations of sediment yield. It is divided into three categories: framework bedload, matrix bedload, and suspended load.

Framework bedload  refers to the larger particles that are moved only during large flow events. It create structure of the bed.
Matrix bedload ("sediment" by fishes) refers to the part of the bed material that is small enough to be frequently entrained by low to moderate flows but is large enough to settle out of the water column in lower velocities.
Suspended load is the smallest size class of the total sediment load of a fluvial system.The deposited are usually slow-moving water, intrusion or deposition in bars and on floodplains.