Estimated long-term aggradation (+) or degradation (-) (ft/m)
The estimated long-term change in the elevation of the overbank or channel section under the bridge/culvert over the service life of the structure.
This information can usually be obtained from the output of the ABSCOUR 10 Module. Enter aggradation values as (+) and degradation values as (-).
The primary source of information regarding long-term changes in the stream channel and floodplain is typically the stream morphology report and bridge
inspection records. Refer to Chapters 11 and 14 in the Office of Structures H&H Manual for guidance on evaluating aggradation/degradation.