Flood level determination

[mize_zl]

is it possible to calculate the flood level at perticular bridge crossing the river if we just only have data for Q100 and higher tidal level but without survey level, river invert level and river width?

[drquek]

Hello Mize,

I am really glad to hear from you again.

No. But if you have a rough idea of the dimensions there is no harm in doing some trial runs using HEC-RAS.

From my experience, I am able to get pretty good estimates using survey plans or topo maps. But I must emphasize there is no substitute for the use of proper survey data.

Can you tell me what data you have, may be I can help you?

Regards,
Dr. Quek