Been snooping on this site for a while. Glad i found it.

Started on a new project and wanted some feedback on outlet structure size.

10-12 surface acreas of water when finished
400-450 acre drainage area

primary spillway: 8x6 concrete inlet box into a 48" pipe through the dam.

there will be a secondary spillway but woudl like to depend on primary 99% of the time.

Does anybody in this part of the country have experience with this drainage area or this size outlet.