How about blocking the bottom 6" of the pipe inlet, preferably with something that would be removable if needed? The loss of a 6" tangent of cross-sectional area would be a pretty small % of the total inlet area; IF you were expecting to have a major rain event (i.e. hurricane) you could yank the 6" block out to regain maximum drain flow.

P.S. Welcome to the forum, Dr. McCoy!

Last edited by Theo Gallus; 07/26/08 01:50 PM.
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