My pond is about 2-3 acres with a 14" horizontal spillway with an aluminum hood over it. I have had few issues with clogs (surprisingly) but they're always at the entrance and easy to clear. We got a bunch of rain on Sunday and I found myself waist deep clearing the entrance on Monday and today, all sticks and leaves. I don't want to find myself in this position again so I'm planning on a spillway guard. Read several posts along these lines and I think I'll go with what Theo Gallus posted in 2008, if I may quote: "Currently on my new pond, I have 5 T-posts driven into the bottom in front of the drain inlet in a semi-circle with 3 short T-posts tied horizontally across them at and above the normal water level."
Finally my question: I want to put some kind of screen in front of the T-posts and I have plenty of old cow panels laying around but the openings are 4" tall by 8" long. Do you think that is sufficient? I would think that would catch any branches which might cause a problem but allow the leaves and pine needles to go through. Tried to attach a photo; and keep in mind that the pond is high right now.
Beaver got moderately sized sticks through, but decided water lily rhizomes and pickerelweed plants were great material to clog my pipe. Learned they actually eat a lot of this stuff during the warm season. Really thinned out my water lilies before they were trapped out.