I have an Agri Drain bar guard on my spillway pipe...
This spring it has been getting clogged up with floating vegetation. Does anyone know of a different guard that keeps debris away from the pipe but still allows water to flow out?
Rob, someone here posted photos awhile back showing a really good cage type concept they built around their spillway, although if I remember correctly, it was a horizontal spillway as opposed to a vertical spillway, which I'm assuming you've got. In any event, the cage extended for probably 3 - 4 feet around the spillway entrance, allowing for plenty of clear space around the spillway while protecting it from debris. I think they also had an actual cover on the spillway itself to guard against fish getting out, but the big cage prevented larger materials from getting through. I don't know if that would be practical for your application, but perhaps you could look at the idea of a larger cage and even tack some steel mesh around it to prevent the weeds from getting through, creating a clear zone around your main spillway pipe. Just a totally amateur thought.
Bingo! That's the one I was thinking about!
Here is one of ours. Works well but most water goes out the small pipe (on left of pipe) or the seperate open siphon and not over the top except in big rain events ( 1 or 2 times a year).
It's a vertical pipe. I was looking around and maybe something like this would work.
It would fit over my existing pipe and the water could flow from under this while the vegetation floating above.
or this....
This is what I was envisioning. It's kind of like Brettski's great cage, but just turned up for a vertical pipe. It could probably clog with weeds, though, and then you'd be back where you are now. The first cover might work for the very reason you stated - water could still flow beneath the surface where the weeds were less prevalent even if the top had collected a bunch of junk.
Just make sure that it can't be stopped up.