You should probably install some sort of brush guard on the intake side of the culvert, to prevent blockage in the event of a heavy rain.
I should have heeded my own advice. Here is a picture of a culvert on my driveway, after a recent rain. Due to the blockage, the water rose high enough to overflow the drive at another spot, and cause minor erosion.
Could've been worse. Now, I have to engineer some sort of brush guard.
