This is a common problem on many paved trails & bikeways. It's usually caused by tree root expansion. It seems there's always money available to build new trails but little is allocated for maintenance. Some trails are so bad, I ride elsewhere.I reported to my local representatives on the condition of my bikeway to work and to fix it.
This is our remedy. Root's bumps has been painted. For caution!. I gonna make a big stink until it is level properly.