Tree Root Sadness

Now, I have always been a lover of trees. This love affair has ended with the maples lining the back fence. I was willing to put up with them destroying the unused sidewalk back there:

But we are through, now that I have realized they are invading the bottom of the pool:

Initially, we though these lines were just wrinkles in the liner, but it has become clear that they are tree roots coming from the incriminating maples on the other side of the fence. We aren't quite sure what to do with them, as they are close to the road and likely on the town's property, but there isn't much we can do until we replace the liner (hopefully, sometime before next season). Boo.