Lily Pads taking over

Hello Group,
I live in NY on a small man-made lake(made in the 40's) that is not
more than 8 feet deep at the deepest point with an island in the
middle. Anyway, as the subject says, the Lily Pads are taking over. 30
years ago one could swim around it. 20 yrs ago we could boat aroundit
.. Now it is nearly impossible to get any boat around.(row boats)

Anyway, the back of the lake is lost I think. We want to keep them
from encroaching on the front of the lake. Aquacide was used up until
6 years ago when we stocked up with grass carp. We still row in boats
and stand in the shallows pulling up what roots we can, keeping our
swimming areas free of them, but this is alot of work.

I have heard that aerators are the solution. Comments?
Any small and productive Lily pad/root eating machines out there?
Any new technologies available?