Depends on the town you are in. Here in Moultonboro, you do what you want. The guy down the street has: cut down 2 foot diameter trees on the water front to improve view, removed all natural veg and replaced with chips, put in a new sandy beach, new docks, paved his driveway, the list goes on. This past week, they tore down the lake wall, put staging in the lake and are in the process of putting a new face on the illegal slab that was poured last year. The town was informed, but nothing is done, nobody bothers to call anymore.
Permit, what is a permit ?