Does anyone know of a good way to keep beavers (of the rodent variety) from boring into levees surrounding a lake? We are having a problem at our private lake of keeping them out. I don't have time to sit out there and shoot them one by one, but traps are an option if they work. Any good repair recommendations? I'm thinking about filling them back in, then laying hardened bags of sack-crete along the slopes to prevent washing.