The dam is over a half mile long-
World’s biggest beaver dam discovered in northern Canada. by Michel Comte and Jacques Lemieux. Yahoo News.
Regarding beaver locally (near Pocatello, ID), today I went up to check on the big beaver ponds below Scout Mountain. I found some ATV vandal today or yesterday had ridden the ATV all over the soft mud and meadow next to the ponds, deliberately making a big mess in a vehicle closed area.