by John A. Wott, Director Emeritus Currently there are many physical changes occurring in the north end of the Washington Park Arboretum, due to the construction of new SR-520 bridge. Local residents often remark that these changes will “disfigure” the natural landscape which has always been there. The truth is, this area has been greatly changed and altered over the past one hundred years, ever since the level of Lake Washington was lowered.