Doug Ziegler, an operator with Green Construction, of Washougal, used an excavator Thursday, to remove cottonwood trees from the Port of Camas-Washougal levee near Steamboat Landing. This week, he is working along the east end of the levee near Capt. William Clark Park. The project involves the removal of an estimated 1,800 cottonwood trees, since the trees and root systems have the potential to compromise the integrity of the levee. The project, required by the Federal Emergency Management Agency, is expected to be completed within a month. Portions of the dike trail are closed “intermittently” during the tree removal process. The trees will be shipped to a pulp mill.