Contracted workers begin hauling debris up the steep levee bank as a Los Angeles County Sheriff patrol maintains safety. Note the use of Arundo donax, a pernicious invasive grass resembling bamboo that can grow a foot or more per day, for fencing. The U.S. Army Corps of Engineers Los Angeles District cleared 575 tons of debris from about 120 acres of riverbank, Sept. 27-Oct. 22, 2021.