On a Saturday in late September, several dozen individuals enthusiastically gathered with trash bags, gloves, and shovels on a mission to pick up garbage at the Sandy River Delta, the 1,500 acres of wooded trails and a grassy dog park at the confluence of the Sandy River and the Columbia River. The sprawling property, which carries the nickname “Thousand Acres,” is also home to several homeless encampments. The event was organized by Troutdale City Councilor...