Soon Trout Creek, Gordon Creek, and Buck Creek all enter from the right as the river winds through Oxbow Regional Park between and from the mouth. Passing Camp Collins about later, the river receives Big Creek from the right. Dabney State Recreation Area is on the right about later. Lewis and Clark State Recreation Site is on the right and Troutdale on the left at about from the mouth, where Beaver Creek enters from the left. Shortly thereafter, the river passes under Interstate 84 and flows by Portland-Troutdale Airport, which is on the left about from the mouth. The Sandy River then joins the Columbia River about from where the larger river enters the Pacific Ocean. The confluence is about east of Portland, near the lower end of the Columbia River Gorge.