(Portland, OR)  --  The Multnomah County Sheriff's Office is investigating a fatal boating incident that happened June 22nd in the Willamette River.  24-year-old Keileigh Seidel was riding an inflatable tube being towed by a boat when the tube collided with another boat near the Hawthorne Bridge.  Seidel was taken by one of the boats to Riverplace Marina and transported to a hospital where she died.  The results of the investigation will be turned over to the District Attorney to decide whether charges will be filed.