(Wilsonville, OR)  --  A woman is dead, after she fell into the Willamette River and drowned.  Authorities say the woman was with her son and a friend on an old dock near the Wilsonville Sand & Gravel plant early yesterday morning, when all three tripped and fell into the water.  Officials say the after the other two were able to swim back safely, the woman struggled to get out of the water and fell back in, then began to float away, out of reach.  Police later found the woman's body between the dock and the shore.