(This story has been updated to include additional information)
About 2.844 million gallons of untreated sewage spilled into the Willamette River on Dec. 18 and Dec. 19.
Heavy rainfall and saturated ground conditions triggered the overflow at the 100 block of Union Street NE. It began at 6:30 p.m. on Dec. 18 and was stopped at 8:30 a.m. on Dec. 19…