In years past, rains like that torrent that hit Portland Thursday would have overflowed the sewer system and sent raw sewage into the Willamette and Columbia rivers.
But there was no overflow Thursday thanks to the public works project completed two years ago known as the Big Pipe. Massive tunnels channel water to a Swan Island pump station and the treatment plant in north Portland.
The Oregonian reports there had been 50 overflows a year before the Big Pipe. There have been only six in the past two years. The last one was in September when more than 3 inches of rain fell in three days.