PORTLAND, Ore. -- All lanes of Hwy 99E reopened Monday morning around 5:30 a.m.
Commuters had been forced to find alternate routes for days after a water main break closed northbound lanes of Hwy 99E closed near Milwaukie.
Officials with the Oregon Department of Transportation said all northbound lanes had to be kept closed until repairs could be completed.
Photos: Water main break & street damage
Kenny Pisano of the Portland Water Bureau said a 12-inch cast iron pipe burst under the center lane shortly before 4 p.m., Wednesday. Pisano said the cause of the break may never be known.
Video from the Sky-8 helicopter showed approximately 100 yards of buckled and bulging asphalt. The pipe's rupture also caused a four-foot deep hole.
According to water bureau asset engineer Peter Nierengarten, the failed pipe was just 51 years old and designed to last three times as long. Nierengarten said its failure could have come in the casting of the pipe, the thickness of its walls which were made thinner in 1959 due to rising materials costs, or the way the pipe was laid. Wednesday's warm weather didn't help.
"It's a hot day today and pressure on the main is higher than normal so any defect that might have been there was obviously exacerbated by the higher pressure, said Nierengarten.
KGW Reporters Randy Neves & Scott Burton contributed to this report