Faulty deck panels are causing a shut down of the Morrison Bridge Sunday.  If that is your main way across the Willamette River, you will need to find another way.  Here is a press release with full details from Multnomah County:

The Morrison Bridge will be closed to motor vehicle and sidewalk traffic on Sunday, March 23 from 7 a.m. until as late as 7 p.m. to set up a temporary traffic control change on the lift span deck.  The change is related to an investigation of the condition of lift span deck panels that were installed in 2011 – 2012.
During the closure, on and off-ramps from the bridge to I-5 and I-84 will be closed.  While the I-5 southbound City Center/Morrison Bridge off-ramp (exit 300) will be closed, the I-5 southbound ramp to Highway 99E/U.S. 26 will remain open. Motorists can access I-5 north at N.E. Broadway and N. Williams Avenue and enter I-84 eastbound at N.E. Grand Avenue and N.E. Everett Street.  Onramps to the bridge will be closed at S.E. Grand Avenue and S.E. Martin Luther King Jr. Blvd.
Alternate downtown river crossings include the Hawthorne and Burnside bridges.  During the bridge closure, TriMet’s 15-Belmont line will use the Burnside Bridge in both directions.  River traffic will not be impacted by the closure.
Traffic Configuration Changes
During the closure crews will change the traffic configuration on the lift span for the next phase of the investigation.  When the bridge reopens Sunday evening,  two westbound lanes on the north side of the lift span will be closed and the outside eastbound lane (which has been closed the past month) will reopen. 
For the next phase of the investigation there will be two lanes open in each direction on the lift span, instead of the normal three lanes.  All ramps will remain open, but lanes will be shifted around the work area.  This configuration is expected to remain in place for two months.  The investigation requires the removal and detailed inspection of some of the decking material in the four quadrants of the lift span area on the bridge.