Here's the website with all of the details for the project.
The Morrison-Yamhill MAX Improvements will rejuvenate track in one of the oldest sections of the MAX system. But pedestrians, bicyclists and auto drivers will benefit, too, as the project will improve the surface of a busy one-block stretch on SW 11th Avenue in downtown Portland. Before that long-term gain, travelers will need to make some temporary adjustments beginning April 30 as the construction will lead to MAX and Portland Streetcar service disruptions as well as road and sidewalk closures. Also, MAX riders may want to think twice before buying a month pass for May as the improvement project will impact service on all lines from Sunday, April 30 through Saturday, May 20.
During the Morrison-Yamhill MAX Improvements project, TriMet will upgrade the track on SW Morrison and Yamhill streets at 11th Avenue, removing wooden ties and replacing special track work as well as installing new switch machines and cables for the signal system. This will help keep the MAX system moving and create a smoother ride on board both trains and streetcars. It also will benefit pedestrians, bicyclists and drivers as potholes and broken bricks will be repaired. This area is heavily used by MAX trains, streetcars, autos, cyclists and pedestrians. Further east, crews will be replacing curved rails on Morrison and Yamhill that connect to 1st Avenue.
MAX Blue, Green and Red lines will be disrupted and all MAX lines will have reduced service from Sunday, April 30 through Saturday, May 20. Space on board trains will be very limited, riders should consider altering trips to avoid main commuting hours, using TriMet regular bus service, carpooling, biking, walking, working from home or using other transportation options. Those who buy monthly passes may want to consider getting a book of tickets for May instead. May passes go on sale April 20. Riders can get line-by-line details, view animated maps of the service changes and check the special schedules that will be in effect during the project at trimet.org/morrisonyamhill.
All Portland Streetcar lines will be disrupted for the first two weeks of the project, from Sunday, April 30 through Saturday, May 13. Riders can get service information at portlandstreetcar.org/service-interruption-april-30-may-13.
The construction will close some streets, sidewalks and crosswalks in downtown Portland. Also shuttle buses will be running on several streets, to provide alternate service for MAX and Portland Streetcar.