On Wednesday, I had the opportunity to tour the construction site around the west abutment of the Portland-Milwaukie Light Rail Bridge through the Oregon section of the Institute of Transportation Engineers.
At present, most of the work is centered around the construction of the in-water piers and the two towers that rise from each. The western structure is nearly at full height presently, with the towers rising 160 feet from the pier as seen below (the eastern structure is much smaller at the moment). They’ll be 180 feet when complete.
On the top of the right tower, you can see a saddle structure that was recently installed. The saddles are the parts through which the cables are threaded, and for the bridge to be structurally sound, they must be precisely located with a tolerance of fractions of an inch. To accomplish this, the saddles are placed into steel and re-bar skeletons by “specialists” on the ground and then lifted into place on the tower where the concrete is poured.
In order to ensure sensitivity to the river’s ecosystem, in-water construction can only take place between July 1 and October 31 each year. So the first structures built last summer were the cofferdams at the base of each tower. I snapped a photo of the underside of the western cofferdam below. The eastern cofferdam is pretty easy to observe from the Eastbank Esplanade. Those views will become much more dramatic as the towers grow.
Once the towers are complete, the deck itself will be constructed using the “balanced cantilever” method. The deck will grow outward from each tower structure, always with an equal amount of deck existing on each side of the towers. The cables will be threaded through the deck and towers as the deck grows. The last pieces of the construction will be connecting the two sections of deck in the middle, and then connecting each section to its abutment. The photo below is of the western abutment.
I snapped this photo from what will eventually become the South Waterfront Greenway, a strip of park with dedicated paths for bicycles and pedestrians. The land around the bridge will see the development of many tall, mixed use buildings like those recently constructed along the south waterfront. The Greenway will, I think, be among the best walks or rides in Portland when our beautiful cable-stayed bridge is finished and the structures begin to rise from its base.
22 responses to “Checking In on the PMLR Bridge”
“Milwaukie”.
As a childhood citizen of Clackamas County, it is my life-long solemn duty to point out this common spelling error whenever and wherever it happens. :-)
(Also, too, a Portland-Milwaukee light rail line would be considerably longer and more expensive to construct and operate than a Portland-Milwaukie, line, unless you use another Portland.)
Portland-Milwaukee line
“Minot, North Dakota. Doors open on my right. Next station, Grand Forks…”
Extremely cool!
The rebar cage with saddles Brian shows in his second photo is already atop the northern spire of the western tower.
There will not be a cross brace between the two spires at their tops. Does that mean the bridge has four towers?
I sat in on Vera Katz’s planning committee for this structure. Vera and Rob Barnard, TriMet’s chief effectuator for the bridge component of PMLR, deserve tremendous credit for guiding us through a difficult and tortuous process that will result in a highly functional and spectacularly beautiful bridge.
Bob- Fixed, thanks for pointing this out! I swear I had that right, so I’m going to go ahead and blame auto-correct, however true that may or may not be. :)
Jim- Good question about the towers. they’re connected at the bottom by the in-water pier and definitely not at the tops. I wonder if there might eventually be some connection between the two just below the deck? I agree that it will be a fantastic bridge, both aesthetically and functionally.
Portland-Milwaukee line
No sense in a light rail line between the two, there’s already heavy rail (but I’m sure most here already know that):
http://www.amtrak.com/empire-builder-train
;)
I was in favor of this bridge (as a ‘BRT’ for #9, 17 & 19 lines), although opposed to Milwaukie LRT.
I wonder if Trimet will be able to run buses over the bridge before the LRT is completely finished. This is to avoid possible traffic jam-ups on and around the Ross Island bridge.
I’d move bus lines to the new bridge ASAP, if nothing else to give poor Streetcar something to connect to.
And it would be nice if someone gave the bridge a name… I’m assuming TriMet gets to pick, and will have a public process for doing so.
My advice: Please don’t name it after some bureaucrat–I find it slightly obnoxious that we have public works named after fellows such as Washington County commissioner Roy Rogers, former OTC chair Glenn Jackson, or former TriMet director William Robertson (who died in 1997 during Westside construction, and thus had the MAX tunnel named after him). The case of Roy Rogers Road is a particularly obnoxious bit of vainglory (mitigated only by the fact that many think the road is named instead after the cowboy), as Commissioner Roberts is still very much alive; the other two examples at least were done posthumously.
OTOH, if they were to call it the Fred Hansen bridge, I can think of at least a few heads who would spin right off…. :)
I love this bridge! It will be great to have a cable-stay bridge over the Willamette to go with all the other types of bridges we have. It will also create a great way for cyclists to access the springwater trail and do wonders for transit. I hope the busway is completed as soon as possible so all the people who ride the 9, 17, and 19 can benefit from avoiding the Ross Island Bridge. I keep trying to think of any other bus lines that could use it. The 4 could use the new bridge if we built an overpass or underpass from Division to avoid the UP tracks. Any thoughts on whether that would be worth the cost? I also think 11th/12th needs grade separation at the tracks.
An overpass across the UPR tracks would be beneficial for many reasons besides bus traffic.
For those interested on the various reworks in the area, see http://trimet.org/pdfs/pm/stations/Station-Area-Fact-Sheets/PMLR_Clinton_Fact_Sheet_September2012.pdf.
One downside is that the current pedestrian bridge at SE Brooklyn is being demolished (it blocks the planned MLR right-of-way), and the planned replacement bridge, to be located at SE 14th, was one item that was removed from the project to make up for the reduced federal match.
I have said so here already, but this fabulous piece of transit infrastructure ought to be named for Ray Polani, whose lifetime of advocacy for transit began with CIAT–“Citizens for Immediate Adoption of Trollybuses” back in the 1970s.
Sorry, Ray, that we got streetcars before trollybuses, but there still is hope that we can measure up to Seattle and Vancouver.
For a bit more on Ray and his work, see this old PT article from 2006.
A bit off-topic, but maybe someone can confirm or deny that Ray Polani and his crew have opposed many (most?) of the rail transit projects of the last few decades. I remember their opposition to the West Side and Interstate projects, but am fuzzy on their stance on the Airport and 205 extensions.
It seemed at the time that they stood for the perfect over the good, holding that the the light rail projects as developed incorporated unacceptable compromises. Jus’ wonderin’ . . .
Back to the actual topic of the post – thanx Portland Transport for a bit of unabashed gee-whizzery. A pleasant contrast to the bitter innuendo that passes for coverage in the ‘Gonian!
RAY POLANI
I couldn’t care less about this bridge, part of a project that is a colossal waste of money as far as I am concerned.
But if they name if after some useless bureaucrat (like Fred Hansen)there will be hell to pay.
They are designing and building this bridge for roughly what the CRC group has spent just on planning thus far.
Just sayin’…
Al, I could care less about the MLR, but this bridge will be good for the bus lines that run on it, avoiding jams in & around the Ross Island Bridge.
Back in 2007 Ray and I tried to convince Metro and TriMet to connect the Yellow Line to the proposed Milwaukie Line through the Eastside instead of through downtown via a new bridge because it would have been cheaper to build and operate and would have generated more ridership.
We lost that argument, the bridge is under construction, so my recommendation is to now cross it with a north/south regional MAX line that would parallel I-5 from Vancouver to Tualatin.
The Yellow Line could extend through the inner eastside, over the new bridge, through Marquam and Sylvan Hills to Tigard where it could follow the WES alignment to Tualatin.
With intermediate stops at the Burnside Bridge, Inner Eastside, OMSI, South Waterfront, OHSU, Hillsdale, Multnomah Village, Barbur TC, PCC, Tigard Triangle and Tigard TC, the total end to end trip could be made in less than one hour and would greatly reduce traffic demand on I-5.
Just a thought.
It seems like if you were going to do that you would want the line to run on or east of the current streetcar alignment so that the station catchment areas are on land instead of partially water. I guess you could branch in the Lloyd district and run on 7th or one of the other streets through the Central Eastside before merging back onto the new streetcar bridge to OMSI. Its too bad we have created 2 rail systems that aren’t inter-operable
How about running it on a “highline” above the UPRR at the same level as the Morrison and Hawthorne Bridge ramps?
I think that still has the problem I was mentioning where there aren’t all that many destinations within 1/2 mile of the stations compared to having the stations along, say 6th Ave. I think it would be cool if we could get an at-grade line along one of the N/S streets, 6th, 8th, 9th that had true signal preemption, and essentially pedestrianized the street other than a MAX line running through.
Jim- would your proposal intersect the bridge ramps or go above them?
I’m curious why Jim Lee would want to name the bridge after somebody like Ray Polani, who advocated so strongly against building it. If it’s going to be named after anybody, it should be
A) somebody who was instrumental in getting the bridge planned and built, or
B) a historical or geographically relevant name such as McLoughlin or Clackamas.
It would intersect them allowing easy transfers to downtown buses. the “Highline” could also have pathways on each side of MAX for bikes and pedestrians allowing second floor access to adjacent buildings.