Archive | Bridges

Third Time the Charm?

After being rained out two weeks in a row, Multnomah County is going to try one more time this weekend to close the Burnside Bridge to setup for the upcoming maintence project. Good luck…

After being rained out two weeks in a row, Multnomah County is going to try one more time this weekend to close the Burnside Bridge to set up for the upcoming maintence project. Good luck…

The Burnside Bridge will be closed to road and sidewalk traffic from 8:00 pm on Friday, January 20 until as late as 6:00 am on Monday, January 23 to allow a contractor to set up traffic control and a work zone for a two-year construction project that begins this month. The bridge will be closed to motor vehicles, bicyclists and pedestrians but will still open for river traffic. TriMet bus routes 12, 19 and 20 will use the Morrison Bridge during the closure. The bridge will reopen before Monday if work is completed early.

The start of field work has been postponed twice this month due to inclement weather. The contractor has made arrangements to set up the work zone and place new lane stripes in the rain if necessary, so this weekend’s closure will not be postponed.

When the bridge reopens there will be a single lane of traffic in each direction and a path for pedestrians and bicyclists on each side of the bridge. Several traffic lanes will be closed so that the contractor can begin to replace the worn concrete deck on the lift span. The $9 million project will also repair or replace parts that allow the 79-year-old bridge to open. Both repairs are critical to the drawbridge’s operation.

Bridge Work Rained Out… Again

The weekend closure of the Burnside Bridge to change lane marking for the upcoming maintence work is rained out for the second weekend in a row. The plan is now for next weekend…

Updated: A Pain the Bridge

Update:

This weekend’s closure has been postponded due to the weather, and tentatively rescheduled to next weekend

For those of us who just finally got that sense of relief that two years of maintenance on the Broadway Bridge are over (or who suffered through the projects on the Hawthorne or Ross Island bridges before), here we go again. The press release for several years of work on the Burnside Bridge follows.

This raises a couple of questions in my mind:

1) Is the stretched out process of doing the work while keeping some travel lanes open really worth it? I know the County has done good community outreach on this question, but I still have to wonder…

2) The drain on Multnomah County to keep the Willamette bridges in good condition is enormous. Isn’t it time to recognize that these are really regional resources (how many folks from Washington, Clackamas and Clark countries travel them every day) and figure out a way to share the load? Maybe that would let us actually get to replace the Sellwood…

What do people think?

Two years of Burnside Bridge lift span repairs begin with weekend bridge closure

The Burnside Bridge will be closed to road traffic from 8:00 pm on Friday, January 6 until as late as 6:00 am on Monday, January 9 to allow a contractor to set up traffic control and a work zone for a two-year construction project that begins this month. Pedestrians and bicyclists can cross the bridge but may experience brief delays this weekend. TriMet bus routes 12, 19 and 20 will use the Morrison Bridge during the closure. The bridge will reopen before Monday if work is completed early.

The $9 million project will complete two technically challenging repairs to the lift span. The concrete deck of the lift span is worn from 79 years of use and will be completely rebuilt. The Burnside Bridge has one of the largest concrete decks of any bascule drawbridge in the world. At less than five inches thick the deck is also extremely thin for a concrete deck that is stressed and flexed by regular openings.

Rebuilding the deck while keeping the bridge open to road and river traffic is one reason the project will last two years. The contractor, Advanced American Diving Service, will need to keep one leaf of the lift span operable so the bridge can open for river vessels. In order to keep the bridge open to road and river traffic, the new deck will be built in four stages (two per lift span leaf). Each stage will require one month of curing time before the new concrete is hard enough to handle the stress of traffic and bridge openings.

Multnomah County and the City of Portland studied the option of closing the bridge to traffic to shorten the construction schedule. A traffic study determined that other bridges could not absorb the 45,000 vehicles that use the Burnside Bridge each day without creating an unacceptable level of gridlock across a wide area.

The project’s most difficult stage will be the replacement and repair of mechanical parts that help open the bridge. One eighty-year old hinge that attaches the 3.5 million pound counterweight to the lift span has broken and cannot turn freely. Stress from the frozen hinge is causing the eastern leaf of the bridge to open slower than the western leaf. If the hinge were to fail, the leaf would not be able to open and the counterweight could become detached from the lift span.

Replacing the hinge assembly will require the contractor to detach the counterweight without letting the lift span deck tumble into the Willamette River. A complex rigging system will be needed to support the counterweight when it is disconnected from its hinge. Because the bridge was not designed to be repaired, the repair will require the contractor to cut away sections of the concrete counterweight and bridge walls. The repair may be the first of its kind, due to the Burnside’s rare design.

The project will also update electrical wiring, replace lift span motors, install storm water collection and treatment facilities, and replace or repaint corroded steel.

While the project will create inconvenience for bridge users, it will extend the life of the historic bridge. Replacing the Burnside Bridge would cost at least $170 million today.

Federal funds are paying for approximately 70 percent of the project, while Multnomah County is contributing the rest. Construction is scheduled to be completed by the end of 2007.

During most of the project, the bridge will be reduced from five to two traffic lanes, with a single lane in each direction. TriMet bus routes 12, 19 and 20 will continue to use the bridge and both sides of the bridge will be open to pedestrians and bicyclists. The project will require several weekend bridge closures to road traffic, each lasting three to five days, for concrete deck pours.

There will be brief closures to river traffic at off-peak times. During most of the project only one bridge leaf will be operable for bridge openings. A tugboat will be provided for river vessels that need assistance passing the bridge during a single leaf opening. Both lift span leafs will be operable if needed by the Rose Festival fleet. The Rose Festival Grand Floral Parade will also be able to cross the bridge in 2006 and 2007.

OBEC Consulting Engineers of Oregon designed the repairs, with assistance from mechanical engineering consultants Hardesty & Hanover. Multnomah County maintains the Burnside Bridge and more than 300 miles of roads and bridges. For project updates call 503-988-4884.

Sellwood Bridge: Can’t Get No Respect

I recently attended a meeting of the Portland Freight Advisory Committee, where the Freight Master Plan was being reviewed.

Once again, the Sellwood Bridge came up. The line of discussion: it’s not a freight project, so don’t list it as a project it in the master plan, and certainly don’t spend any funds targeted on freight on it!

The basis of this argument is that as long as the bridge is only two lanes, and Tacoma Street is only two lanes, this is not a freight-friendly corridor. Arguments were advanced to reconsider the option of a new bridge south of the existing one (through the Waverly Country Club) or to rebuild the Sellwood with four lanes on the assumption that sometime during the bridge’s 100-year-expected-life we’ll wise up and widen Tacoma.

[Credit goes to PDOT staffer John Gillam who reminded the committee of the local delivery function the Sellwood bridge – even at two lanes – DOES provide for the movement of goods and services.]

Of course, this is exactly the thinking that caused the Sellwood Bridge to get zero funding from the state OTIA process, even though it scores 2 on a soundness scale of 100 (presumably it will get marked down to zero when it falls into the river).

Meanwhile, the bridge remains the top priority for bicycle and pedestrian advocates as the weakest link in our network for alternative modes.

So perhaps we should develop a plan for a bike and ped only bridge? After all, we wouldn’t want to spend any of our precious bike dollars on something those stinking cars and trucks could use!

When will we get our thinking out of these single mode buckets and learn to think about multi-modal systems? That’s the only path to assembling the funding required to actually do something about this failing bridge.