By Tracy Record
West Seattle Blog editor
“This has been bad. It’s been awful for West Seattle. And there’s no immediate fix … no matter what options we take here, we’re in this for a number of years.”
That’s part of what Mayor Jenny Durkan told the West Seattle Bridge Community Task Force today at its 10th meeting, two weeks before she is expected to announce her choice between “repair now and replace later” or “proceed directly to replacement.”
But the centerpiece of the meeting came in toplines from the report that is supposed to shape her decision, along with input from the CTF and the Technical Advisory Panel: The Cost-Benefit Analysis (CBA). And members voiced concern that it doesn’t give enough consideration to the misery the mayor mentioned. The toplines presented by SDOT seemed to be leaning toward “proceed directly to replacement,” but without some key information: Cost estimates in dollars, and cost estimates in impacts to area residents and businesses.
Though the mayor spoke first, as one CTF member observed, it would have been more helpful for the CBA toplines to have been presented first, so that’s where we’re starting, right after the meeting video:
(Note: Meeting stopped for 15 minutes starting 55 minutes in due to technical trouble)
COST-BENEFIT ANALYSIS: Technical Advisory Panel (TAP) co-chair Barbara Moffat (a vice president at Stantec) noted that the TAP is both an input-giving group in the repair-or-replace decision, and has helped shape it themselves. The TAP is now coming up with the pros/cons – “a guidance document” – of what’s in the CBA. “All the alternatives that have been considered in the CBA are technically feasible from an engineering standpoint …. (but) a dollar figure is not the only consideration,” Moffat noted, while reiterating that, after the upcoming decision, the CBA will not be the determining factor of HOW the bridge would be repaired/replaced. She also noted that SDOT’s interim roadway structures director Matt Donahue was also advocating for consideration of ‘asset management” as decisions are made.
Here are the considerations they’re weighing:
Regarding that last point, Moffat said that information “is not critical” for decisionmaking.
City Councilmember Lisa Herbold. one of several elected officials on the CTF, noted at that point that it’s important to note that what the TAP said previously wasn’t that repair is feasible so much as that nothing was found to suggest repair was infeasible. Moffat acknowledged that was a sort of double negative. Herbold expressed concern that the decision was to be made before technical information was available about the bridge’s response to colder weather and the about-to-happen release of a stuck bearing. Regarding the temperature, Moffat said that there’s a “tremendous correlation between the current models” and what actually happened during the summer, so they have a confidence level that their models and monitoring can sufficiently predict winter response. As for the stuck bearing, Moffat said the unlocking is “only a good thing” and would not play into the repair/replace decision.
CTF co-chair Greg Nickels asked about the “would a repair be good for 15 years, or 40 years” conundrum. Moffat said they developed a range – 15 to 40 – but they can’t get much more specific. To get more specific would require a much more specific, time-consuming analysis. “This is an older structure, and because one issue is fixed doesn’t mean others might not occur,” she added.
SDOT’s Greg Izzo presented the alternatives and “key factors that are influencing our recommendations.” First, a caveat – these alternatives studied for the CBA was for comparative purposes, not a full menu of options for potential repair/replacement
Alternative 1 – Shoring:
This one “does not offer a lot to us regarding longevity of service life,” Izzo warned, and it’s not the cheapest – it would last about five years. “The overall ownership costs … are in the middle of the pack. … The cost/benefit info doesn’t pencil out for us.” Another factor of risk with this – “there’s not a lot of regional experience.” And this would still be temporary, while a replacement is designed/built. Also, this would only enable 3 to 5 lanes to be restored – compared to the 7 lanes on the bridge pre-closure – and would be a “two-phase construction approach” second phase, a reference to the bridge replacement.
Alternative 2 – Repair:
The CBA suggests repairs would be the cheapest alternative but would have higher “ownership costs” over the bridge’s life, so it would still eventually cost almost as much as a replacement. Repairs, however, are “the quickest way to get traffic back onto the bridge” – mid-2022 or so, if “immediate mobilization” happened post-decision. It would last at least 15 years, they think, but could be less or more. It would not be as seismically sound as a new bridge. And choosing repairs would require another bridge closure for replacement, eventually. Izzo added, “This option does not enable what a replacement can in terms of planning for future traffic,” with West Seattle continuing to densify. And finding funding for a replacement would be harder with a repaired bridge in action, than it would be now, with a closed bridge.
He then noted that what had been alternative 3 – partial replacement – has been tossed out. “Too high of a risk to consider,” Izzo explained.
Alternative 4 – Superstructure replacement:
It’s “the middle of the pack” on capital costs, with a lower ownership/maintenance cost because it would be new. It could open by 2026 – maybe, Izzo said, a little faster if they found “alternative” ways to do it (which would require extra funding). This could last at least 50 years; after that, it would likely require strengthening. One risk here is that the U.S. Coast Guard, as previously mentioned, might require a higher bridge. “If we have to go higher with the bridge,” they’d have to deal with the approach spans too, and that would be an added cost. Other risks could include.a change in seismic requirements.
Alternative 5 – Full replacement
The CBA shows a cable-stayed bridge as the example here, not because that’s necessarily what would be built, but for comparative cost estimates. The risks/benefits here have a lot in common with #4 -they too could take until 2026 but they would try to find “alternative” faster ways. This would be a steel bridge and time of fabrication is something else to consider. Finding funding for a bridge replacing a closed bridge would be easier.
Alternative 6 – Immersed tube tunnel
Izzo first noted that they’re evaluating this with a potential route on the north side of the current bridge. It would have the highest capital costs because of the cut-and-cover section it would require across Harbor Island as well as because of the immersed tube itself, plus other connections. The maintenance costs “given the amount of HVAC and (other) systems .. will be quite high” and the lack of experience with it also would add to that. It would take the longest period of time to build; they project 2030. And that’s WITHOUT consideration of adding light rail, which would require “an off-site casting facility.” Other risks would include “a lot of casting on site” of the cut-and-cover sections and in “trenching across the island.” Getting enough funding would be “quite a challenge,” since the cost would be maybe two or more times the full replacement.
In summary, the attribute comparison:
And then the bottom lines and “key takeaways”:
Here’s what would happen if repair is the choice
Or if replacement:
“Designing a replacement is going to be necessary even if we repair and reopen” the current one, bridge project director Heather Marx underscored.
In CTF discussion – co-chair Paulina López and Greg Nickels suggested an extra meeting next week to hear opinions, since a technical glitch cost some time in the meeting. The CTF feedback is framed as “what are the most important things the mayor should consider?” rather than polling everyone “repair or replace.”
So instead Nickels asked a question about alternatives 2 and 4 – whether each dollar sign on the slides represented an equivalent cost value. No – #4 is probably “5 to 10 times the cost of alternative 2,” Izzo said. #4 meantime would be about half the cost of #2.
SDOT director Sam Zimbabwe jumped in on that. It’s all “big numbers,” he noted, but reminded everyone that they’re making comparisons “at zero percent design level” so “any number we put out right now would likely be incorrect,”so the comparison is more important than the specifics.
Nickels noted that the four years that would be saved by the repair option look priceless in their value to people’s lives, but it’s hard to weigh that without knowing the actual dollar estimates too.
“That type of feedback is exactly what will be helpful” in decisionmaking, Zimbabwe said. But the repair option “does come with a level of uncertainty” about how soon the bridge would subsequently have to close again for replacement.
CTF member Jen Temple of West Seattle Bridge NOW said, “The choice seems fairly obvious” for repairs, given the effects on people’s lives, and criticized the fact no “economic modeling” has been done to factor in the costs of closure.
CTF member Anne Higuera of Ventana Construction (WSB sponsor) wanted clarification on how long a replacement closure would take if repairs are done first – would the eventual replacement closure be shorter? “It would depend on what kind of replacement, what kind of delivery mechanism,” said Marx. She also said there are different possibilities for alternative 4 that could take different lengths of time – so that’s why they’re trying to hone in on community values – do people want something done ASAP no matter what? for example. (In response to CTF member Charlie Able‘s similar question later, it was also noted that permitting time would play into the length. Able said he just wanted to clarify, even if fixed now and replaced later, there would still be a closure – yes, Zimbabwe said, because they would almost certainly be using the same alignment.)
Peter Steinbrueck, Port of Seattle Commissioner, suggested it was unfortunate the CBA presentation hadn’t preceded the discussion with the mayor. How are they going to be able to inform the mayor’s decision once they have more details? “I can’t help but feel that the repair option is being shortchanged on a couple levels,” he suggested, especially given that the cause of the bridge’s current problems still has not been determined. And what about, say, an option 2-plus, with repair and some upgrading, he wondered. “Sometimes these analyses can lead to a hybrid,” and that’s what he hopes will be considered. He also suggested that the funding possibilities shouldn’t be shown as equal across all options because different projects would have different funding sources.
At that point, Moffat said they do have a good understanding of what went wrong with the bridge, though she didn’t go into full details. “We do know what we’re fixing, and we know what we can fix,” she clarified. “We were suspecting a shear failure at joint 38 … since that time the analysis and modeling has developed what the actual failure mechanism likely is … we do have the analytics behind understanding why and what occurred.” That said, she cautioned: “With an aging structure, other issues could arise … that’s the uncertainty,” not an uncertainty over what went wrong. Remember, she said, this bridge was ahead of its time, including seismic protection, in 1980, but things have changed – such as, bridges are supposed to withstand 900+-year earthquakes, not just 400+-year earthquakes. “There is a certain limiting factor with an existing structure regarding what you can do to repair or retrofit it.”
CTF member Peter Goldman then said some parts of the tube tunnel evaluation might need to be rethought in light of what’s been done at the Fraser River, as well as the concept of whether to put Sound Transit light rail in it.
Moffat at this point reminded all that the decision is repair – 2 – or replace – 4, 5, or 6. They are not choosing what type of replacement now; the Size/Type/Location study would hone in on that. Regarding including ST, the “grade perspective” is a challenge and might require lengthening the approaches as well as a “fire life safety” consideration, with a pump station, ventilation, cross passages, maybe even a full-time staff. “There’s a lot of considerations. … As you start getting into the actual needs … those are things that a Type/Size/Location study would flesh out,” but the costs they have are “very preliminary.” “I would caution that it’s not being thrown out.”
Bottom line:
Earlier in the meeting:
CONVERSATION WITH MAYOR DURKAN: “The impacts of the bridge outage have exacerbated all the other crises we’re experiencing right now … daily impacts,” noted the mayor. She listed a variety of decisionmaking factors, while noting that any option is a significant investment of tax dollars and time.
The mayor also observed that taking maritime-industry concerns into consideration has added weight now because it’s more “critical to the future of Seattle and our region” than ever, given the recent Boeing news.
Task Force feedback: “People just want some certainty,” offered Deb Barker of the West Seattle Transportation Coalition and Morgan Community Association. Next, John Persak, representing Georgetown, pointed out that detour-traffic impacts there are unique because it’s a neighborhood without a grocery store, pharmacy, or geographic center. “Lack of internet access … (requires) more support from the city” for those working and studying at home, noted David Bestock of the Delridge Neighborhoods Development Association. “Internet IS equity,” agreed the mayor.
Diane Sosne of SEIU Local 1199, a health-care union with 1,000 members in this area, noted that the “financial impact to workers is huge.” She wondered if there’s a “hybrid” way to handle concerns, especially helping health-care workers get to their job. “We’re looking at every option,” affirmed the mayor. “Every option will be a hybrid … repair or replace.”
WS Bridge NOW’s Temple underscored the importance of certainty, and wondered why both can’t be done “in parallel” – repairing while moving ahead with replacement. “We’ve been pushing really hard not to do an ‘or’,” replied the mayor, saying the duration any option will last, and how it will work with the “built environment” such as the Terminal 5 modernization process, is a vital consideration. Goldman, a bicycling and environmental advocate, voiced concern about commenting because ‘we don’t have any numbers in front of us” in terms of dollar figures. “If you are going to look at dollar figures in a vacuum and we don’t have those dollar figures,” the CTF is being asked to “put the horse before the cart,” he said.
Lora Radford of the West Seattle Junction Association said the low-bridge passes made available to small businesses (the WSJA has access to 6.passes to be shared by its 230 businesses) have been invaluable. Marci Carpenter of the Washington Federation of the Blind said she’s hearing from transit riders that the low bridge is working OK and more van shuttles are needed, given the access challenges to bus stops amid our hilly topography. “Almost uniformly, people want the bridge to be opened as soon as possible,” but other people with whom she’s spoken don’t feel like it’s right to just “kick the replacement down the road” so someone else has to deal with a long closure like that. “How much is it going to cost, how long is it going to take, how long is it going to last,” are the three factors Durkan cited again. She also mentioned the Seattle Transportation Benefit District measure on the upcoming ballot, with some money set aside for West Seattle transit needs.
BRIDGE UPDATE FROM SDOT: Marx presented a brief update. She started with a stabilization update:
The brackets inside the box girders are being attached so the post-tensioning steel can be secured, she said, adding that contractor Kraemer NA is now working seven days a week. She also recapped some of the recent Reconnect West Seattle-related work, including Sylvan Way, West Marginal Way, Alki Trail, 32nd/Barton and 1st/Olson repaving, and the Home Zone walk earlier this week in South Park, with Highland Park and Georgetown coming up.
The low-bridge subcommittee has met once and will meet again next week, looking ahead to the installation of enforcement cameras enabling “fine-tuning” the policy.
NEXT: The co-chairs are working with members to schedule a meeting for next week devoted to discussion of the CBA, so they can get more feedback to the mayor before her decision, which she is currently scheduled to brief them on in two weeks.
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