Herbold: Offers three updates on West Seattle Bridge Community Task Force Meeting
Fri, 10/16/2020
District 1 City Councilmember Lisa Herbold shared updates on what she learned during "in-between" meeting on Wednesday of the West Seattle Bridge Community Task Force and a preview of what will be shared on Monday and next Wednesday during the regular meeting.
At the meeting of the West Seattle Bridge Community Task Force on Wednesday, we received three important updates from SDOT regarding the decision on whether to repair or replace the West Seattle Bridge.
First of all, SDOT Director Zimbabwe announced that SDOT will release the final Cost Benefit Analysis (CBA) on Monday. The CBA is developed to inform the decision whether to repair or replace the West Seattle Bridge. It’s critical for the members of the task force (and the public) to have this information, in order to fulfill their intended function of providing advice about the decision. Members of the task force expressed frustration last week at the amount of information they had received, and not having cost estimates beyond dollar signs from one to five, for both construction and maintenance and operations. I’ve heard the CBA is approximately 80 pages, and will likely be released Monday, so it will be challenging for task force members to digest by the next meeting on October 21st. There will likely be another meeting added the following week to better allow members to fulfill the function of providing informed advice.
Secondly, given the timing of the availability of the CBA, the Mayor is no longer expected to announce a decision at the task force meeting on the 21st.
Third, SDOT Director Zimbabwe announced their design contractor, HNTB, has brought forward a replacement alternative based on the Lake Champlain Bridge, a two-lane bridge between New York and Vermont which opened in 2011. Here’s a "white paper” prepared by the two state transportation agencies and the Federal Highway Administration, available at the NYDOT project page. SDOT will be presenting about it at the task force meeting on Wednesday; I have not received any information about this beyond what is publicly available.
The replacement options considered to date have been presented to inform the decision whether to repair or replace the bridge; a Type, Size and Location study will be needed to decide what replacement would be used. The options presented so far include estimated opening dates in 2026, compared to 2022 for a repair. There’s been a suggestion that a new “rapid replacement” option could potentially be done in three years.
According to the white paper, the Lake Champlain project was completed in shortly over two years, through approaches on permitting, design and construction, and demolition of the bridge.
The white paper notes there was an unusual amount of close cooperation on permitting, including with federal agencies, and between federal agencies. A design-bid-build process was used, which can save time compared to standard processes.
Environmental review was condensed to five months, rather than e.g. 5+ years. No EIS was required; the project was able to receive a “Categorical Exclusion with Documentation;” it was built along the same alignment as the original bridge.
Off-site construction was used to build bridge elements, and brought into place on a barge; the center span was raised 75 feet.
In addition, the previous bridge was demolished (see 40 seconds in), and went into the lake.
The white paper indicates 80% of funding was provided by the federal government, with the rest split between the two states.
Compared to that project, there is a more challenging environment adjacent to the West Seattle Bridge, with the Port of Seattle and numerous adjacent maritime businesses, a salmon run and Native treaty fishing rights, and an urban environment. In addition, much of the bridge is above land. It’s hard to see approval for any permitting to demolish the bridge into the Duwamish, for example. In addition, conceptual options for replacement presented to date by SDOT for Superstructure Replacement and Full Replacement include replacing portions of the bridge that are over land. An earlier option to replace only the center span (which is mostly over the water) was deemed infeasible.
While it’s unlikely all these conditions of the Lake Champlain Bridge could be replicated for the West Seattle Bridge, it’s important to learn what we can about accelerating timelines from other projects, as well as innovative approaches toward permitting and interagency coordination whether we proceed with a repair or a replacement.
Permitting Risk and BNSF Rail Bridge
Schedule and permitting risks are an important element of the West Seattle Bridge decision. One of the risks mentioned in the cost/benefit analysis is permitting, e.g. vertical clearance required by the US Coast Guard.
In this spirit, recent developments on the ship canal rail bridge are worth keeping in mind. Last week BNSF Railroad announced they will be repairingthe 1914 railroad bridge over the ship canal.
Two years ago BNSF had announced they planned a new bridge, with a vertical lift span, that would have 155 feet of vertical clearance, 15 feet more than the West Seattle Bridge
I have heard that the Coast Guard may have wanted additional vertical clearance beyond that. So I believe the risk re: delays for Coast Guard permitting must be fully vetted, and strongly encourage SDOT to contact BNSF re: their experience. We cannot end up in that kind of position two years from now, deciding to change course.
Survey says?
On October 12 at approximately 7 p.m., I conducted an online survey asking whether people support a repair or a replacement of the West Seattle Bridge.
It’s not a scientific survey, and geographic responses aren’t representative of District 1 overall. That said, it is useful for receiving feedback from constituents at this point in time. Thank you to all who engaged.
As of 7 p.m. on October 14, approximately 7,000 people had participated and of them, 59.8% favored repair, 36% supported replacement, and 4.2% supported other.
39% of replies were from 98116, the zip code furthest north in West Seattle. Other zip codes, such as 98106 and 98126, stretch from north to south, 98126is in the central portion, 98106 in the eastern portion. 98136 is the SW portion of West Seattle, and 98108 includes South Park. 98146 includes the very southwest portions of the city.