Magnolia Bridge rehab not so cheap after all: Fix job added to replacement alternatives

At a price tag of $178 million, fixing up the Magnolia Bridge would be almost as expensive as replacing it, according to current Seattle Department of Transportation estimates.

And the newly released rehab price doesn't include the ongoing costs of maintenance work needed because the bridge wouldn't be new, said project manager Kirk Jones.

As a potentially cheaper option, rehabilitating the aging and damaged span was included in the mix of alternatives earlier this year after the price of three replacement options ballooned to around $200 million each from 2002 estimates of $100 million to $130 million, SDOT director Grace Crunican said at the time.

The replacement figures have been refined since earlier this year as well. At a cost of $196 million, Alternative A would see the bridge replaced just to the south of the existing one. Alternative C, at an estimated $214 million, would include a combination of bridge ramps and - at the north end of Interbay - surface roads.

Alternative D would cost $213 million and would see the construction of a new bridge that would arch north roughly 500 feet from the existing bridge but keep its existing connections at 15th Avenue West and Magnolia.

"A and D are floating to the top," Jones said of the alternatives generally favored by the public. But there will be a painful neighborhood downside to any of the alternatives.

A traffic nightmare

"The existing bridge will be kept open as long as possible," Jones said at a project open house held at Catharine Blaine School on Nov. 29. But at some point, he noted, the bridge will be out of commission, forcing an estimated 14,500 daily vehicle trips onto the Dravus Street and the Emerson Street bridges.

For how long depends on the alternative. Alternative A would close the bridge for around 16 months, Alternative C for approximately 11 months and Alternative D for about nine months, Jones said.

But the first step needed for the rehabilitation alternative would be to remove the entire bridge deck so that other work on the supporting structure could be done, he said. "That would be the longest closure." Indeed, according to SDOT estimates, the bridge would be out of service anywhere from 21 to 27 months.

The rehab work would include installing new steel bracing, building a new supporting beam at ground level, encasing the existing columns in steel, driving a series of new pilings as deep as 100 feet underneath the bridge, and injecting cement into the ground below the bridge and 30 feet out from the edges, Jones said.

Injecting the concrete into the ground would help stabilize it and prevent its "liquefaction" during an earthquake, Jones explained. "We would have to do that almost the entire length of the structure."

The steel bracing and casing also would have to be repainted every 10 to 12 years because of the corrosive effects of the salt air, he said. "Just that alone is a substantial cost."

Jones said he was comfortable with the cost estimates for each of the alternatives, but he qualified that assertion. "All of these cost estimates are based on us being able to start (work) in spring of '09." Delays would drive up costs $4 million to $5 million a year, Jones cautioned.

The funding factor

One cause of delay could be finding funding for the project, and no sources of the money have been nailed down yet, he conceded. "It's not going to be any one source."

Possible sources include the federal government, the state, the Burlington Northern Santa Fe Railroad, the Port of Seattle and the city, Jones said. "They're still looking at what might be a local bond issue," he said of the city.

Mayor Greg Nickels has been lobbying the state legislature for funding, according to SDOT presentation materials. But that was news to 36th District State Rep. and Magnolia resident Helen Sommers, who was chair of the House Appropriations Committee last session.

"I do not know of any requests for money from the state for the Magnolia Bridge," she said, sounding doubtful that any would be available. "Given the $2 billion going to the Seattle area for the (Alaskan Way) Viaduct, I would be very surprised."

Federal funding is being sought for the viaduct project, according to the city, but federal funding for the Magnolia Bridge would come from different pots of money because the viaduct is a state road, Jones said.

The availability of funding for the bridge will also have an effect on planning for the project, he said. Planning for the Magnolia Bridge project has been funded with $9 million in federal money and $1 million from the city.

Approximately $5 million of that will have been spent by the beginning of 2007, and the remaining $4 million will be enough to complete 50 percent of the planning, according to SDOT estimates. An additional $4 million will be needed to complete the plans, Jones said.

A source for that remaining $4 million needed to complete the second half of planning hasn't been identified yet, but SDOT wants to hold off on securing and spending that money, he said. "We think 50 percent is the right point to stop if we don't have money to move ahead (with construction)," Jones added.

That's because engineering standards might change before construction can begin, meaning more money would have to spent on revised planning, as happened with the Spokane Street Bridge project, he said.

The next step in the process is for the project design team to make its recommendation for a preferred alternative to SDOT director Crunican, Jones said. That should happen this month, he added. "Then she'll be talking to the mayor."[[In-content Ad]]