The nuts and bolts of removing old bridge’s nuts, bolts and concrete

The in basket: As I crossed the Warren Avenue Bridge in Bremerton one recent day and looked over at the old Manette Bridge, fated for demolition this fall and winter, my thoughts flashed to the fact that most of the fallen portions of Galloping Gertie, the original, short-lived Tacoma Narrows Bridge, are said to remain where they fell, at the bottom of the narrows.

I wondered if any part of the Manette Bridge would wind up on the bottom of its narrows.

The out basket: It was a timely curiosity, as state engineers were grappling at that very moment with ways to make sure the answer is no, the old Manette Bridge will be removed in its entirety.

They turned out a news release soon afterward, detailing how the underwater portions of the old bridge will be removed under a separate contract. Their original plans for the removal were judged too likely to make the crumbled concrete unretrievable. There was a story about it in the Sept. 17 Sun.

Project Engineer Jeff Cook has provided me with further details.

The majority of the removal will be done under the construction contract with Manson-Mowat.

The road surface already has been removed.  This fall, the steel parts of the bridge will be lifted in chunks of up to 250 tons, put on a barge and cut up for transport off-site. The steel center truss, the visual identity of the old bridge, will be the last steel part removed.

Then crews will use what’s called a hoe ram, described as a huge jackhammer, to “rubblize” the above-water parts of the concrete uprights that support the bridge.

The chunks will fall onto a platform of planks laid between two barges to be positioned on each side of the pier being destroyed, Jeff said. The barges and planks will be covered in sand to keep the falling detritus from bouncing into the water.

When the platforms hold as much as they can, the barges will be moved to Tacoma to be unloaded, Jeff said. It may take more than one trip.

“Nothing is allowed to drop into the water,” he said. “The contractor will be required to fully contain all pieces that are picked and removed during demolition.”

The below-water parts of the bridge will fall to the bottom, but will be contained within steel coffer cells that will limit the area from which the rubble must be removed, Jeff said.

No one will ever accuse me of being an environmentalist, so I’m anxious to hear from those who consider themselves to be whether this doesn’t all seem a bit much. Particularly, the importance of keeping out of the water crumbled parts of concrete structures that have sat intact in that same water for 80-some years seems like costly overkill.

10 thoughts on “The nuts and bolts of removing old bridge’s nuts, bolts and concrete

  1. Seems like the underwater portion may have become habitat for creatures over the last 80 years. Seems like they maybe destroying it. I guess you’re damned if you do and damned if you don’t

  2. Travis, when I was a little kid I lived on E 30th st. Enetai creek ran through our neighborhood. I used to splash and play in that creek. I caught crawdads, built dams and had a blast. I didn’t know that I was destroying salmon spawning beds. Today we are told to stay out of Enetai creek because playing in it’s water could make us sick.

    We moved out to Central Valley and I found even more woods and creeks to play in. We used to watch salmon spawn up every creek and drainage ditch in the area. We also had pets, but never bothered to clean up pet waste. We didn’t know that pet waste could poison local streams. Nowadays salmon only spawn in a few streams.

    As a teenager we used to row out to the Agate Pass bridge where we could catch Red Rock fish two at time. We didn’t know that rockfish live to be 120 years old and that over fishing would put them in danger of extinction.

    In my senior year of high school I took SCUBA lessons at Olympic College. We dove off the Illahee town dock on the tire reef. It was thought the tires would provide habitat for marine life. But it didn’t work and they actually caused harm to the environment and are being removed in many places.

    To be honest, the idea of leaving some old concrete on the bottom of Rich passage doesn’t sound like a big deal to me. But neither did those other things. I’ve been watching this project and it seems to me the folks working on it know what they are doing. I’ve been impressed with the quality of their work and the fact that they are on schedule and within budget. I’m pretty sure they hired folks who knew what they were doing when they planned removal of the old bridge. I’m just gonna have to trust they know more about it than me.

    Besides my dad always taught me to leave a place the way I found it, and that’s what we will be doing in Rich passage.

  3. Why remove the pylons at all? They’ve been there for decades with no apparent adverse impact. And how can concrete be a hazard to the environment? Looks to me like it’s just another example of willful waste by the state, or malicious compliance to some vague environmental clause.
    Since the old bridge had to be shut down to build the new one, how long will the new one be closed to dismantle the old one?

  4. “…hear from those who consider themselves to be whether this doesn’t all seem a bit much. Particularly, the importance of keeping out of the water crumbled parts of concrete structures that have sat intact in that same water for 80-some years seems like costly overkill.”

    I think of myself as an environmentalist, but the excessive care to remove tiny bits and pieces of the concrete is running up the bill without justification – or so it seems to me. The fish and environs have adapted after 80 years.

    I’ve heard that concrete takes fifty years to set up. If so, it may take another fifty years to disintegrate and seems pointless to do this. Who makes the money doing it?

  5. Actually, according to the article Jeff Cook, the States project manager, said. “The changes shouldn’t affect the project’s $60.6 million cost…”

    He also said it would not delay the opening of the new bridge, but it would take a little longer to complete demolition of the old bridge. He also pointed out that. “In the meantime, navigation lights will be installed on the six pier stubs.”

    Read more: http://www.kitsapsun.com/news/2011/sep/16/demolition-of-old-manette-bridge-will-take-than/#ixzz1YoTOQIge

  6. “It was decided to contain the work within steel plates called coffer cells. That will require a new contract and postpone the final stage of demolition. In the meantime, navigation lights will be installed on the six pier stubs.”

    Well its beyond my experience that a job requiring a new contract and that postpones the ‘final stage of demolition’ would of course cost more money.
    What a welcome treat. Makes me wonder if we overpaid to begin with…?

  7. Sorry – meant to say “… its beyond my experience that a job requiring a new contract, adds new steps and that postpones the ‘final stage of demolition’ wouldn’t cost more money.”

    Gosh – I may begin to believe in the ‘free lunch’ principle.

  8. In response to Gary Reed, Project Engineer Jeff Cook says, “Once the new Manette Bridge is opened to traffic, it will stay opened to
    traffic throughout the demolition of the existing structure.”
    When I asked if the demolition work might have an up-front impact, delaying the new bridge’s opening, he replied, “The opening of the new bridge is not dependant on any of the demolition
    work.”

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