WSDOT-wiki vs KOMO-leaks: What to know regarding 520 pontoon cracks *UPDATED*

Media tour inside a new 520 Bridge pontoon. Image: WSDOT Flickr stream

Since KOMO started reporting on construction problems with the new 520 Bridge, WSDOT has started a media campaign to put to rest public fears about leaky pontoons. State Secretary of Transportation Paula Hammond is confident that these first six pontoons will be repaired and has said, “We won’t accept the pontoons from our contractors until we are satisfied they meet contract specifications.” And yet, Governor Christine Gregoire is taking no chances: she has called for an independent panel of experts to review the project.

For background, a summary of KOMO’s reports:

  • October 26: All six of the first pontoons have “extensive cracking” and delays could cost the State $90,000 per day.
  • November 1: The 360-foot longitudinal pontoons are missing steel reinforcing (aka “hook bars”) at the end joints that link them together.
  • November 9: Internal documents from WSDOT engineers raise more red flags; videos and documents posted online.

WSDOT responded by publishing a website dedicated to 520 construction issues, kicking off a Wikileaks style arms race for transparency, including:

  • KOMO’s full 25-minute interview with Paula Hammond + email correspondence.
  • 45 hours of pontoon inspection videos.
  • Highlights from a November 14th media tour of the pontoons + press release on repairs and structural omissions.

Sensational cover up? Or the fog of bridge building? Even local media seem to have conflicting reports on this one. On November 13th (the day before WSDOT’s media tour), The Seattle Times reported WSDOT’s progress in repairing cracks in the pontoons’ outer walls was all good news:

The big end-piece W, where columns are being built, was still seeping after it reached Lake Washington, according to an Aug. 27 [contractor] Kiewit letter to DOT.

Since then, all known cracks in the outer walls have been treated, said DOT project manager Julie Meredith. “The fact (water) it’s not coming through those cracks now is a very good sign,” she said Friday, while walking on a lengthwise pontoon.

The next day, KOMO reporter Tracy Vedder tweeted:

WSDOT confirms 4 biggest pontoons still leaking


It’s unclear if Vedder was referring to outer wall leaks or internal wall leaks. During construction, the pontoons’ interior cells hold water for ballast which will eventually be replaced with gravel — so interior wall cracks are less critical than exterior cracks.

And now there’s more…

Tonight KOMO will air an interview with a former WSDOT quality control inspector who says the 520 Bridge project is a “disaster waiting to happen.” They also have uncovered a state audit that further confirms problems with the pontoons’ integrity. WSDOT has preemptively posted an email response to KOMO regarding their (as of now) anonymous source:

We just don’t know enough about this person’s previous role on the pontoon project to respond in a meaningful way to the assertions he (based on your verbal description) has made.

It is important for you and KOMO to understand and convey to your audience that there is a rigorous quality program in place at the pontoon project as required by the WSDOT contract with Kiewit-General.

Preemptive media control — and hype — aside, the interview airs tonight at 11pm.

UPDATE: November 20

KOMO’s full report and interview from last night are posted here.

And today, KOMO’s crack reporting continued. They have confirmed that the second batch of pontoons under construction in Aberdeen have also shown extensive cracking, before they’ve even left the casting basin. These “cycle 2” cracks are in precast interior wall panels which are less critical than the exterior walls, yet still, WSDOT Kiewit has rejected several of them as unfit for pontoon duty.

UPDATE: November 21

Today WSDOT released the following explanation for “cycle 2” pontoon cracks:

Crews working in Aberdeen on cycle 2 of the pontoons for the new State Route 520 floating bridge have completed construction of 345 pre-cast concrete wall panels. Contractor Kiewit-General has rejected nine of these walls as part of their quality assurance and quality control processes required by the Washington State Department of Transportation in its pontoon contract.

These nine panels had not yet been installed inside the pontoons. They were discarded and new concrete panels were poured. Of the nine panels discarded, three exceeded the contractual limits for cracking and six were rejected due to a duct alignment issue. Approximately 90 percent of the panels have been placed to date.

Again, it should be noted that these wall panels are for interior cells and are not part of the (more critical) exterior pontoon walls. A primer on interior wall leaks is available here.

3 thoughts on “WSDOT-wiki vs KOMO-leaks: What to know regarding 520 pontoon cracks *UPDATED*

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