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SR 520: Next Up Pontoons

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Full Council  10/7/2013
Agenda: Public Comment, Lynnwood Link Extension, Land Use and Zoning, 2008 Parks and Green Spaces Levy, Montlake interchange of State Route 520, Relating to the SR 520, I-5 to Medina
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SR 520 Project Committee  9/30/2013
Agenda Items: Public Comment, Program and Construction Update, Memorandum of Understanding Commitments Update, West Approach Bridge North Status Update, Washington Park Arboretum property, Washington Park Arboretum aquatic lands and waterway use, Montlake interchange
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SR 520 Project Committee  3/4/2013
Agenda Items: Memorandum of Agreement Presentation.
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One of the busiest roadways in the Puget Sound region, State Route (SR) 520's floating bridge opened for traffic August 28, 1963. Officially named the Governor Albert D. Rosellini Bridge, but more commonly known as the SR 520 floating bridge or the Evergreen Point Bridge, the structure has provided a vital link for area residents to cross Lake Washington for over four decades.

The bridge was designed for 65,000 vehicles to pass over its span each day. Currently about 115,000 vehicles pass over it daily. The bridge is just less than 2.5 miles long with nearly a mile and a-half of it floating on the water. Thirty-three pontoons keep the bridge afloat while 62 anchors help keep it in place. The draw bridge at the midspan allows large ships to pass through to the northern portion of the lake. The depth of the lake at drawspan is 200 feet.

Like any water vessel, the bridge has seen its share of blustery days on the lake. The bridge is regularly shut down when a high wind storm blows through the region. Strong wind storms have forced the closure of the bridge for several days while crews repair the damage.

The damage the bridge has suffered over the years from wind, combined with age and concerns about the structure's seismic stability, is forcing state officials to consider options to rebuild the floating bridge. The construction project will give transportation officials the opportunity to widen the bridge with the hope of easing a common spot for traffic tie-ups.

Did You Know?
The state of Washington is home to many of the largest floating bridges in the world:

  • SR 520 Evergreen Point Bridge
  • I-90 Lacey V. Murrow Bridge - The original I-90 bridge; it sank during a strong storm that had forced the closure of the bridge Thanksgiving weekend 1990.
  • I-90 Homer M. Hadley Bridge
  • SR 104 Hood Canal Bridge - The only bridge in Washington built over tidal waters. The western half of the bridge sank during a strong storm with wind gusts between 85 and 120 mph. Technological advanced made rebuilding that half of the bridge the best option for the repairs.

Design Alternatives:
Currently, the Washington State Department of Transportation (WSDOT) is considering three design alternatives for the Seattle (west side) of the bridge replacement. All three would expand the bridge from 4 to 6 lanes with two general-traffic lanes and one High Occupancy Vehicle (HOV-carpool and transit) lane in each direction, a pedestrian-bicycle path and lids at I-5, 10th Avenue E. and Delmar Drive E.

The WSDOT website describes the alternatives as follows:

Option A - Most similar to today's configuration, with the addition of a second Montlake drawbridge over the Montlake Cut.

Option K - Includes a tunnel under the Montlake Cut and a single point urban interchange below the SR 520 roadway.

Option L - Includes a diagonal drawbridge over the Montlake Cut and a single point urban interchange above the SR 520 roadway.

In order to allow the existing bridge to remain open during construction, whichever option is chosen, a new floating bridge will be built north of the current structure. The pontoons for a new bridge will be constructed off site and brought in through the Ballard Locks once they are ready to be put in place.

WSDOT currently estimates the project will cost "between $4.56 billion and $6.67 billion, depending on which west side design option is chosen."

While funding for the project is primarily through state funds, transportation officials also believe charging a toll will help to generate billions. Tolls aren't new for the bridge. When it opened in 1963, drivers paid a toll and nearly $60 million was generated until the toll was lifted in 1979. This time around, officials estimate $1.5-2 billion will be raised from tolls. The price would be fixed according to time, day and direction of travel. While no specific fee has been set, planners estimate the toll could cost $3.50 each way.

Thanks to technology, toll booths are a thing of the past. Crews would construct an overhead automated card reader that would detect a credit card size sticker on windshields. The toll would be deducted from either a pre-paid account or would be directly linked to the drivers debit or credit card account. For drivers who don't normally use the SR 520 bridge, they could go online and register their license plate with their debit account so tolls could automatically be deducted from accounts. Other options to collect tolls from infrequent bridge users are also being explored.

Other funding sources include: $550 million from the state gas tax, $110 million in federal bridge funds and $180 million in state sales tax deferral. WSDOT officials also hope to receive over $1 billion more from the federal bridge and highway funds in the future.

Project Timeline (from WSDOT):

  • 2010 - Issue final environmental impact statement
  • 2010 - Begin construction on the Eastside corridor
  • 2011 - Begin construction of new floating bridge
  • 2012 - Begin construction on Seattle (west) side of the corridor
  • 2013 - Open Eastside transit and HOV improvements to drivers
  • 2014 - Open four-lane bridge to drivers
  • 2016 - Open six-lane bridge to drivers

The Latest News:
$500 million pontoons

On June 22, 2009, the Washington State Department of Transportation (WSDOT) began the process of identifying a contractor to build 33 concrete pontoons for a new State Route 520 bridge. WSDOT plans to hire a contractor for the $300-$500 million project by December 31, 2009. The contractor will “design and construct a new pontoon casting and launching facility” as well as build the pontoons themselves, according to WSDOT. WSDOT specifies that the new pontoon facility must be located in Grays Harbor county on Washington’s coast. The pontoons themselves will be massive—21 of them will be 360 feet long by 75 feet wide by 28.5 feet deep, according to WSDOT. In April, the State Legislature authorized tolls to pay to replace the SR 520 bridge project including the cost of the new pontoons. The state Transportation Commission will set the starting date and the amount of the tolls.

Previous Updates
Legislature approves tolling for SR 520 bridge

In April 2009, the Washington State Legislature approved tolls on the SR 520 bridge in order to raise money for the structure's replacement. House Bill 2211 directs the Washington State Transportation Commission to set the amount of the tolls and to vary them by time of day, according to the final bill report prepared by non-partisan legislative staff.

In addition, the bill caps the cost of the bridge replacement at $4.65 billion. It does not, however, make decisions about which design alternative should be pursued. Instead, it creates the SR 520 Work Group that will report back to the legislature by January 1, 2010 on its recommendations for design and financing of the project. The SR 520 Work Group is comprised of 12 legislators mostly from districts that have some part of the bridge within their geographical boundaries-including State House Speaker Frank Chopp (D-Seattle), House Transportation Chair Judy Clibborn (D-Mercer Island), Senator Ed Murray (D-Seattle) and Senator Rodney Tom (D-Medina)-and Washington State Secretary of Transportation Paula Hammond.

The cost of commuting across SR520 could add up

Commuters across the SR520 floating bridge may have to shell out $10 just to get across. That's the current toll estimate from the January 29 House Transportation Committee Hearing in Olympia.

Based on the proposal, the round-trip tolls of the new Evergreen Point bridge would range from $5.66 to $8.13 in today's dollars and $6.90 to $9.90 when the new bridge is expected to open in 2015. Official estimate it could take over 40 years to finish funding the bridge.

The latest cost estimate for the new bridge is $4.38 billion. The Legislature agreed to fund $552 million and the Regional Transportation Investment District $1.1 billion if voters consent to a tax increase that will raise $8.5 billion for several road projects.

However, even with that funding the project is still $2.7 billion less than the estimated cost.

One state lawmaker said they have to respond to the overwhelming cost of the SR520 project this session.

Governor favors six-lane rebuild but funding still isn't there

Governor Christine Gregoire announced her preference for a six lane rebuild of SR 520 in a December 15, 2006 press conference, but she also admitted the state lacks the finances for the much needed project.

The six-lane option includes two transit only lanes - one for transit and carpool, four lanes for motorists. The current bridge is expected to wear out within 20 years and is often shut down during strong windstorms.

Current estimates put the construction costs ranging from $4.4 billion to $5.3 billion. Money from federal grants, tolls and gas taxes would only cover a little over $2 billion.

While many city leaders favor the six-lane option, some neighborhood groups in the Montlake area are concerned the larger bridge could have a negative impact on their neighborhood.

The proposed Pacific Interchange would deposit cars traveling west bound between Husky Stadium and the UW Medical Center. University of Washington officials are considering asking state leaders for compensation for the disruption construction would cost their campus. They say fans may stay home from football and basketball games to avoid traffic issues.

Gregoire has asked state leaders to continue work on finding additional funds for the bridge.

Six-Lane Design Front Runner for New Bridge

City Council members narrowed down the design options for the new SR 520 bridge, opting for the two six-lane designs. Both versions of the bridge have four lanes for general traffic with two lanes reserved for transit/HOV lanes.

The Council will continue to work with WSDOT on design and financing options. Council members have also reserved the right to keep a four-lane option as backup if certain issues can't be addressed.

Council members are expected to make a final decision on the city's preferred alternative in mid-October 2006. After that, their decision will be passed onto the SR 520 Executive Committee, a regional advisory body designed to make their own recommendations for Governor Chris Gregoire. Their recommendations will be given to Gregoire by the end of the year. Both Council members Richard Conlin and former councilmember Jan Drago were members of the SR 520 Executive Committee.

Financing Options Reviewed

The group charged with taking a closer look at the proposed SR 520 redesign and construction said the finance plan falls short of what may be needed to rebuild the bridge across Lake Washington.

The Expert Review Panel released their report of Washington State's Department of Transportation financing plan stating, "We find it unreasonable to assume the project will realize sufficient funding from secured and anticipated funding sources." The report was released on August 31, 2006.

A six-lane rebuild, which is the option the review panel studied, is estimated to cost $3.1 billion. The report states the funding premise is overly optimistic about securing the fund need to complete the project.

Governor Gregoire has instructed the Legislature to begin working on finding the state's share of finances as well as assessing ways to get public and private financing.

For more information, read the Expert Review Panel's full report.

In early June 2006, an independent expert panel was created to review the construction and finance options of the SR 520 floating bridge and the Alaskan Way Viaduct/Seawall projects. The panel consists of eight experts in the fields of planning, engineering, finance, law, emerging transportation technologies, geotechnical and economic fields. Governor Chris Gregoire convened the panel since millions of state, local and federal dollars will be used to complete the projects.

The panel is expected to begin meeting in late June or early July 2006. Some of their meetings will be open to the public, but others will be a closed work session. They are expected to submit their report in September that will help inform state and city officials whether the plans to replace the two main arteries through the Seattle area are achievable.

Who's Involved:

Neighborhood and local groups involved with planning:

  • Greater University Chamber of Commerce
  • Laurelhurst Community Club
  • Montlake Community Club
  • Portage Bay/Roanoke Park Community Council
  • Ravenna/Bryant Neighborhood Association
  • UW Regional Affairs Office
  • North Capitol Hill
  • Madison Park

Additional Resources:

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