The following is a release from the Washington State Department of Transportation:

The Washington State Department of Transportation today announced it has reached agreement with its pontoon contractor for added costs associated with building pontoons for the new State Route 520 floating bridge.

In late December, WSDOT executed five new change orders for the SR 520 Bridge Replacement and HOV Program with its pontoon and floating bridge contractors. These change orders total $42.65 million, of which $37.1 million is with Kiewit-General Joint Venture for the redesigned pontoon work on Cycles 3 through 6.

In a media briefing today, Washington Transportation Secretary Lynn Peterson and SR 520 Program Director Julie Meredith said WSDOT’s pontoon design error is consuming much of the SR 520 program’s $250 million risk reserve. One additional change order associated with the pontoon design error is expected in the next month and will likely bring the total cost associated with the pontoon design mistake to approximately $200 million. WSDOT also has signed or identified expected change orders worth $134.3 million related to other construction in the corridor.

With the signed and expected change orders, plus WSDOT’s thorough analysis of the potential future risks associated with the remaining $800 million in funded construction, the agency has determined that approximately $170 million in additional project funding is required. Peterson said the agency has identified existing funding sources to cover these costs and keep the bridge-replacement project on track.

WSDOT has determined that most of the needed construction funds can be obtained from available SR 520 toll bonding capacity, with other existing agency resources providing the remaining funds, dependent on legislative approval.

The SR 520 program’s legislatively authorized budget currently is capped at $2.72 billion. The budget covers three major projects: Eastside improvements to the SR 520 corridor from Medina to Redmond; the new floating bridge and bridge landings; and pontoon construction. The addition of transit/HOV lanes in both directions from Seattle’s Montlake neighborhood to I-5, along with other corridor enhancements on that stretch of highway, remains unfunded. WSDOT will work with the Legislature to request authority to change the program budget from $2.72 billion to $2.89 billion.

“The original pontoon design included an unfortunate and costly mistake,” Peterson said. “While the error discovered in 2012 is depleting most of the contingency reserve, we are proactively managing the remaining risks and don’t foresee the need for new funding sources to complete the work at hand and move our region closer to a safer, higher-capacity, multimodal 520 corridor.”

In 2012, WSDOT determined that repairs and modifications were needed on four pontoons from Cycle 1 as a result of a design error. In addition, all remaining pontoons required either modifications or construction using an updated design. WSDOT contractors have since completed repairs on two of the four Cycle 1 pontoons, and will complete repairs on the remaining two pontoons this spring.

When complete, the SR 520 program will replace the existing, 50-year-old SR 520 bridge across Lake Washington with a safer structure, dedicated lanes in each direction for buses and high-occupancy vehicles, a separate path along the highway corridor for bicyclists and pedestrians, and environmental improvements along SR 520 between I-5 in Seattle and SR 202 in Redmond. The new floating bridge is expected to open to traffic in late 2015 or early 2016.

More information about the SR 520 Bridge Replacement and HOV Program is available at www.wsdot.wa.gov/projects/sr520bridge.