Mountain bikers propose park beneath new I-5 bridge.

Byline: Susan Palmer The Register-Guard

Cycling enthusiasts floated an interesting proposal for state bridge builders on Thursday when they suggested an urban mountain bike park beneath the Interstate 5 replacement bridge spanning the Willamette River.

Members of the Lane County Mountain Biking Association showed up for a public meeting about the new bridge. A temporary bridge has been handling Interstate 5 traffic since 2004, installed when cracks in the old bridge made it unsafe for big trucks.

The state Department of Transportation has finished its environmental assessment for replacing both the old and temporary bridges with two new structures designed to handle three lanes of traffic in each direction.

That assessment is available on the transportation department's Web site and the department has invited community members to comment on it through Feb. 19.

Two public meetings on Thursday, one in Eugene and one in Springfield, gave residents the opportunity to review the bridge plans, see some preliminary designs and get a better understanding of how the state will minimize the environmental impact of the construction process.

Besides crossing the Willamette River, the bridge runs along Alton Baker Park. Bike paths and a canoe canal also run under the bridge.

That bike path caught the attention of Anthony Beck and Dave Roth, members of the mountain biking group. While Oregon has some great places for mountain biking, they're all a considerable distance from urban areas, Beck said. An urban mountain bike park, similar to one under a Seattle I-5 overpass, would allow young riders from both Springfield and Eugene easy access via the already existing bike paths.

ODOT project liaison Tim Dodson seemed open to the proposal and promised to help Beck and Roth by providing them with maps of the area. He encouraged them to sketch out their ideas for a park.

Eugene architect Eric Gunderson also dropped by the Eugene meeting to encourage ODOT to develop a compelling design for the bridge.

ODOT has roughed out four basic design options, from a straightforward girder bridge with no arches above the road to a more elaborate road deck with arches rising above it.

ODOT will offer more public meetings inviting community input on the design in coming months, Dodson said.

Construction on the $180 million project should begin in 2009 and end in 2012. It will include two spans, each capable of carrying three lanes of traffic, but striped for two lanes.

Average daily traffic volume is about 49,000 vehicles and is predicted to increase to 73,000 by 2030.

For more information about the bridge, check ODOT's Web site at www.oregon.gov/ODOT/HWY/REGION2/I-5WRB.shtml.

For more about the mountain bike group, visit www.lcmba.org.