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Interstate Bridge
Carries Interstate 5
Crosses Columbia River
Locale Portland, Oregon to
Vancouver, Washington
Maintained by ODOT, WSDOT
ID number 01377, 07333
Design Dual truss with vertical lifts
Total length 3,538 ft (1,078 m)
Longest span 531 ft (161.8 m)
Vertical clearance 15.5 ft (4.72 m)
Clearance below 72 ft (21.9 m) closed,
176 ft (53.6 m) open
AADT 124,500
Opened February 14, 1917 (Northbound),
1958 (Southbound)
Vancouver-Portland Bridge
U.S. National Register of Historic Places
Interstate Bridge is located in Oregon
Location: Portland, Oregon
Coordinates: 45°36′24″N 122°40′51″W / 45.60667°N 122.68083°W / 45.60667; -122.68083Coordinates: 45°36′24″N 122°40′51″W / 45.60667°N 122.68083°W / 45.60667; -122.68083
Built/Founded: 1915
Architect: Harrington,Howard & Ash
Architectural style(s): No Style Listed
Governing body: State
MPS: Historic Bridges/Tunnels in Washington State TR
Added to NRHP: July 16, 1982
NRHP Reference#: 82004205[1]

The Interstate Bridge (also Columbia River Interstate Bridge, I-5 Bridge, Portland-Vancouver Interstate Bridge) is a pair of nearly identical steel vertical lift, through truss bridges that carry Interstate 5 traffic over the Columbia River between Vancouver, Washington, and Portland, Oregon, in the United States. First opened to traffic in 1917 with a second span opening in 1958, the bridge handles 124,500 vehicles (as of 2004).[2] The green structure, which is over 3,500 ft (1,067 m) long, carries traffic over three northbound lanes and three southbound lanes.


First bridge

The bridge was built to replace an overcrowded ferry system operated by Pacific Railway, Light & Power Co. Construction on the bridge began in March 1915, following the sale of bonds.[3] The first bridge was opened on February 14, 1917 at a cost of $1.75 million, which was shared between Clark County and Multnomah County.[4] Clark County paid $500,000 with Multnomah County paying $1,250,000.[5] The first bridge has a total of 13 steel spans with three measuring 275 ft (84 m) in length while the remaining ten spans are 265 ft (81 m) long.[5] One of the 275 ft (84 m) spans is the lift span for allowing river traffic under the bridge.[5] The original paved roadway was 38 ft (11.6 m) wide and had a 5 ft (1.52 m) wide sidewalk.[5] It was the first automobile bridge across the river between Washington and Oregon,[5] and the second to span the river at all, after the Wenatchee Bridge of 1908.[6] It was originally a toll bridge costing 5¢ per person. In 1929 the states of Washington and Oregon jointly purchased it from the counties and subsequently removed the tolls.[6]


In 1958 a $14.5 million upgrade created a southbound span and doubled the capacity of the bridge. The new bridge was built with a "humpback" that provides 72 ft (21.9 m) of vertical clearance and minimizes bridge openings. At the time the new bridge was opened, the old one closed to give it the matching humpback. When both bridges were opened in 1960, tolls were reinstated at $.20 for cars, $.40 for light trucks, and $.60 for heavy trucks and buses, until removed in 1966 after the construction expenses were paid off.[7]

Components of the bridge were manufactured and prepared for assembly in Gary, Indiana.

A $3 million upgrade to the lift cables, expansion joints, and a deck repaving was completed in 1990. The diesel generator used to power the lift was replaced in 1995 at a cost of $150,000. In 1999 the bridge was repainted at a cost of $17 million. A $10.8 million electrical upgrade was completed in mid-May 2005.[8]

The bridge is 3,538 feet (1,078 m) long with a main span of 531 feet (162 m).[9] The vertical lift provides 176 feet (53.6 m) of river clearance when fully opened. Each opening is for ten minutes and does so between 10 and 20 times per month.[10]

The bridge in 1917

Signals for several miles each direction warn of bridge opening since traffic has to stop and wait. Due to this interruption, the Interstate Bridge is one of the Federal Highway Administration's highest priorities for replacement. Commercial river traffic schedules passage to avoid rush hour.

In 2001 the six total lanes of the bridges carried 120,000 vehicles daily including 10,000 trucks. Full traffic capacity occurs four hours every day.[10]


Currently, many traffic engineers consider the bridge to be obsolete, both due to its age and its limited capacity. The bridge is frequently a bottleneck which impacts both traffic on the freeway, as well as on the river. The Oregon and Washington state departments of transportation are jointly studying how to replace the bridge. Initially, the estimated cost for a replacement bridge was around $2 billion,[11] but that number has climbed steadily to around $4.2 billion.[12]

A replacement (especially a fixed span bridge) is complicated by a railroad drawbridge crossing the Columbia a short distance downriver, which constrains the location of the shipping channel; and by approach paths to Portland International Airport in Portland and to Pearson Field in Vancouver, which limit the height of any new structure. Some have proposed replacing the bridge in a different location. There were originally 12 transportation plans that were being studied to improve and expand the Interstate 5 crossing of the Columbia River.[13] In late 2006, 4 of these plans were selected for a final proposal, along with a fifth no-build option.[14] The Columbia River Crossing project's six local partner agencies selected a replacement I-5 bridge and light rail extension to Clark College as the project's Locally Preferred Alternative (LPA) in 2008.[15]

There is also a long standing debate as to whether or not a new bridge would include a MAX Light Rail line, express buses or bus rapid transit. During his 2007 "State of the City" address, Vancouver mayor Royce Pollard stated

I've said it before, but it bears repeating – Vancouver and Clark County residents have the cheapest buy-in to one of the most successful light-rail systems in the world, the MAX system. There is over $5 billion invested in light rail across the river. We can tap into that system at a very minimal cost. We’d be foolish not to. The bi-state Columbia River Crossing initiative is making plans for the future of our community for 50 years and beyond. This project should not happen without integrating light rail that comes into downtown Vancouver. If the final alternative doesn’t have a light rail component, I will not support it.[16]

In December 2007, Oregon Governor Ted Kulongoski advocated for a new bridge, publicly endorsing the Oregon Business Plan's proposal.[17]

In 2008, as fuel prices increased and project cost estimates soared, many in the area began questioning whether the project is worth the costs. In addition, many on the Portland side of the river fear that a 12 lane highway bridge to Vancouver, which has virtually no land use restrictions, will encourage suburban sprawl and development north of the river.[18]

Further concerns over the 12-lane "Columbia River Crossing" (CRC) proposal include its failure to examine critical environmental impacts, such as damage to Clark County's drinking water supply, endangered fish habitat in the Columbia, and air pollution in North Portland.

In 2008, the Environmental Protection Agency found that the Draft Environmental Impact Statement for the CRC had failed to adequately cover these issues, as well as the potential induced demand for suburban sprawl. In a letter to CRC planners, the EPA wrote that "There was no indication (in the CRC environmental impact statement) of how these vulnerable populations might be impacted by air pollution, noise, diesel construction vehicles and increased traffic", referring to minority communities in North Portland.[19]


  1. ^ "National Register Information System". National Register of Historic Places. National Park Service. 2008-04-15.  
  2. ^ "Average Daily Traffic on Oregon’s Interstate Highways 1954–2004" (PDF). Oregon Department of Transportation. May 10, 2006. pp. 2. Retrieved 2007-08-29.  
  3. ^ Holstine, Craig E. (2005). Spanning Washington : Historic Highway Bridges of the Evergreen State. Washington State University Press. pp. 103–104. ISBN 0-87422-281-8.  
  4. ^ Wood, Sharon (2001). The Portland Bridge Book. Oregon Historical Society. ISBN 0-87595-211-9.  
  5. ^ a b c d e Horner, John B. (1919). "Oregon: Her History, Her Great Men, Her Literature". The J.K. Gill Co.: Portland.
  6. ^ a b Dorpat, Paul; Genevieve McCoy (1998). Building Washington: A History of Washington State Public Works. Tartu Publications. pp. 111–112. ISBN 0-9614357-9-8.  
  7. ^ Dylan Rivera (August 9, 2008). "I-5 bridge tolls divide Portland, Vancouver". The Oregonian. Retrieved 2008-08-09.  
  8. ^ "Interstate Bridges Electrical Upgrade". Oregon Department of Transportation. Retrieved 2006-11-05.  
  9. ^ Smith, Dwight A.; Norman, James B.; Dykman, Pieter T. (1989). Historic Highway Bridges of Oregon. Oregon Historical Society Press. p. 209. ISBN 0-87595-205-4.  
  10. ^ a b I-5 Partnership (PDF). Regional Economic Effects of the I-5 Corridor: Columbia River Crossing Transportation Choke Points. Retrieved 2009-03-04.  
  11. ^ Mayer, James (November 22, 2006). "Columbia bridge advice: Scrap the old, build new". The Oregonian.  
  12. ^ Rivera, Dylan (May 28, 2008). "Charge tolls first, then maybe build a bridge, Metro councilors say". The Oregonian.  
  13. ^ "Preliminary Alternative Packages". Columbia River Crossing. Retrieved 2006-11-05.  
  14. ^ Columbia River Crossing: Project Alternatives
  15. ^ Columbia River Crossing: Locally Preferred Alternative
  16. ^ "State of the City". City of Vancouver. January 23, 2007. Retrieved 2007-01-25.  
  17. ^ McCall, William (2007-12-04). "Ore.: Governor urges new bridge". Houston Chronicle (Associated Press).  
  18. ^ "Bridge to Disaster". The Portland Mercury. March 19, 2008.  
  19. ^ "I-5 bridge impacts on pollution, growth unexamined". The Oregonian. July 10, 2008.  

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