Capitol Memorial Bridge Built 1931

Capitol Memorial BridgeMorrison Knudsen Foundation
Harry W. Morrison Foundation


The Oregon Trail Memorial Bridge was dedicated on September 15, 1931. The span pays homage to Oregon Trail pioneers who crossed the Boise River at this spot (near Boise State University at Capitol Boulevard) on their way west.

In the 1920s, city leaders envisioned the bridge as a key part of the grand axis connecting the Capitol Building and the Boise Depot. Getting the bridge built took some time, however. Voters failed to pass a construction bond in 1927. Federal WPA relief dollars paid for its completion in 1931. One hundred men employed by Morrison-Knudsen [1] worked 16-hour days for 200 straight days to build the bridge before high-water season, according to the Idaho Heritage Trust.

The Art Deco design included bronze plaques and ceramic tiles made by Works Progress Administration artists. The tiles, in warm, muted tones typical of the era, picture pioneer wagons and Western landscapes. At its completion, the new bridge was described by the Idaho Statesman  in glowing terms: a "masterful work of art" with "glistening white concrete sides that reflect the sun's rays."

To celebrate Boise’s sesquicentennial celebration, Boise City Department of Public Works, the Ada County Highway District, and the Idaho Heritage Trust collaborated to renovate the bridge and restore some of its earlier appeal.

The makeover included tile and bronze repairs, new paint and light fixtures, and restoration of the bridge’s original light poles. After a 50-year period during which the bridge lights had not shown on the water below, they did so once again, a welcome glow to celebrate the city’s 150th birthday. 

Source: Anna Webb, 150 Boise Icons To Celebrate the City’s Sesquicentennial, published by the Idaho Statesman. 

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