Interstate Bridge - First Bridge

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. The first bridge was opened on February 14, 1917 at a cost of $1.75 million (equivalent to $32 million in 2012), which was shared between Clark County and Multnomah County. Clark County paid $500,000 and Multnomah County $1,250,000.

The first bridge has a total of 13 steel spans, with three measuring 275 feet (84 m) in length and the remaining ten spans 265 ft (81 m) each. One of the 275-foot (84 m) spans is the lift span for allowing river traffic under the bridge. The lift span is capable of moving 136 ft (41 m) vertically, and provides 176 ft (53.6 m) of clearance below when fully raised. The towers are 190 ft (57.9 m) tall, above the roadway.

The original paved roadway was 38 ft (11.6 m) wide and had a 5 ft (1.52 m) wide sidewalk. It was the first automobile bridge across the river between Washington and Oregon, and the second to span the river at all, after the Wenatchee Bridge of 1908. It was originally a toll bridge costing 5¢ per vehicle or per horse and rider, equivalent to $0.91 in 2012. In 1928 the states of Washington and Oregon jointly purchased the bridge from the counties and discontinued tolling the following year.

Electric streetcars operated across the bridge from opening day in 1917 until 1940. The bridge's deck carried dual-gauge track, to accommodate both Vancouver's standard gauge cars and Portland's narrow gauge cars. Before the bridge, Portland had a Vancouver streetcar line since 1893, but it ran only to Hayden Island, where passengers transferred to a ferry owned by the street railway company to continue across the river to Vancouver. Streetcar service across the Interstate Bridge ended on September 3, 1940.