Motorists, expect delays from now until fall on Washington's busiest cross-state highway, I-90.
Construction has resumed along Lake Keechelus in the Cascades, where crews are adding new lanes, building bridges, straightening sharp curves, and repaving. In June, rock blasting resumes on the east shore Mondays through Thursdays, starting one hour before sunset. I-90 closures will last about 60 minutes.
Altogether, I-90 upgrades will span 15 miles of freeway from Hyak to Easton upon completion in fall 2020.
The I-90 corridor always has been critical for transportation and commerce. Dating to the mid-1800s, Snoqualmie Pass has evolved from Indian trail to wagon road to railway route, from to Sunset Highway to U.S. 10 to modern interstate.
In 1909, the Milwaukee Road opened its "high line" rail route from Cedar Falls, near North Bend, up the Cascades to Laconia – now called Snoqualmie Pass – then down to Easton and beyond. (See top two black and white photos.) Milwaukee bypassed Laconia in 1915 when it opened its 2.3-mile Snoqualmie Tunnel, drilled beneath today's ski areas between Hyak and Rockdale.
Rendered obsolete by the tunnel, Milwaukee's high line between Rockdale, Laconia, and Hyak was abandoned, but the two-lane Sunset Highway – an automobile route – literally was built on top of the railroad right of way. The name "Laconia" quickly fell into disuse, supplanted by Snoqualmie Pass.
WSDOT first plowed the highway all winter beginning in 1931, and In 1934 it was paved and became part of U.S. Highway 10. WSDOT built two snowsheds in 1950, one on the west side of the pass at "Airplane Curve" (see color photo) and a shorter one alongside Lake Keechelus. Both have since been demolished. In 1953, much of U.S. 10 was widened to four lanes.
And today, Snoqualmie Pass travelers are witnessing the latest in 100+ years of upgrades to Washington's east-west mainline.
Photos courtesy WSDOT, Washington State Historical Society, and MOHAI