BNSF Rebuilds One Bridge, Begins Another in the NorthwestWritten by Bruce E. Kelly, Railway Age
Progress is well under way on structural upgrades to BNSF’s 119-year-old Bridge 3.9A over Lake Pend Oreille outside Sandpoint, Idaho. The completion in November 2022 of the adjacent 4,873-foot long Bridge 3.9B allowed BNSF to divert all traffic off of the older bridge and resume its renovations that began more than a decade ago.
During 2008-09, new piers and deck spans were installed at both ends of the 1904 bridge. The work currently under way is finishing that process across the bridge’s mid-section. By the end of April 2023, pre-cast concrete caps were being placed on top of replacement piers near the middle of Bridge 3.9A. BNSF’s “old bridge” over Lake Pend Oreille will be a virtually new one when it re-enters service in late summer 2023.
No specific timeline has been given for the next phase of BNSF construction at Sandpoint, which will include new dual crossovers being built northwest (railroad east) of the two big bridges, and a mile of second main track from the crossovers onward into Sandpoint. This new track will run past the historic Sandpoint depot to Sandpoint Jct., where BNSF’s Northern Corridor connects with what has been Montana Rail Link and will soon become BNSF’s MRL Subdivision.
Meanwhile, some 58 miles west of Sandpoint, initial work has begun for a second bridge over the Spokane River near Irvin, Wash. Preliminary grading was performed in 2020 for the approaches to the new bridge, which will eventually allow BNSF to install the last segment of second main track—between Irvin and Otis Orchards—to fully doubletrack its busy Spokane-Sandpoint corridor, which some refer to as “The Funnel.”
BNSF’s plans for a second Spokane River bridge officially emerged in 2004 and received environmental approval in 2006. At that time, the new bridge was part of a proposed regional concept known as Bridging the Valley (BTV), organized by local communities in cooperation with BNSF and Union Pacific (UP). BTV’s goal was to eliminate as many at-grade road/rail crossings as possible and replace them with bridges, in an area that is rapidly transitioning from rural into residential and commercial. Several of those bridges have already been built on both BNSF and UP, with more to follow.
The most ambitious aspect of BTV called for the construction of a second main track—and even a third main track where necessary—to accommodate UP trains on the BNSF right-of-way between the Spokane Valley and Athol, Idaho. This was to be followed by the removal or downgrading to branch line status of UP’s main track between those points. Support for this joint BNSF/UP corridor ultimately dissolved, and UP continues using its existing line through the area.
In January, BNSF announced construction of the new Spokane River bridge and its associated second main track as part of its 2023 capital investments, but no details regarding the bridge’s cost, specifications, or projected completion date have been made public by BNSF. The existing 544-foot long Spokane River bridge that’s currently used by BNSF was completed in 1911 by Northern Pacific, replacing a previous bridge built in 1881.