That's not the overall capacity choke. The capacity choke currently is the intersection of Beatty and Dunsmuir. When they first built the viaducts there was 4 through lanes, 2 right turn lanes, and no left turn lanes due to Beatty being one way. Now it's one de-facto left turn lane, one through lane, and one right turn lane.
Beatty didn't become a one-way street until.. mid 80s?
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