Le Mars’ proposal for modifying the southern part of Business US 75 from a four-lane urban arterial is not something I think has been tried in Iowa. Here’s the plan, from the Le Mars Sentinel:
The proposal would transform the northbound exterior lane into one dedicated to through and right-turn traffic. The northbound interior lane would be dedicated to left turns only. The southbound exterior lane would would be dedicated to right turns only. The southbound interior lane would be dedicated to southbound through traffic and left turns only.
Below is a diagram of what that looks like in street-arrow form. Its asymmetric nature likely springs from the fact that most of that part of Business 75 parallels railroad tracks, cutting the frequency of southbound left turns.
The same Sentinel story also notes that much more of the southern part of Business 75 will have its speed limit cut from 45 to 35 mph. The southern part of the business route is entirely under Le Mars’ jurisdiction now; north of IA 3, it is secret IA 404.
P.S. As of last week, there have been no signage changes on the bypass; the BGSs still list streets instead of “Le Mars,” as the city petitioned the DOT shortly after new 75 opened.
