According to the 1915 “Report on Detroit Street Railway Traffic and Proposed Subway” (Barclay, Parsons & Klapp), the Woodward lines saw significantly increased utilization between 1904 (12,990,027 passengers) and 1914 (47,457,294 passengers).
Downtown, where all the routes terminated, impeded efficient movement of people in and out of the city. Therefore, their report proposed a series of rerouting of lines as well as a Woodward Avenue subway system.
DETROITography 
According to the 1915 “Report on Detroit Street Railway Traffic and Proposed Subway”, Woodward Avenue trolley lines (streetcar and interurban) saw significantly increasing utilization, between 1904 (12,990,027 passengers), and 1914 (47,457,294 passengers).
Downtown, where all the routes terminated, impeded efficient movement of people in and out of the city. There were times when downtown Detroit streets became gridlocked with streetcars and interurban trolleys.
The century-old report proposed rerouting several surface lines, along with grade-separation of the crosstown and Woodward Avenue lines, via a new Woodward Avenue Subway.
In the end, the proposal was defeated (by one vote) during a meeting of Detroit’s Common Council (the predecessor of today’s City Council). Local hatred of the Detroit United Railway (DUR) traction monopoly was too strong.
In 1922, the City of Detroit purchased DUR lines within the city limits for c. $20 million, and assigned them to Detroit’s new Department of Street Railways (DSR). Privately-held DUR went bankrupt in March 1925.
The rest is history.
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