do you know else about this department?
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what does interstate 675 (michigan) refers to? It is an auxiliary Interstate Highway in the US state of Michigan. when was it built? Construction of it started in 1969 and the freeway opened in 1971. who is behind the construction? Michigan State Highway Department (MSHD)
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Interstate 675 (Michigan) [SEP] History
I-675 was initially planned in the mid-1950s, and the Michigan State Highway Department (MSHD) originally proposed the number I-275 for the freeway through Saginaw in 1958, while the MSHD proposed an I-73 number for what is now I-275. The state started construction on I-675 in 1969. The freeway was to provide access to the downtown Saginaw area and serve as a bypass for the original Zilwaukee Bridge northeast of downtown, roles that continue today. At the time, the Zilwaukee Bridge was a bascule bridge that could be raised to allow shipping traffic to use the Saginaw River. Opening the drawbridge would back traffic up on the freeway for up to four hours on holiday weekends.