Associated Press

LANSING — Michigan has identified rural highways where the speed limit will rise to 75 m.p.h. as soon as next week.

The state on Wednesday announced 600 miles where the limits will increase from 70 m.p.h. to 75 m.p.h., and 900 miles where they will go from 55 m.p.h. to 65 m.p.h.

The first freeways to see 75 m.p.h. limits by mid-May will be I-75 between Bay City and Sault Ste. Marie, stretches of U.S. 127 between the Lansing and Grayling areas, and U.S. 131 between the Grand Rapids and Cadillac areas. The Michigan Department of Transportation also will begin installing new 65 m.p.h. limit signs for trucks and buses.

Related:See all freeway route speed limit increases by clicking here(PDF)

State legislators last year passed a law instructing MDOT and Michigan State Police to consider increasing speeds on freeways and highways across the state.

"The corridors identified by MDOT and MSP were selected not only because studies indicated most drivers were already driving at those increased speeds, but also because their design and safety features were best suited to these speed limits," State Transportation Director Kirk T. Steudle said in a news release. "We reviewed design speeds, crash patterns, number of access points, traffic volumes and continuity of these corridors, and chose them to minimize necessary improvements for higher speed limits."

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"The engineering and safety studies conducted utilized the 85th-percentile speed, which is a national scientifically proven method to determine and establish safe speed limits," Col. Kriste Kibbey Etue, director of the MSP, said in the release.

Officials expect to finish installing all new signage by November.

Here's a list of affected roadways, according to MDOT:

Freeway routes:

• I-75 – Bay City to US-23 in Mackinaw City (Bay, Arenac, Ogemaw, Roscommon, Crawford, Otsego, Cheboygan, and Emmet counties), and St. Ignace to Sault Ste. Marie (Mackinac and Chippewa counties)

• US-127 – I-69 to the end of the freeway at St. Johns (Clinton County), and the beginning of the freeway at Ithaca to I-75 (Gratiot, Isabella, Clare, Roscommon, and Crawford counties)

• US-131 – M-57 to the end of the freeway north of Manton (Kent, Montcalm, Mecosta, Osceola, and Wexford counties)

Limited access freeways:

• I-69 – I-69 Business Route (Saginaw Highway) to Swartz Creek (Clinton, Shiawassee, and Genesee counties)

• I-69 – From the Genesee/Lapeer county line to I-94 (Genesee, Lapeer, and St. Clair counties)

• US-10 – M-115 to I-75 (Clare, Isabella, Midland, and Bay counties)

• US-31 – South Oceana County line to US-10 (Oceana and Mason counties)

Non-freeways:

• US-2 – Wakefield to Iron River (Gogebic and Iron counties)

• US-2 – St. Ignace to Rapid River (Mackinac, Schoolcraft, and Delta counties)

• US-23 – East of Cheboygan to east of M-65 (Cheboygan and Presque Isle counties)

• US-45 – North of US-2 to M-26 (Gogebic and Ontonagon counties)

• M-28 – East of Harvey to Christmas (Marquette and Alger counties)

• M-28 – Munising to I-75 (Alger, Schoolcraft, Luce, and Chippewa counties)

• M-28 – Wakefield to US-41 (Gogebic, Ontonagon, Houghton, and Baraga counties)

• M-32 – Atlanta to Alpena (Montmorency and Alpena counties)

• M-33 – Atlanta to Onaway (Montmorency and Presque Isle counties)

• M-37 – Mesick to Wolf Lake (Wexford and Lake counties)

• M-55 – US-31 to Cadillac West (Manistee and Wexford counties)

• M-64 – M-28 to Old M-107 (Ontonagon County)

• M-65 – US-23 to M-32 west junction (Arenac, Iosco, Alcona, and Alpena counties)

• M-65 – M-32 east junction to US-23 (Alpena and Presque Isle counties)

• M-68 – I-75 to US-23 (Cheboygan and Presque Isle counties)

• M-72 – Grayling to Mio (Crawford and Oscoda counties)

• M-72 – Fairview to M-65 north junction (Oscoda and Alcona counties)

• M-72 – M-65 south junction to Harrisville (Alcona County)

• M-77 – US-2 to M-28 (Schoolcraft County)

• M-115 – Benzonia to Mesick (Benzie and Wexford counties)

• M-123 – I-75 to Paradise (Mackinac and Chippewa counties)

• M-231 – M-45 to M-104 (Ottawa County)

Christopher Haxel contributed to this report.

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