Interstate 39 in Wisconsin

Interstate 39 Main route of the Interstate Highway System
Maintained by WisDOT
Length:	182 mi[1] (292.90 km)
Formed:	October 22, 1993
South end:	I-39 at the Illinois state line
Major junctions:	I-90 , near Beloit US 12 / US 18 in Madison I-94 in Madison US 151 in Madison US 51 near Portage US 10 in Stevens Point
North end:	WIS 29 in Wausau
Wisconsin highways < WIS 38 WIS 39 > County - Bannered - Rustic

Welcome sign

In the U.S. state of Wisconsin, Interstate 39 is an Interstate-standard^{[citation needed]} freeway that runs north from the Illinois border near Beloit to just south of Wausau. This is a distance of 182 mi (293 km). With the exception of an eight-mile (13 km) segment around Portage, the Interstate shares a route with at least one other route number. From Illinois to Portage, I-39 is concurrent with I-90. I-94 joins the pair in Madison until Portage. From Portage northward, US 51 is co-signed with the interstate. At 29 miles (47 km) in length, this concurrency of three Interstates is the longest in the country.

Route description

Beloit to Portage

I-39 enters from Illinois along with I-90, passing under Stateline road, and bypasses Beloit to the east, meeting I-43 and WIS 81, both of which terminate at this interchange. Including WIS-81, two interchanges provide access to Beloit. The Interstates continue due north and are joined by WIS 11 seven miles (11 km) north of the I-43 interchange as the route bypasses Janesville around the east and north. WIS 11 leaves the freeway two miles further north. US 14 and WIS 26 interchange with the freeway on the northeast side of Janesville. WIS 59 east of Edgerton. The highway then enters Dane County.^[2]

US 51 joins the I-39/I-90 at the southern terminus of WIS 73 north of Edgerton, and leaves four miles (6 km) north, seven miles (11 km) east of Stoughton. The Interstate gradually turns westward around Utica to an interchange with CTH N. It then turns gradually back to the north and interchanges with US 12 and US 18 in Madison. I-39 and I-90 bypass Madison to the east, and I-94 joins the concurrency at the eastern terminus of WIS 30, an interchange known as the Badger Interchange^[3]. The Interstate next crosses US 151 two miles (3 km) further north, which includes a south-side access to High Crossing Boulevard. The last two Madison area interchanges are US 51 three miles (5 km) northwest of the US 151 interchange and WIS 19 another mile northwest of the US 51 interchange. Access is provided to CTH V just west of DeForest four miles (6 km) further north. I-39/I-90/I-94 enter Columbia County four miles (6 km) north-northwest of CTH V.^[4]

The Interstates cross WIS 60 at an interchange three miles (5 km) north of the county line west of Arlington and CTH CS at another interchange four miles (6 km) further north near Poynette. The highway crosses the Wisconsin River four miles (6 km) north of CTH CS. At three miles (5 km) further along the route from the river, I-39 leaves the concurrency with I-90 and I-94 and turns northward while the other two interstates turn northwest. WIS 78 terminates at this interchange and heads southwest. This is the starting point of the segment of freeway that carries the I-39 route alone. The interstate crosses WIS 33, the first of three interchanges accessing Portage, two miles (3 km) north of I-90/I-94. After crossing the Wisconsin River again, I-39 crosses the second interchange - this one with WIS 16 and turns northeast to an interchange with US 51. The US route joins the Interstate and both turn north once again and leave the Portage area and, after four miles (6 km), enter Marquette County.^[5]

Portage to Wausau

Interstate 39, along with U.S. 51, in northern Wisconsin

WIS 23 joins I-39/US 51 northbound after four miles (6 km) from the county line. The three highway pass along Buffalo Lake and encounter a south-side half interchange with CTH D in the town of Packwaukee. WIS 23 leave the concurrency to the east at WIS 82 near Oxford. and the freeway takes a due north route to pass Westfield. I-39/US 51 enters Waushara County six miles (10 km) north of Westfield.^[6] Four miles north of the county line, I-39 / US 51 junction with WIS 21 in Coloma. I-39/US 51 meet an interchange in Hancock with CTH V five miles (8 km) further north and WIS 73 crosses in Plainfield after another five miles (8 km). This is two miles (3 km) south of the Portage County line.^[7]

In Portage County, I-39/US 51 takes a straight due north trajectory which provides access to CTH D, CTH W and WIS 54 (also Business U.S. 51) over twelve miles (19 km). The WIS 54 interchange and the CTH B interchange a mile and a half north of it provide access for Plover. The next four interchanges - CTH HH, US 10 Eastbound / WIS 66 Westbound, Stanley Street and Business US 51 provide access to Stevens Point. Amongst these interchanges, the freeway turns northwestward, bypassing the city to the east and north. I-39/US 51 cross two more interchanges while in Portage County: Casimir Road four miles (6 km) northwest of Stevens Point^[8], and Westbound US 10 two miles (3 km) north of Casimir Road. The freeway then parallels the Wiconsin River for six miles (10 km) to an Interchange with CTH DB east of Lake DuBay and one mile (1.6 km) south of the Marathon County line.^[9]

WIS 34 terminates at an interchange with I-39/US 51 in Knowlton three miles (5 km) northwest of the freeway's entry into Marathon County. The freeway turns due north from this interchange. WIS 153 crosses the freeway four miles further north in Mosinee. Maple Ridge Road crosses after another two miles (3 km) as the freeway turns northeastward into Rothschild.^[10] An interchange with Business US 51 is just south of the Wisconsin River crossing after four miles (6 km) from Maple Ridge Road. I-39 ends two miles (3 km) further north at the interchange with WIS 29 East just southwest of Wausau.^[11]

History

I-39 became reality in Wisconsin with the announcement of the stretch between Portage and Wausau in 1996 by then Governor Tommy Thompson. This came after a five-year push to get the interstate designation approved^[12] The route was officially designated in 1992. The remaining segment along I-90/I-94 was not signed for I-39 until late 1998^[13] The section between the I-90/I-94 interchange and US 51's interchange in Portage was previously a part of WIS 78. That route was truncated back to its current terminus when the Interstate's designation went into effect.^[14] The designation of I-39 violated Wisconsin's rule of not having any state trunkline number duplicated - whether it be Interstate, U.S. or state, as WIS 39 already existed.^[13]

Future

Speculation exists that Interstate 39 could be extended north from Wausau to Merrill, Wisconsin along the U.S. Route 51 freeway, which is nearly Interstate standard, but is not part of the Interstate system as of August 2006. An Interstate designation on this portion of freeway cannot be pursued until underheight overpasses in the Wausau area have been raised and other modifications made. Some of these modifications are being made as part of a long-term improvement project on US-51 which will not be completed until 2010. WisDOT sources have only indicated plans exist to potentially extend I-39 northerly to the northern junction with STH-29 once that interchange has been reconstructed.^[15]

Exit list

Beloit to Portage

See Interstate 90 in Wisconsin from exits 185B-108B.

Portage to Wausau

County	Location	Mile[16]	#[17]	Destinations	Notes
Columbia	Portage	79.14	84B	I-90 / I-94 – Madison, Wis Dells	I-39 South follow I-90 East / I-94 East
		79.35	84A	WIS 78 – Merrimac
		79.68	85	Cascade Mt Rd
		81.41	87	WIS 33 – Portage, Baraboo
		83.88	89A	WIS 16 east – Portage	Northbound
		84.13	89B	WIS 16 west to WIS 127 – Wis Dells
		84.13	89B-A	WIS 16 to WIS 127 – Portage, Wis Dells	Southbound
		85.51	92	US 51 south – Portage	US 51 North follow I-39 North
Marquette	Endeavour	94.12	100	WIS 23 west / CTH P – Wis Dells, Endeavor	WIS 23 East follow I-39 / US 51 North
	Packwaukee	98.33	104	CTH D – Packwaukee	Northbound exit; Southbound entrance only
	Montello	100.36	106	WIS 23 east / WIS 82 west – Oxford, Montello	WIS 23 West follow I-39 / US 51 South
	Westfield	106.96	113	CTH E / CTH J – Westfield
Waushara	Coloma	117.92	124	WIS 21 – Coloma, Necedah
	Hancock	125.09	131	CTH V – Hancock
	Plainfield	130.64	136	WIS 73 – Plainfield, Wis Rapids
Portage	Almond	133.78	139	CTH D – Almond
	Bancroft	137.26	143	CTH W – Bancroft, Wis Rapids
	Plover	145.63	151	WIS 54 / US 51 Bus. – Wis Rapids, Plover	Waupaca use Exit 151
		147.27	153	CTH B – Wis Rapids, Plover	Amherst use Exit 153
	Whiting	150.20	156	CTH HH – Whiting
	Stevens Point	152.27	158A	US 10 east – Waupaca, Appleton	Northbound
		152.34	158B	WIS 66 west – Wisconsin Rapids, Stevens Point
		152.43	158	US 10 east / WIS 66 west – Stevens Point, Waupaca	Southbound Appleton use exit 158
		153.66	159	WIS 66 east – Stevens Point, Rosholt	Stanley St use Exit 159
		155.79	161	US 51 Bus. – Stevens Point
	Hull	157.54	163	Casimir Rd
		159.22	165	US 10 west – Marshfield
	Lake Dubay	165.03	171	CTH DB – Knowlton, Lake DuBay	Southbound omits Knowlton
Marathon	Knowlton	169.31	175	WIS 34 – Knowlton, Wis Rapids	Northbound omits Wis Rapids
	Mosinee	173.29	179	WIS 153 – Mosinee, Elderon
	Kronenwetter	175.15	181	Kronenwetter, Mosinee	Maple Ridge Rd use Exit 181
	Rothschild	179.21	185	US 51 Bus. – Rothschild, Kronenwetter	Northbound: Schofield use Exit 185 Southbound signed Rothschild, Schofield
	Rib Mountain	181.38	187	WIS 29 east – Weston, Green Bay	End of I-39 WIS 29 West follow US 51 North

References

Interstate 39
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