Colorado State Highway 470

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State Highway 470 marker

State Highway 470
Map of north central Colorado with SH 470 highlighted in red
Route information
Maintained by CDOT
Length: 27.41 mi[1] (44.11 km)
Major junctions
West end: US 6 in Golden
East end: I-25 / US 87 / E-470 in Lone Tree
Counties: Jefferson, Arapahoe, Douglas
Highway system
Colorado State Highways
US 450 E-470

State Highway 470 (C-470, SH 470) is the southwestern portion of the Denver Metro area's beltway. Originally planned as Interstate 470 in the 1960s, the beltway project was attacked on environmental impact grounds and the interstate beltway was never built. The portion of "Interstate 470" that was built as a state highway is the present-day SH 470, which is a freeway for its entire length.

Route description[edit]

SH 470 begins in Golden, Colorado, starting south from its western terminus at US 6 (6th Avenue) near the intersection with Johnson Road. The highway has interchanges with Interstate 70, State Highway 8, and U.S. Highway 285, then curves to the east. The eastbound portion of SH 470 has interchanges with State Highway 121 (Wadsworth Boulevard), State Highway 75 (Platte Canyon Road), U.S. Highway 85 (South Santa Fe Drive), and State Highway 177 (South University Boulevard). The eastern terminus is the interchange with I-25. Beyond the eastern terminus, the direct continuation of SH 470 becomes the E-470 tollway.


Proposed I-470[edit]

Interstate 470
Location: Golden-Lone Tree

In the 1960s the Colorado Department of Transportation perceived a need for a beltway around the Denver Metro Area and sent a proposal to the Federal Highway Administration. The plan was for the federal government to provide 90% of funds for the project with the state providing the difference. I-470 was added to the Federal Highway Act of 1968 and was to be part of the Interstate Highway and Defense System. The Denver City Council approved the location and began engineering and environmental impact studies. After a few months the studies went under analysis with negative feedback. The Colorado Department of Health was opposed to the interstate beltway on the grounds that it would violate the Federal Clean Air Act. Other studies compared the proposed I-470 to the I-25 and I-225 freeways suggesting that alternate uses for the land (other than freeways) would be more environmentally friendly.

I-470 to Centennial Parkway[edit]

The feedback from the Colorado Department of Health caused all efforts to plan and build the beltway to cease by order of the governor. A separate commission was established by Governor Richard Lamm to evaluate the right course of action. The commission came up with 11 alternatives. The final decision was to use federal highway funds to build a grand parkway known as Centennial Parkway (a partial beltway in the southwest portion of the metro area) and widen existing roads.

Centennial Parkway to SH 470[edit]

As the southwestern area grew rapidly, plans for Centennial Parkway evolved to conform to freeway standards. The proposed road was designated State Highway 470. Present-day SH 470 is a freeway that is mostly built to interstate standards.

Tollways are planned for the rest of the beltway[edit]

After the completion of SH 470 in the southwest, desires for a full beltway persisted in some circles and plans for an extension were created. CDOT did not wish to participate in the building of the freeway extension and left the counties and cities of the metro area to provide funding for the project. The east, north, and northwest portions of the beltway could only be built as tollways.


A tollway extension of SH 470, east and north of the SH 470 eastern terminus, was built to the junction with State Highway 83 (Parker Road) and termed Eastern/Extension 470 or E-470. Subsequently, E-470 was extended to the interchange with I-70 in the east, and later to I-25 in the north. This newly added tollway was built and continues to be administered by a quasi-governmental organization known as the E-470 Public Highway Authority.

Northwest Parkway[edit]

When highway interests pushed for the rest of the beltway to be completed, the city of Golden voted to stop all efforts to finish the beltway due to traffic concerns. The city and county of Broomfield, Colorado effected an 11-mile (18 km) continuation of the E-470 tollway from I-25 to an interchange with US 36 (the former Denver-Boulder Turnpike) near Flatiron Crossing Mall. This section of the tollway is known as the Northwest Parkway, and is administered, similarly to E-470, by its own quasi-governmental agency. In combination with E-470 (47 miles) and SH 470 (27 miles), the Northwest Parkway brings the total length of the completed portion of the beltway around the Denver-Aurora Metropolitan Area to approximately 85 miles (137 km). The uncompleted portion, from the west end of the Northwest Parkway to the northwest end of SH 470, is 19 miles (31 km) along existing streets.[1]

In 2007, the Portuguese company BRISA paid $603 million to operate the road for the following 99 years[2][3] The lease included a clause restricting a "Competing Transportation Facility. This clause was invoked in an April 30, 2008 letter when Broomfield wished to make changes to 160th Ave.

Proposed W-470[edit]

As of August 2003, CDOT made a compromise with the cities of Westminster, Arvada and Golden to do an environmental impact study, the first step in an attempt to complete the beltway by 2020. The last segment of the beltway would be another tollway, tentatively called W-470, and would connect the west end of the Northwest Parkway to the northwest end of SH 470.

Jefferson Parkway[edit]

The Jefferson Parkway is the planned extension to the beltway to begin at the Northwest Parkway and end at SH 93. It is currently in its planning phase. Jefferson County, Broomfield and Arvada have formed the Jefferson Parkway Public Highway Authority to construct the highway. If the 20-mile parkway is constructed, Denver will be completely encircled by a "metropolitan beltway."[4]

Exit list[edit]

All exits are unnumbered.

County Location mi[5] km Destinations Notes
Jefferson Golden 0.000 0.000 US 6 (6th Avenue) Westbound exit and eastbound entrance; west end of SH 470
0.001 0.0016 I-70 west – Grand Junction I-70 exit 260.
0.001 0.0016 I-70 east – Denver Westbound exit and eastbound entrance. I-70 exit 260.
1.842 2.964 SH 26 (Alameda Parkway)
Morrison 4.248 6.836 SH 8 (Morrison Road) Single-point urban interchange
Lakewood Hampden Avenue Westbound exit and entrance
5.699 9.172 US 285 – Fairplay, Denver Cloverleaf interchange
6.250 10.058 Quincy Avenue/Belleview Avenue
7.901 12.715 Bowles Avenue
Ken Caryl 10.192 16.402 Ken Caryl Avenue
12.449 20.035 Kipling Parkway
13.902 22.373 SH 121 (Wadsworth Boulevard)
Littleton 15.443 24.853 SH 75 north (Platte Canyon Road) Westbound exit and entrance
Douglas Highlands Ranch 17.000 27.359 US 85 (Santa Fe Drive)
18.458 29.705 Lucent Boulevard
19.599 31.542 Broadway
21.069 33.907 SH 177 (University Boulevard)
Highlands RanchLone Tree line 24.144 38.856 Quebec Street
Lone Tree 25.574 41.157 Yosemite Street Eastbound exit and westbound entrance
26.195 42.157 I-25 / E-470 – Colorado Springs, Denver East end of SH 470; continues east as E-470, exit 1A. I-25 exit 194.
1.000 mi = 1.609 km; 1.000 km = 0.621 mi


The completion of the road has been mired in controversy. In 1975 Colorado Governor Dick Lamm vowed to "drive a silver spike" through the plans for the road.[6] In 1989 voters turned down an expansion of the road by a four-to-one margin. In the late 1990s a citizens group called Citizens Involved in the Northwest Quadrant (CINQ) was formed to oppose the completion of the road. In 2008, a group of Arvada residents sued to try and stop the city from joining the newly formed JPPHA.[7]

The completion of the road continues to have a primary proponent in the city of Arvada and the city of Broomfield who feel, among other things, it will financially benefit them. A number of localities, including the Town of Superior, the city of Wheat Ridge, and the city of Golden have fought the completion of the road citing, among other things, a decrease in their quality of life.

See also[edit]


  1. ^ "Segment list for SH 470". Retrieved 2007-05-12. 
  2. ^ "Plans to Complete Beltway". Broomfield Enterprise. July 24, 2008. 
  3. ^ Lewis, Al (September 2, 2007). "Parkway Lease Fool's Gambit". Denver Post. 
  4. ^ "Jefferson Parkway Public Highway Authority". Jefferson Parkway Public Highway Authority. Retrieved 21 August 2014. 
  5. ^ Colorado Department of Transportation, Highway Data Archived 2007-10-08 at the Wayback Machine., accessed December 2007: note that not every interval between mileposts is exactly a mile, explaining why more exits than expected are at the exact milepost
  6. ^ Steers, Stuart (June 19, 1997). "The Blacktop Jungle". Westword. 
  7. ^ Flynn, Kevin (2008-06-14). "Arvada clears beltway hurdle". Rocky Mountain News. 

External links[edit]

Route map: Google

KML is from Wikidata