Interstate 470 Colorado

Interstate 470 Colorado
History
East End
West End
C-470 north at Ken Caryl Ranch, CO

Travelers on C-470 north catch a glimpse of Red Rocks beyond the cut SH 8 takes between Mount Glennon and Dinosaur Ridge. The freeway runs along the Hog Back north from Ken Caryl Ranch to Golden. 08/11/14

Overview

Colorado 470 (C-470) follows the planned loop of Interstate 470 around the Denver metropolitan area south from I-70 at Golden and east to Littleton, Centennial and I-25 in Lone Tree. The commuter freeway serves an array of suburban development and Chatfield State Park.

C-470 Express Lanes

Started in 2016, construction underway through 2020 expands 12.5 miles of C-470 east from SH 121 (Wadsworth Boulevard) at Ken Caryl to Interstate 25 at Lone Tree. The $276 million project adds two managed lanes westbound from I-25 to Colorado Boulevard, and a single express lane from Colorado Boulevard to SH 121. One express lane is also being added eastbound from Wadsworth Boulevard to I-25. Work also adds auxiliary lanes, improves the ramp geometry at several interchanges and adds ramp metering where needed. Bid opening for the project took place on March 30, 2016.

History

C-470, which forms the southwestern quadrant of the Denver Beltway system, was adopted in 1969 by the Denver Metropolitan Area Transportation Study. Interstate 470 was added to the Interstate Highway System under the Federal Highway Act in December 1968.1 The route went through various studies through 1972, when the final environmental impact statement was released and submitted to the Federal Highway Administration (FHWA).

As was the case with several Interstate Highways studied in the early 1970s, the environmental impact statement brought controversy. Governor Dick Lamm, who was elected on a platform that included the elimination of Interstate 470 from Denver metropolitan area transportation plans, created the Interstate 470 Ad Hoc Commission. The commission studied the route and conducted public sessions. In December 1976, the commission recommended that I-470 should be withdrawn from the Interstate Highway System and an at-grade parkway (Centennial Parkway) be constructed in its place.1 Shortly thereafter, the Colorado Department of Highways concurred with the findings of the commission. On June 23, 1977, the FHWA approved eliminating Interstate 470.1

Route Information

  • East End – Lone Tree, CO

  • West End – Golden, CO

  • Mileage – 28.162*

  • Cities – Golden, Lakewood, Littleton, Centennial, Lone Tree

  • JunctionsI-70 I-25

Source: * – 26.195 miles for Route 470A and 1.212 miles for Route 470W.
Colorado Department of Transportation Straight Line Diagram Tool

C-470 at Soda Lakes, CO
Looking north from C-470 at the Soda Lakes toward the Hutchinson Green Mountain Village and Rooney Valley (Solterra) developments against Green Mountain. 08/11/16

One of the key points made by Colorado Governor Dick Lamm in opposition to Interstate 470 was that the freeway would be the catalyst for suburban sprawl. Despite being built with just four lanes, Centennial Parkway ultimately fueled the suburban boon in Jefferson County and Lakewood.

Denver, CO - 1975
1975 Gousha Map of Denver showing proposed Interstate 470.

Funds previously allocated for I-470 were earmarked not only to the Centennial Parkway corridor, but also to improvements on U.S. 85 (Santa Fe Drive) and other transportation improvements throughout the region. Construction got underway for Centennial Parkway in 1982, as Colorado 470. Design changes made by that time included interchanges in place of signalized intersections.

Referred to as C-470, Centennial Parkway opened in stages with the last section completed in October 1990. While Colorado 470 is a freeway, there are right in right out (RIRO) connections along westbound at Colorado 75 (Columbine Hills) and Hampden Avenue (Bear Creek Lake Park).

Starting in the 1990s and continuing through the 2000s, the Denver Beltway was extended east to Aurora and north to Broomfield as a toll road via Extension 470 (“E-470”) and the Northwest Parkway. These sections were never considered for inclusion in Interstate 470.

Highway Guides

East End I-25 E-470 Toll Road – Lone Tree, Colorado

I-25 north at C-470

I-25 north at C-470 - Lone Tree, CO

Interstate 25 heads north between Lone Tree and Meridian one mile from Lincoln Avenue to Exit 194 for C-470 west and E-470 north. 04/28/17

I-25 north at C-470 - Meridian, CO

A pedestrian bridge for the RTD Lincoln Station spans I-25 a quarter mile south of the four level interchange with C-470/E-470. 04/28/17

I-25 north at C-470 - Meridian, CO

Two lanes depart from I-25 north at Exit 194 for C-470 west to Littleton, Lakewood and Golden and the E-470 toll road north to Parker, Aurora and Denver International Airport (DEN). 04/28/17

I-25 north at C-470 - Meridian, CO

A single lane flyover leads west onto the general travel lanes for C-470 ahead of Quebec Street to Centennial and Lone Tree and the C-470 Express Lanes toward Littleton. 04/28/17

West End I-70 U.S. 6 – Golden, Colorado

C-470 west at I-70

C-470 west at I-70 - Lakewood, CO

C-470 travels 1.5 miles north from Alameda Parkway and Rooney Valley to Interstate 70 at Exit 1. 08/11/16

C-470 west at I-70 - Lakewood, CO

Three lanes rise along the west slopes of Green Mountain to Interstate 70 west to Genesee Park and Grand Junction and east to Wheat Ridge and Denver. 08/11/16

C-470 west at I-70 - Golden, CO

The C-470 mainline extends north to U.S. 6 (6th Avenue) and Johnson Road in Golden while two lanes part ways for I-70 (Exit 1). 08/11/16

C-470 west at I-70 - Golden, CO

Commuters headed to Downtown Denver join I-70 east just ahead of the 6th Avenue freeway for U.S. 6 east. I-70 west continues west through the Jefferson County suburbs to the Summit County line and Idaho Springs. 08/11/14

Throwback – C-470 west at I-70

C-470 west at I-70 - 2004

Completion of the Alameda Parkway interchange (Exit 2) in July 2008 included a new acceleration lane for C-470 west in place of the one-mile overhead for Interstate 70. 09/01/04

C-470 west at I-70 - 2004

The former mainline of C-470 was converted into a collector distributor roadway for Exit 1by 2006. Traffic for U.S. 6 and I-70 now splits a half mile beyond this monotube assembly. 09/01/04

C-470 west at I-70 - 2004

Control cities for Interstate 70 remain the long distance destination of Grand Junction and nearby Denver with sign replacements. 09/01/04

C-470 west at I-70 - 2004

A single lane continued beyond the loop ramp for I-70 west to the C-470 ramps for U.S. 6. 09/01/04

C-470 west at I-70 - 2004

South Table Mountain rises to the north as C-470 concludes with an at-grade ramp to U.S. 6 (6th Street) east and a flyover for U.S. 6 west toward Clear Creek Canyon. 09/01/04

Sources:

  1. The Story of I-470, C-470, E-470, W-470, and the Northwest Parkway (Matthew Salek). http://www.mesalek.com/colo/denvers470.html

Page updated February 3, 2020.