Colorado State Highway 470


State Highway 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. The route has previously been called the Centennial Freeway.

Route description

SH 470 begins in Golden as an extension of Johnson Road at an intersection with US 6 near the Jefferson County government office complex and its adjacent light rail station. The interchange also includes direct ramps to westbound US 6, which continues northwest towards central Golden and east to Denver. SH 470 travels south from the intersection on a four-lane freeway and passes over US 40 before reaching an interchange with I-70 near Tin Cup Hogback Park. The freeway expands to six lanes and continues south along the side of Green Mountain on the western outskirts of Lakewood. It intersects SH 8 at a single-point urban interchange in Morrison near the Bandimere Speedway complex.
From Morrison, SH 470 begins a gradual turn to the southeast as it passes between Mount Glennon and Bear Creek Lake Regional Park. It intersects US 285, a minor freeway that travels east through Lakewood, and continues south with four lanes along the edge of a hogback at the edge of the Denver area's suburban sprawl, served by several exits on the freeway. SH 470 turns east in Ken Caryl near Hildebrand Ranch and intersects SH 121 at the western edge of the Chatfield Reservoir. The freeway turns northeast and dips into Columbine as it skirts the northern edge of the reservoir and its dam before coming to an interchange with US 85. SH 470 gains a parallel multi-use trail for pedestrians and bicycles that follows the freeway as it enters Highlands Ranch in Douglas County. The freeway cuts through the northern edge of Highlands Ranch's residential neighborhoods, intersecting SH 177. SH 470 dips to the south to follow Willow Creek around the Park Meadows shopping mall in Lone Tree, terminating at a stack interchange with I-25. The freeway continues east onto the E-470 tollway, which completes a half-loop around the eastern suburbs of Denver.

History

Proposed I-470

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 would be more environmentally friendly.

I-470 to Centennial Parkway

In response to feedback from the Colorado Department of Health, the governor ordered all efforts to plan and build the beltway to cease. A separate commission was established by Governor Richard Lamm to determine the best 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 and widen existing roads.

Centennial Parkway to SH 470

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.

Expansion

After the completion of C-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. Currently, tolled express lanes are under construction along the C-470 portion of the beltway, two westbound toll lanes from Interstate 25 to Colorado Boulevard, and then one westbound toll lane from Colorado Boulevard to State Route 121. Then, there will be one eastbound toll lane from just west of the Platte River overpass to Interstate 25.

E-470

A tollway extension of SH 470, east and north of the SH 470 eastern terminus, was built to the junction with State Highway 83 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

When freeway 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 constructed a continuation of the E-470 tollway from I-25 to an interchange with US 36 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 conjunction with E-470 and SH 470, the Northwest Parkway brings the total length of the completed portion of the beltway around the Denver-Aurora Metropolitan Area to approximately. The uncompleted portion, from the west end of the Northwest Parkway to the northwest end of SH 470, is along existing streets.
In 2007, the Portuguese company BRISA paid $603 million to operate the road for the following 99 years, until 2106. 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

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

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 freeway. If the 20-mile parkway is constructed, Denver will be completely encircled by a "metropolitan beltway."

Exit list

Controversy

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