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Major Projects on I-25, 1990-2005

I-25 Widening Safety Project, Lincoln Ave. to Castle Pines, Douglas County

Approval for the addition of a slow-vehicle climbing/descent lanes on the four-mile I-25 segment from Lincoln Avenue to Castle Pines North in Douglas County was received from Congress in November, 1997. Project cost: $19.7 million. Began: July, 1998. Completion: 2000. Planning for the improvements was already underway when, in February of 1997, 82 vehicles were involved in accidents during a “routine” snowstorm on I-25 at Surrey Ridge. Two dozen people were injured and the freeway was closed for 10 hours.

I-25 Mousetrap/North Improvements Program, Denver

This multi-year program was planned after the torpedo incident in the Mousetrap (intersection of I-25 & I-70 northwest of downtown Denver ) on August 1, 1984.

In 1987, the 44 th Ave. , bridge over I-25 was replaced and I-25 beneath was widened to accommodate future HOV lanes. In 1989, construction of the new I-70 bridges over I-25 began. These bridges were completed and the ribbon cutting was held Dec. 27, 1991.

Improvements on I-25 in the area from 20 th Avenue north to 70 th Avenue continued largely unabated from 1987 until 1995. The freeway was widened, accesses were improved, and two high occupancy vehicle (HOV) lanes were built in the center of the freeway between 20 th Avenue near downtown to the 70 th Avenue bridge. The HOV lanes were open to southbound vehicles with two or more passengers in the morning hours, and northbound in the afternoon rush hours. The lanes were also used to help heavy traffic rushes out of central Denver after large special events are held, such as Bronco football games at Invesco Field at Mile High.

Other major I-25 improvements in the area included the Park Avenue Flyover (see below), improved ramps between I-25 and I-70, reconstruction, widening, and realignment north of I-70 on I-25, and work in the intersections of I-25 & U.S. 36, and I-25 & I-270. The completion of HOV lanes north to 58 th Ave. occurred in 1995; the lanes were later extended on to 70 th Avenue as well as to U.S. 36 to the vicinity of the Sheridan Blvd. interchange.

T-REX, Denver

The T-REX project, the largest multi-modal transportation project in Colorado history, began in September, 2001, and will conclude in November, 2006, two years ahead of its initial completion target date. The $1.67 billion project will widen and install safety improvements along 19 miles of I-25 and I-225 in Denver , will add 19.7 miles of light rail line, and will rebuild eight interchanges. The format is design-build, meaning that the project is being designed as it is being built. Public perception of project progress has been favorable. Few problems other than ever-growing traffic volumes on the corridor have been noted during the construction period.

Park Avenue Flyover Ramp, Denver

Precast concrete girders 121 feet in length and weighing 400,000 pounds, heavier than five loaded semi-trucks, highlighted the flyover ramp dubbed as the “Gateway to Downtown Denver.” The purpose of the ramp was to streamline commuter traffic into the downtown area, especially by allowing eastbound and westbound traffic on I-70 to have a direct link to it and bypassing I-25 completely. Other features of the project which completed the mousetrap and north I-25 improvements included additional through-lanes on I-25 both north and southbound, improved access to the freeways from Park Avenue westbound commuter traffic, and reconstruction of Globeville Road . The total cast was $48 million. Dedication was held on November 30, 1998.

Wolfensberger Interchange Improvements,
I-25 in Castle Rock

Ground was broken on May 23, 1995, for improvements at a major interchange in Castle Rock along I-25. Total cost: $2.8 million. A new four-lane bridge was built over I-25, ramps were improved, and left turn lanes from Wolfensberger to I-25 were added, eliminating the long traffic backups that had plagued the area. The project is notable because the Plum Creek area beneath the bridges was found to be habitat of the endangered Preble's Meadow Jumping Mouse. Environmental protection of this habitat and mitigation of loss of nearby wetlands brought much positive recognition to CDOT's environmental banking program. The project was completed in December, 1995.

COSMIX, Colorado Springs

Colorado Governor Bill Owens officially broke ground on the Colorado Springs Metro Interstate Expansion (COSMIX), a 2.5-year, $150 million program to increase I-25 capacity through the north side of Colorado Springs by widening the freeway to three lanes in each direction from Circle Drive to North Academy Boulevard and reconstructing the Bijou Street and North Nevada/Rockrimmon Boulevard interchanges. COSMIX is the largest transportation project ever undertaken in the rapidly-growing Colorado Springs area. Governor Owens stated that when I-25 opened in Colorado Springs in 1960, the highway carried about 8,500 vehicles day. In 2005, as COSMIX was getting underway, the average daily vehicle count in the COSMIX project area was 100,000 vehicles per day. By 2020, that number was expected to rise to 170,000 vehicles per day.

North Forty Project, Southwestern Weld County

A major $73 million project to widen and improve seven miles of I-25 from State Highway 7 to Weld County Road 16 kicked off on Dec. 19, 2001, with remarks by Colorado Governor Bill Owens. The project, dubbed the “North Forty”, widened the freeway to three lanes in each direction, installed 12 foot shoulders, reconstructed the Erie and WCR 8 interchanges (a park-n-ride was installed at WCR 8), and rebuilt the east Frontage Road. The project was completed in October, 2004.

I-25 North Corridor Improvements, Colorado Springs

CDOT announced in August, 1992, that plans called for spending $80 million for improvements, including soundwalls, interchanges, safety projects, and the complete reconstruction of the road between Fillmore and Bijou streets, in the decade of 1995-2005.

There were seven phases in this project, which ran for more than a decade. The first project, which reconstruction the interchange serving the South Entrance of the U.S. Air Force Academy, North Academy Boulevard , and SH 83, begin in March, 1997, and was completed in Nov., 1997, seven months ahead of schedule.

Other major work included reconstructing the SH 105 interchange at Monument, reconstruction I-25 between Bijou Street and Fillmore, a distance of 2.5 miles; reconstruction of interchanges at Nevada/Tejon and Circle Drive/Lake Avenue; rebuilding the Fountain Creek Bridges on South Academy Blvd. near Ft. Carson, and the reconstruction of the Woodmen Road Interchange on the north side of Colorado Springs.

A unique feature of the multi-year program was installation of 1,000 noisewall barrier panels along the west side of I-25, beginning in January, 1998, as a part of the Bijou to Fillmore reconstruction. The panels featured art designs that recall important historical and natural features of the Pikes Peak Region.

The program concluded in May, 2005, with completion of the SH 105/Monument project a few miles north of Colorado Springs.

Total cost: $190

Owl Canyon I-25 North Project

This project was one of the Colorado Transportation Commission's 7 th Pot (28 strategic corridors in Colorado ) projects. The project started north of Wellington , CO at milepost 282 and ended at the Wyoming state line (milepost 299), a total distance of 17 miles.

This was an “A + B” design-build contractor; the prime contractor Castle Rock Construction partnered with design firm GMJM Inc. to win the contract. The $26.3 million contract was awarded in February, 1998.

Work on the southbound portion began in May, 1998, and was completed in the fall of 1998. Work was suspended over the winter of 1998/99 and resumed in April, 1999, on the northbound lanes. The northbound side was completed in October, 1999. The entire freeway was rebuilt in concrete. Other improvements included refurbishing bridge decks, installing new bridge rails and guard rails, flattening side slopes, installing new signs, and making drainage improvements. Final project acceptance, after final reseeding, was June 6, 2001.

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