About CDOT

Construction Timeline

The 449.5 miles of I-70 were built in the following phases across Colorado , east to west:

Between Kansas state line and Burlington (14 miles) Construction Began: 1967 Construction Completed: 1969 Contractor: Schmidt Construction Company Cost: $3.3 million Resident Engineer: W.A. Woodson – Burlington

Between Burlington and Bethune (8 miles) Construction Completed: 1967

Between Bethune and Seibert (25 miles) Construction Completed - two lanes with interchanges: 1966 Construction Began: 1969 Construction Completed – four lanes: 1971 Contractor: Platte Valley Construction Company Cost: $1,967,410 Resident Engineer: W.A. Woodson – Burlington

Between Seibert and Flagler (10 miles) Construction Completed: 1974

Between Flagler and east of Genoa (24 miles) Construction Completed: 1975

Between east of Genoa and west of Genoa (4 miles) Construction Completed: 1975 Contractor: Abott and Sterling Paving Cost: $3 million Resident Engineer: Wayne Nesbitt

Between west Genoa and east of Limon (4.2 miles) Construction Completed: 1975 Contractor: Leone Construction Company Cost: $3 million Resident Engineer: Wayne Nesbitt

East Limon Bypass (3.8 miles) Construction Completed: 1975 Contractor: Goodell Brothers Cost: $3.5 million Resident Engineer: Wayne Nesbitt

West Limon Bypass (3.5 miles) Construction Completed: 1975 Contractor: Schmidt Construction Company Cost: $3.2 million Resident Engineer: Wayne Nesbitt

Between west of Limon and Agate (19 miles) Construction Completed – two lanes with interchanges: 1963/four lanes: 1968

Between Agate and Deer Trail (12 miles) Construction Completed: 1968

Between Deer Trail and Byers (12 miles) Construction Completed: 1967

Between Byers and Bennett (12 miles) Construction Completed: 1964

Between Bennett and Watkins (9 miles) Construction Completed: 1963

Between Watkins and East Colfax Avenue in Denver area (7 miles) Construction Completed: 1977

Between East Colfax Avenue and Peoria Street (7 miles) Construction Completed: 1966

Between Peoria Street and Colorado Boulevard (5 miles) Construction Completed: 1965

Between Colorado Boulevard and Interstate 25 Junction The first segment of I-70 to be built in Denver was through the northeast section of the city, along the route of 46 th Avenue . Construction of the 2.6 mile segment between Jackson Street (just west of Colorado Boulevard ) and the junction of I-25 started in 1961. The six-lane I-70 Viaduct was completed on September 12, 1964 for $12.5 million.

PRIME CONTRACTORS

  • Leon K. Suhm, Incorporated
  • A.S. Horner
  • Ramsour Brothers
  • Peter Kiewit Sons' Company

POINT OF INTEREST> Originally built in 1951 as an interchange at 46 th Avenue with what would become I-25, the interchange was nicknamed “The Mousetrap” in the late 1960s. It was dubbed by an airborne traffic reporter who described the connecting interstates as a maze that could trap a mouse. It currently serves an average of 416,000 vehicles daily, making it the busiest interchange in Colorado . In 1984, a truck carrying six Navy torpedoes overturned in the Mousetrap, closing both highways for hours and causing a large-scale evacuation of nearby neighborhoods. That served as the impetus for its reconstruction, beginning in 1987 and completed in 2003.

Between Interstate 25 Junction and Sheridan Boulevard Construction on the second segment began on October 21, 1964, along a route that generally followed West 48 th Avenue through northwest Denver . Work on the segment between I-25 and Federal Boulevard was completed on December 10, 1965.

Construction between Federal Boulevard and Sheridan Boulevard began on November 27, 1964. It was opened to traffic on July 9, 1966. Cost: $4,501,000

PRIME CONTRACTORS

  • Peter Kiewit Sons' Company
  • Northwestern Engineering Company
  • Thomasson Concrete Company
  • A. Keesen and Sons

Resident Engineer: Robert W. Linke

POINT OF INTEREST> The major challenge of this segment involved threading an interstate highway past Rocky Mountain Park, past Rocky Mountain Lake, Berkeley Lake, Lake Rhoda (Lakeside Amusement Park) and between Berkeley Park and Willis Case Golf Course. It entailed deepening Berkeley and Rocky Mountain Lakes , to keep their water capacity unchanged by compensating for a minimal loss of surface area. What emerged was a gently winding and beautifully landscaped section of I-70.

Between Sheridan Boulevard and Wadsworth Boulevard (2 miles) Construction Completed: 1967

Between Wadsworth Boulevard and Kipling Street (2 miles) Construction Completed: 1968

Between Kipling Street and Ward Road (1.7 miles) Construction Began: 1967 Construction Completed: 1968

Between Ward Road and West Colfax Avenue - U.S. 40 (4 miles) Construction Completed: 1970

Between West Colfax Avenue and State Highway 26/U.S. 40 Junction – entrance to Mount Vernon Canyon (2.9 miles) Construction Began: 1967 Construction Completed: 1969 Cost: $4,728,558

PRIME CONTRACTORS:

  • Colorado Constructors, Inc.
  • A.S. Horner Construction Company, Inc.
  • Peter Kiewit Sons' Company

POINT OF INTEREST> This section of I-70 slices through a prominent terrain feature called the Hogback. It was formed 50 to 80 million years ago with the gigantic upheaval that produced the Rocky Mountains . The Hogback is not simply layers of nondescript rock, tipped on end. The strata stand out in beautiful, well-defined pastel bands. The site now is a nature study area complete with marked trails to points of special interest.

Between State Highway 26 and Lookout Mountain Exit – Mount Vernon Canyon (2.8 miles) Construction Began: Construction Completed: 1970 Cost: $2.3 million

PRIME CONTRACTORS:

  • Schimkat Construction Company
  • Asphalt Paving Company

Resident Engineer: Russel A. Glad

POINT OF INTEREST> Runaway Truck Ramps are part of the landscape along some of I-70's steeper downhill grades. These ramps are designed to stop trucks from going out of control when they experience brake failure or due to other circumstance. After a number of truck accidents and runaway trucks on the steeper highway grades in the 1970's, CDOT decided to build the ramps at key mountain highway locations. Five ramps are in service along the I-70 corridor: one on eastbound I-70 in Mount Vernon Canyon , two on westbound I-70, west of the Eisenhower Tunnel, and two on westbound I-70, west of Vail Pass.

Between Lookout Mountain Exit and Genesee Mountain (2.4 miles) Construction Completed: 1970 Cost: $2.1 million

PRIME CONTRACTOR:

  • H-E Lowdermilk Company

Resident Engineer: R. J. Brasher

Suggested Photo: Genesee Bridge looking west towards Continental Divide

Between Genesee Mountain and El Rancho Exit (2 miles) Construction Completed: 1972

Between El Rancho Exit ( Evergreen Parkway ) and Beaver Brook (4.0 miles) Construction Began: 1970 Construction Completed: 1972

Between Beaver Brook and Junction U.S. 6 (4 miles) Construction Completed: 1975

Between Junction U.S. 6 and east Idaho Springs (3 miles) Construction Completed: 1961

Between east & west Idaho Springs – Idaho Springs Bypass (2 miles) Construction Completed: 1961

Between west Idaho Springs and Junction U.S. 40 – Empire (7 miles) Construction Completed: 1966

Between Junction U.S. 40 and Silver Plume (6 miles) Construction Completed: 1968

Between Silver Plume and Eisenhower Tunnel (10 miles) Construction Completed: 1972

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