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

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

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:

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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EISENHOWER-JOHNSON MEMORIAL TUNNELS

Length: 1.7 miles

Cost: $117 million (Eisenhower Tunnel Bore)

Cost: $-145 million (Johnson Tunnel Bore)

Construction Began: 1968 (Eisenhower Tunnel Bore)

Construction Began: 1975 (Johnson Tunnel Bore)

Completion: March 8, 1973 (Eisenhower Tunnel Bore)

Completion: 1979 (Johnson Tunnel Bore)

To alleviate the distance and rigors of travel over U.S. Hwy. 6 at Loveland Pass , the Colorado Department of Highways developed plans for two two-lane tunnels beneath the Continental Divide three miles from Loveland Pass at elevation 11,000 feet.

The Eisenhower Tunnel Bore, today's westbound bore, was the first tunnel completed. It was planned for three years but actually required five years due to unanticipated hazards and the harsh climate. The tunnel bore was 50 feet high and 45 feet wide.

The Eisenhower Memorial Tunnel was dedicated on March 8, 1973. Federal funds had accounted for about 92% of the $108 million cost. At the height of construction, more than 1,140 persons were employed in three shifts, 24 hours a day, six days a week. The prime contractor was actually a consortium of four contractors – Al Johnson Construction Company ( Minneapolis , MN); Gibbons & Reed Company ( Salt Lake City , UT ); Kemper Construction Company ( Los Angeles , CA ); and Western Paving Construction Company ( Denver , CO ).

The Edwin C. Johnson Memorial Tunnel, named for the Colorado legislator, lieutenant governor, governor, and U.S. Senator, required more than 800 workers. Just under 500 of those workers were employed in actual drilling operations. Work began at both the east and west sides; the first hole connecting the two was blasted on August 17, 1978.

Between Eisenhower Tunnel and Silverthorne (7 miles) Construction Completed: 1973

Between Silverthorne and Frisco (5 miles) Construction Began: 1971 Construction Completed: 1972

Between Frisco and Wheeler Junction – Tenmile Canyon – Junction State Highway 91 (6 miles) Construction Began: 1976 Construction Completed: 1979

PRIME CONTRACTOR:

• Colorado Constructors, Inc.

POINT OF INTEREST> As part of constructing the interstate through the canyon, a new stream bed had to be built for three of the six miles of Tenmile Creek, from Frisco west. Changing the channel was required since construction would have required frequent stream crossings of the meandering creek. The modification involved several state and federal agencies and Trout Unlimited. The Colorado Division of Wildlife said it was the first time in history that a stream had been re-channelized and the fishing improved. Tenmile Creek is home to at least three varieties of trout: brook, native cutthroat and rainbow.

Between Wheeler Junction and east Vail (15 miles) Construction Began: 1969 Construction Completed: 1978

PRIME CONTRACTORS:

• Kiewit Western Company
• Colorado Constructors, Inc.

POINT OF INTEREST> What route to take? The Vail Pass segment was the subject of much controversy before it was constructed along a route that parallels or shares much of the U.S. 6 route. The Colorado Department of Highways (CDOH) originally proposed to build I-70 west from Silverthorne via the South Willow Creek alignment, through the Eagles Nest Wilderness Area, tunneling under the Gore Range and Red Buffalo Pass, and continuing west via the Gore Creek alignment to Vail (see map). The CDOH dropped the idea after many adversarial public hearings where there was much opposition to going through a wilderness area (see map).

The construction of I-70 over Vail Pass is an excellent illustration of what can be accomplished in an environmentally sensitive area. Innovative construction methods were used to insure maximum preservation of environmental values, including:

Numerous awards have recognized the highway's construction since Vail Pass was truly a monument to working with Mother Nature, not taming her.

Between east Vail and Dowd Junction area - U.S. 6 & 24 (6 miles) Construction Began: 1967 Construction Completed: 1968 Cost: $2,711,132

PRIME CONTRACTOR:

• Pioneer Construction Company

Resident Engineer: Vernon Leonard

Project Engineer: Calvin Edwards

Between Dowd Junction area and Avon (4 miles) Construction Completed: 1970 Contractor: Pioneer Construction

Between Avon and Wolcott (10 miles) Construction Completed: 1971

Between Wolcott and Eagle (10 miles) Construction Completed: 1973

Between Eagle and Gypsum (8 miles) Construction Began: 1977 Construction Completed: 1979 Cost: $13.5 million Resident Engineer: Jim Nimon

Between Gypsum and East End of Glenwood Canyon (7.8 miles) Construction Completed: 1980

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GLENWOOD CANYON I-70 FINAL LINK

Length: 12 miles

Cost: $490 million

Construction Began: 1980

Construction Completed: 1992

A road had existed through spectacular Glenwood Canyon , with its cliffs towering a maximum of 2,000 feet above the Colorado River , from pioneer times. Photos of teams and wagons negotiating a rough trail through the canyon date from the 1880s.

The Taylor State Road was completed between Denver and Grand Junction in 1902. It was the first improved vehicle road through Glenwood Canyon .

The final link of I-70 through Glenwood Canyon has been hailed as an engineering marvel because of the care taken to incorporate the interstate improvements into the fragile canyon environment while leaving as much of the flora and fauna intact as possible.

As many as 500 highway workers were employed in the canyon each day. The public driving through the area marveled at the new retaining walls, 40 viaducts and bridges, some of which were construction using unique and spectacular slip-form gantry imported from France . At traffic sometimes that sometimes approached 30 minutes or more, drivers had a chance to get out of their vehicles and watch first-hand at the construction activities going on around them.

Construction of three tunnels, 15 miles of retaining walls, and numerous other structures, comprised a challenging but very rewarding project. The Glenwood Canyon project required 30 million points of structural steel, 30 million pounds of reinforcing steel, and 400,000 cubic yards of concrete weighing 1.62 billion pounds.

The result of the Glenwood Canyon I-70 Final Link is much more than just a transportation facility. State-of-the-art rest areas at No Name, Grizzly Creek, Hanging Lake , and Bair Ranch provide opportunities for rest, education about the canyon and the project, and direct access to recreational pursuits such as river rafting and bicycling/jogging/walking along the canyon's recreation path.

Between No Name and Glenwood Springs (3 miles) Construction Began: 1964 Construction Completed: 1966

Between Glenwood Springs and Chacra (7 miles) Construction Completed: 1971

Between Chacra and New Castle (4 miles) Construction Completed: 1971 Cost: approximately $4 million

PRIME CONTRACTOR:

• Northwestern Engineering Company
• Corn Construction Company

Resident Engineer: Glen W. Jones

Between New Castle and Silt (8 miles) Construction Completed: 1973

Between Silt and west Rifle (11 miles) Construction Completed: 1976

Between west Rifle and Rulison (6 miles) Construction Completed: 1980

Between Rulison and Parachute (6 miles) Construction Completed: 1983

Between Parachute and De Beque (13 miles) Construction Completed: 1984

Between De Beque and Junction State Highway 65 – De Beque Canyon (13 miles) Construction Began: 1985 Construction Completed: 1989

POINT OF INTEREST> Within De Beque Canyon, the Beavertail Tunnels go through Beavertail Mountain . The tunnels are unique for two reasons. One, they are designed with curved sidewalls, a design incorporated into several European tunnels. Curving the sidewalls creates a superior structural section and makes the tunnels appearance more pleasing. The Beavertail Tunnels are the only ones in the country incorporating curved sidewalls. Two, there were no explosives used during excavation. A very large rotating cutter mounted on a crawler tractor chiseled the sandstone and shale bedrock to the next lines of the tunnel section.*

*From the book Building I-70 by Dick Prosence, former CDOH District Engineer

Between Junction State Highway 65 and Clifton (12 miles) Construction Began: 1960 Construction Completed: 1963

POINT OF INTEREST> This segment was the first I-70 construction project west of the Continental Divide in Colorado . Work consisted of the bridge over the Colorado River , east of Palisade. When it opened in 1963, it also was the first operational section in use west of the Divide.

Between Clifton and Horizon Drive - north Grand Junction (6 miles) Construction Completed: 1965

Between Horizon Drive and 22 Road (5 miles) Construction Began: 1965 Construction Completed: 1967

Between 22 Road and Fruita (6 miles) Construction Began: 1967 or 1968 Construction Completed: 1969

Between Fruita and Mack (8 miles) Construction Completed: 1972

Between Mack and Utah State Line (11 miles) Construction Completed: 1973

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