By Kevin Flynn
Inside-Lane.com

The dirt is starting to move in the $40.1 million design-build reconstruction of four miles along Hampden Avenue, starting at the east end of the corridor with replacement of the bridge over Federal Boulevard.

Inside Lane takes you on a tour of the job with this video featuring the project managers, plus a slide show.

There is a short story about the project below the slide show.

Hampden Bridge Project at Federal from K J Flynn on Vimeo.

You can view a slideshow of the work. The photos were taken on Friday, March 5.

To expand to full screen and read the captions, first click on the “play” button and then click on the box that will appear at the lower right corner — with the four little arrows pointing outward. When the full screen appears, click on “Show Info” at the menu bar on the top right.

The team of Concrete Express Inc. and Tsiouvaras Simmons and Holderness is doing the work. With construction at Federal well underway, crews will next start in on the Wadsworth Boulevard bridge replacement. The Pierce Street structure also will be replaced. Hampden will be rebuilt in concrete except for the western one-mile portion, which will be asphalt. The portions of the median that are now grass will be paved over with a center concrete barrier, similar to the segment between Knox Court and Sheridan Boulevard, to widen the roadway. It will remain striped for four lanes rather than six, however.

Under the design-build method of project delivery, the Colorado Department of Transportation establishes the scope and goals of the program and provides early design work, to the 30 percent level. It then puts the program on the market and, instead of taking the lowest bidder as in the traditional design-bid-build model, it looks for the team that brings the best value to the project. The winning team completes both the design and the construction, and savings it finds go to fund the options that are added.

When used in the right projects, design-build can help stretch scarce transportation dollars, which don’t go as far as they used to.

Read more here about the project at CDOT’s web site.

The Concrete Express/TSH team proposed several additions to the scope including reconstruction of four miles, toward Kipling Street, instead of just three miles. It did that by using less expensive methods on the bridge reconstructions – using clear-span structures to make the three crossings without center piers – and plowed the savigns into added scope for the project.

Design-build is how CDOT and the Regional Transportation District did the $1.75 billion T-REX reconstruction of Interstate 25 and 225, with new lanes and light rail. This is the largest project CDOT has done with this method since then.

Hampden Avenue was once State Highway 70. It ran west out of Englewood, across the South Platte River on an older bridge near the old Cinderella Twin Drive-In and through Sheridan until it detoured south on Lowell then west on Kenyon Avenue, on the north side of Fort Logan National Cemetery to Sheridan Boulevard. It then went straight west to Morrison.

The plan early on was to make Hampden across-town freeway along the south metro suburbs to Interstate 25. Work began on grade separations at major intersections. The bypass under Broadway in Englewood was first, in 1955. A new bridge across the Platte was done in 1960 – upgraded in 1985 – and the intersection at Federal was grade-separated in 1961 with a new alignment parallel to Old Hampden. Raleigh Street and Sheridan Boulevard were bridged a year later, with Pierce and Wadsworth grade-separated in 1964.

Kipling Street was bridged in 1967. By this time, plans to make Hampden a full freeway across town were in the mix with the proposed partial beltway, Interstate 470. After Gov. Richard Lamm campaigned against the beltway, the state formed a commission to study transportation in the southwest metro area.

An alternative to I-470 in that 1975 study was to use Hampden as a freeway instead. One alignment had traffic coming from Interstate 70 on a diagonal to Hampden and Simms Street, then east to I-25. Another used I-70 to Sixth Avenue, then on a freeway connection down Kipling Street to Hampden and east.

Another alternative had the freeway running along Belleview Avenue.

Those were rejected in favor of today’s C-470, on the same alignment as the defunct I-470.

You can read about the brouhaha over I-470 and southwest metro freeway alignments at Matt Salek’s Highways of Colorado web site.