Full Circle

Red Mountain Freeway Completes East Valley Loop

By Scott Blair

The final section of the Red Mountain Freeway in Phoenix's east valley will complete a route two decades in the making. Featuring miles of roadway, numerous bridges and complicated flood management facilities, finishing this project won't be easy.

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An epic saga two decades in the making, Red Mountain Freeway's road to completion started in 1985 with the passage of a half-cent sales tax by Maricopa County voters. 22 years later, motorists will be able to drive in a complete loop around the cities of Tempe, Mesa, Chandler and Gilbert upon completion of the final two sections between Power Road and Southern Ave. in late 2008.

The 4.83-mi section between Power Road and University Drive is the largest of the two projects. Phoenix-based contractor Pulice Construction Inc. was awarded the project and began construction in February 2006. Coming in at a cost of $195 million, it is one of the largest single projects the Arizona Department of Transportation has ever done.

It is also one of the fastest timelines for such a complex project, with a completion date of September 2008.

"We were looking at a relatively short timeline for design delivery and the construction phase while coordinating with many outside agencies to get this project done," says Mike Bruder, project manager with ADOT.

The second project, located immediately to the south, is valued at $67.4 million and will construct 2.1 mi. of six-lane urban freeway from University Drive to Southern Avenue. Parsons Brinckerhoff designed this section, with Pulice again as the general contractor.

These are the final two projects funded by Proposition 300, a sales tax that was implemented 22 years ago to fund regional transportation projects.

Both projects cross land controlled by a variety of city, county and state governmental agencies. The larger project passes through a Maricopa County Flood Control area, requiring the partial relocation of a dam and its impoundment.

"It was very complex from drainage, geotechnical, the dam and the sheer magnitude of just the roadway improvements themselves," says Michael Chase, P.E., vice president and principal transportation engineer with the Phoenix office of Stanley Consultants, the lead design firm on the Power-University section.

This section required the movement of over 5 million cu yds of material, partly due to the relocation of the impoundment.

"We've created the same amount of impoundment but in a smaller area because the freeway footprint took up what used to be floodplains" says Steve Campbell, project manager with Pulice.

The project was able to utilize 3 million cu yds of the material in other areas of the project, with 2 million hauled off as waste. "At times on our off-site haul, we were running up to 120 trucks a day," Campbell says.

The area will be contour-graded in consideration of a future park for the city of Mesa, according to Chase.

Crews are also modifying the 18,000-ft-long length of the dam by installing a filtering device meant to strengthen the dam and reduce fissuring, a common problem afflicting flood control dams in the Valley.

"We are basically creating a 30-in.-wide slot in the center of the dam and putting in an aggregate central filter material down the middle," says Mark Soyster, vice president of operations with Pulice. In most cases the slot ranges in depth between 25- and 30-ft, but in some spots it exceeds 40-ft deep. "It's very unique and has been a challenge, but we are moving forward." since much of this leg is depressed below grade. Some dirt was reused in a way that pleased nearby residents, according to Frank Medina, Arizona manager for Parsons Brinckerhoff.

"In one area we were able to eliminate the sound wall and replace it with an earthen berm," he says. "It is not as hard of a feature, but is still the same height as the adjoining walls."

The south project has 13 reinforced concrete box culverts, while the Power-University project has 16. The smallest is 8-ft tall by 8-ft wide and 200-ft long, but they range all the way up to 24-ft by 16-ft and 400-ft-long, Campbell says. Many are used for equipment access to the Central Arizona Project canal that runs the length of the project.

Of the seven major crossroads that were part of the two projects, the Power Road bridges are the longest and most unique. The 943-ft-long, 8-span bridges are comprised of pre-cast, pre-stressed concrete girders and also span the CAP canal. Each bridge will carry three lanes of traffic in each direction, but are built 87-ft 8-in. wide to allow for future expansions to four general purpose lanes plus an HOV lane, Chase says.

The bridge design required the use of straddle bent piers. "Because of the large skew of the roadway and the long span, they had to go with this unique system," Soyster says. The four straddle bents are comprised of a series of pre-cast girder plys bolted together to literally straddle the CAP canal. "Then we built the pier columns on top of the straddle bents and then built the pier caps on top of those."

Another unique facet of the project is the use of roundabouts on the McKellips Road and Brown Road interchanges.

"The roundabouts were an integral part of the community involvement, and it was a neighborhood decision. They were chosen because modern roundabouts have been proven to increase safety over traffic signals," says Diane D'Angelo, public spokesperson for ADOT.

Key Players

Owner:
Arizona Dept. of Transportation

Design:
Stanley Consultants; Parsons Brinckerhoff

General Contractor:
Pulice Construction

Subcontractors:
McNeil Brothers; Endo Steel; CS Construction; Carlson Masonry

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