Portions of Interstate 8 construction advancing quickly
Progress is advancing at a greater pace than anticipated for some of the initial segments of the $417 million Interstate 8 Update Project, which will eventually replace 48 total miles of roadway between El Centro and the Arizona border.
Currently, three out of a total of five construction projects are underway, with two of the first three segments projected to be completed several months ahead of time, California Department of Transportation officials said.
Once installed, the new roadway is expected to last about 60 years, replacing a roadway that is about 50 years old, said I-8 project manager Ismael Salazar.
“Rather than do it piecemeal, we decided to do it all at once,” Salazar said. “This is (Caltrans’) biggest investment in Imperial County, ever.”
The construction projects currently underway consist of three separate segments that together span nearly 26 miles, have a combined cost of $317.9 million and were, on average, projected to take at least two years to complete.
All told, the three segments will utilize about 30 million pounds of American-made steel reinforcement bar and 350,000 cubic yards of continuously reinforced concrete pavement (CRCP), Caltrans reported.
“It’s almost like constructing a bridge,” Salazar said. “I can’t think of anything that we’re doing right now in San Diego or Imperial County that compares.”
In order to expedite construction and lessen impacts to motorists, Caltrans project designers had analyzed which highway ramps to close and where to route detours prior to work having gotten underway in March 2015.
The project’s preliminary work also included the creation of “crossovers” at each respective segment’s beginning and end points to be used to divert traffic away from construction zones and onto alternate roadways. Although not envisioned as part of the overall project’s original design, a contract change order was approved to allow an eightmile portion of Evan Hewes Highway to be used as a crossover for Segment 2 construction.
The benefits of using Evan Hewes Highway as a crossover include having two lanes of westbound traffic open as opposed to one, expedited construction on the project segment and the county getting a newly rehabilitated road, said Dan Juarez, Caltrans District 11 senior resident engineer.
“It’s a win-win all around,” Juarez said.
The rehabilitation of that particular segment of Evan Hewes Highway came at a cost of about $3.5 million, which is a few hundred thousand dollars more than what Caltrans would’ve spent on creating and subsequently demolishing crossovers for Segment 2, Juarez said.
The three construction projects currently underway consist of three separate segments, with Segment 1 spanning a total of 9.5 miles beginning slightly west of the Anderholt Road overcrossing and ending slightly east of the East Highline Canal Bridge.
Segment 1 is also where road crews encountered “quite a bit of clay” that posed problems for roadway construction, Juarez said. While underlying clay that is not exposed to moisture typically does not pose any issue to roadway construction, clay that is ex- posed to moisture can expand and pose a problem to construction, Juarez said.
Unlike other segments of Interstate 8 that pass through desert wilderness, large swaths of Segment 1 are bordered by farmland whose water usage tends to have adverse effects on the clay found beneath the roadway, Juarez said.
“On Segment 1 we spent a little over $3 million on subbase because of the clay,” he said.
Subgrade is composed of crushed rock and other materials used underneath a roadway’s asphalt layer, which in turn is topped by CRCP.
Like Segment 1, Segment 2 also spans 9.5 miles and begins less than a mile west of the Route 98/I-8 Separation and ends about half a mile east of the All American Canal. Construction on both these segments is rapidly advancing and is projected to finish nearly a year ahead of schedule, Caltrans officials said.
Segment 3 spans 6.8 miles and begins about half a mile west of the Route 186/I-8 Separation and runs about half a mile east of the Fourth Avenue overcrossing. This segment passes through Fort Yuma Indian Reservation land and employs Quechan tribal members as a condition of the project contract.
“They have their own requirements that Caltrans has to adhere to,” Salazar said, referring to the Tribal Employment Rights Ordinance (TERO) program, which mandates the use of eligible Native Americans on construction work performed on tribal reservations by outside parties.
Segment 3 is also where progress has not kept pace with the other two segments, partly as a result of its close proximity to the Arizona border, which has restricted construction crews from maintaining nearby staging areas, Juarez said.
Despite the relatively slower progress, Caltrans officials are hoping to be able to keep their promise to the Quechan Tribe that the Algodones Road freeway ramps that lead to and from their casino will be open by Dec. 16, Juarez said, before adding a caveat.
“There’s never a 100 percent guarantee in any construction site because you never know what’s going to happen,” he said.
The I-8 update project is also notable in that it will install shoulders made of concrete in place of the asphalt that is typically used for highway shoulders.
The concrete shoulders will eliminate the need to have maintenance crews treat asphalt shoulders with oil every five years to prevent oxidation.
“It became more cost effective to do the entire thing out of concrete,” Salazar said.
The Interstate 8 Update Project is essentially five separate projects that were made possible by funding specifically set aside for road rehabilitation. Work on the remaining two segments is expected to start in spring 2017. In contrast to ongoing roadway work, segments 4 and 5 will install new CRCP on top of existing concrete roadway.
The resulting roadway will create stretches of elevated highway that in turn will require additional work to ensure smooth transitions onto shoulders.
The elevated stretches of highway associated with segments 4 and 5 will also require construction crews to remove the old concrete and excavate underneath freeway overpasses in order to maintain the same height clearance for motorists, namely truckers with cargo trailers, Juarez said.
Since construction started, Caltrans officials have not identified any traffic accidents that are directly attributable to ongoing construction. It is also estimated that the ongoing construction has resulted in a 15-minute delay traveling the distance from El Centro to Yuma.
A large volume of traffic control signs have also been installed to ensure motorists are aware of the changing surroundings and conditions, as well as keep motorists’ speeds to safe levels.
“There’s workers out there and they all want to get home to their families,” he said.