In one review, CBP forced MKA to redo the structure for the primary inspection canopy. During preliminary design, MKA used a 10-ft-deep box truss to reduce the number of columns in the inspection area to three from 52. CBP rejected the truss because it was too deep and blocked sight lines from the nearby headhouse to traffic lining up in Mexico. The solution was a 2-ft-deep cable-stayed system.
The design team issued construction documents in February 2011, two months earlier than expected. Miller Hull's Curtis attributes the speed to HP advising on constructibility during design development.
HP has a guaranteed maximum price that grew to $181 million from $160 million, due to owner changes. To "eat the elephant" in small bites, HP broke the work into 13 phases. The initial plan had only nine.
HP's strategy for the I-5 work was to add six temporary booths, each in tandem with an existing booth. That allowed HP to take six lanes out at a time, yet maintain the original number of booths.
Controlling traffic flow from Tijuana during the work posed another challenge because no personnel were allowed to enter Mexico. To control traffic, HP hired U.S. company Hudson Safe-T-Lite Rentals, which has a subsidiary in Mexico.
The first two or three months of construction were dedicated to installing underground infrastructure. For temporary electric service until the headhouse control room was finished, Bergelectric installed several temporary panel boards. "That allowed us to plug-n-play the port," says HP's Wellenstein.
The most challenging part of Bergelectric's job was wiring the 25 northbound lanes and the new permanent tandem booths. For this, crews had to work night shifts, during lighter traffic times, to dig under all of I-5's lanes, which were closed incrementally. Prefabrication of 45% of the duct banks minimized sitework.
Bergelectric's SYLPOE planning, which relied on building information modeling, took three times longer than planning for most jobs, says Kuhn.
URS' McCoy considers the first phase a big success. "It's a dynamic project, yet all the properties were built on time," he says. Wellenstein concurs, saying HP will "absolutely" bid on phase two.
