The $230-million Ambassador Bridge Gateway Project in Detroit constitutes the largest project in Michigan Department of Transportation (MDOT) history. Three phases have been completed:
• Rehabilitation of Fort Street from Clark Street to Rosa Parks Boulevard
• Reconstruction of the West Grand Boulevard Bridges over I-75
• Reconstruction of the I-96/I-75 southbound service drive and the I-96 off-ramp from Vernor Highway to Michigan Avenue.
The $170 million fourth phase is the largest single contract project in the Michigan’s history and is expected to generate 2,800 jobs. Work includes:
• Construction of a signature cable-stayed pedestrian bridge over I-75 and I-96 connecting east and west Mexicantown
• Reconstruction of 1.5 mi. (2.4 km) of main line paving on I-75 from Rosa Parks Boulevard to Clark Street
• Reconstruction of 1 mi. (1.6 km) of main line on I-96 from the I-75/I-96 interchange north to Warren Avenue
• Reconstruction of 18 ramps and bridges on I-75 and I-96
• Construction of new ramps between the freeway and the proposed Ambassador Bridge Plaza and between the freeway and Vernor Highway
• Erection of 3 mi. (4.8 km) of retaining wall along the reconstructed freeway.
Goals
When I-75 was built through Mexicantown, it divided the community.
“The dream was always to reconnect the community. This plan has actually been in the works for 30 years,” said Brenda Peek, communications manager for The Gateway Project.
The lighted cable-stayed bridge, Michigan’s first, will span I-75 at Bagley Avenue. It will provide access to the new Detroit Mexicantown International Welcome Center and Mercado and other businesses. The Mexicantown Mercado features a business incubator with new businesses showcasing products from Mexico and authentic Mexican food.
Reconnecting the neighborhood isn’t the only mission of the project. Improved traffic flow between Detroit and Windsor, Canada, will benefit the area’s economic health. The international border handles $115 billion in trade annually, making it the busiest international crossing in North America, and the area contributes a significant portion of the state’s $5 million tourism revenue.
Project goals include increasing the safety and efficiency of the border crossing; providing a direct connection from I-75, I-96 and other area freeways with an improved network of ramps to the Ambassador Bridge and the city; providing better access to the Welcome Center and Mercado; and new landscaping and lighting.
The key to improving traffic flow is getting traffic off local streets, Peek said. Trucks crossing the Ambassador Bridge Plaza will no longer use city streets, making the area safer, she said. Dedicated ramps for trucks will separate them from main line I-75, allowing traffic to flow more freely through the area.
Progress
Phase four work began in February 2008 and is scheduled to be completed by December 2009, with landscaping and cleanup continuing in 2010. During construction, I-75 between Clark St. and Rosa Parks Blvd. is closed to traffic. Because the work is so disruptive, the plan was designed to interrupt traffic for only 22 months, as opposed to four years if the freeway remained open. Calling it “a unique project,” MDOT Senior Delivery Engineer Victor Judnic specified that “everything is open for business but the freeway.”
An even more abbreviated disruption may be in the works. In a press release, MDOT metro region engineer Greg Johnson stated, “Our current progress schedule will have the entire area fully reopened to traffic even sooner than the original December 2009 projected date.” One mi. on I-75, 1 mi. on I-96 and 3 mi. (4.8 km) of freeway retaining and sound-reduction walls have been rebuilt. Of the ramps and bridges impacted by the project, MDOT has removed four structures, replaced two and rehabilitated seven.
Peek credited fair weather and an effective executive team for pushing work ahead of schedule. She estimated that in just one year after starting construction, the project is 70 percent complete. To be precise, Judnic calculated that as of the end of January, the project is 74 percent complete in only 56 percent of the allowed time, indicating the margin by which they’re beating the deadline.
Judnic said the reason work is a month ahead of schedule is due to $8 million in incentives to finish early, but also some switched staged work.
“We did some of the 2009 work in 2007. That got us ahead. We finished one mile last summer; now we’re in the middle third of the last mile.”
The contractor also completed utility work in 2007, which posed the challenge of community coordination in order not to disturb area businesses. In 2008, Judnic said crews were “back to the freeway, down in a hole. The neighborhood was happy because we weren’t so visible and they couldn’t hear us.”
Crews have been working long days on a standard six-day week. Except for clean-up and painting, Judnic said no night work is necessary.
“The two-shift system doesn’t work,” he said. “The night shift often causes extra work for the day shift.”
At peak, during the best weather, approximately 300 people are onsite. During the harsh winter months, the number has fallen to 20.
The budget, according to Judnic, isn’t quite as on-track as the work. It’s “hitting some snags. We’re not under budget, but we’re close.”
Heavy-Hitting Equipment
General Contractor Walter Toebe Construction Co. of Wixom is doing structure demolition. Subcontractors on the project include Ace Steel Erection (re-steel installation); Ajax Paving Industries (bituminous work); Atsalis Brothers (painting); Hardman Construction Inc. (sheeting); Highway Services (permanent signs); INSPEC-SOL (concrete testing); Motor City Electric; Nationwide Fence; P.K. Contracting (pavement striping); POCO (traffic control); and Wess Construction (landscaping).
Six-S Inc., from Waterford Township, is removing pavement, doing underground work, dirt work and paving. Roughly 407,984 sq. yds. (341,100 sq m) of pavement, several thousand cubic yards of concrete bridge and 2,000 tons (1,800 t) of scrap structural steel are slated for removal and recycling. To assist with the work, Toebe used a Cat 375 with a LaBounty pulverizer, a Cat 235 with a Genesis concrete pulverizer, two Komatsu PC 200s with Allied breakers and some PC 300s with concrete breakers.
Judnic said there’s too much big equipment on the job site to name.
“It’s a long list,” he said, although he insisted there’s “nothing special — just your standard heavy equipment: dozers, backhoes, loaders…” At one time there were 20 cranes on site, including several 100-ton (90 t) cranes.
The amount of equipment has posed an operational challenge for the crew because of the small footprint of the work site. Taking advantage of the compressed schedule of closure, the Detroit International Bridge Company is building a redesigned bridge plaza for improved traffic flow right “next door.”
Although it’s a separate endeavor, Judnic said the two projects connect at a strategic point, making cooperation regarding design and spatial use between the privately owned Ambassador Bridge and MDOT important. Nevertheless, Judnic said, there have been issues with traffic and scheduling.
“There’s a lot of trucks coming and going, a lot of materials being brought in…We’re trying to coordinate with the bridge company and the bridge owner, but the crews have to learn how to work around each other.
“It’s been rough,” Judnic continued. “Their agenda is different [than ours].” Because the bridge relies on traffic count to generate revenue, even the shortened closure is difficult to endure.
Challenging Work
But cramped quarters, coordination with a private bridge owner and the pressure of maintaining accessibility of a busy international border crossing aren’t the only challenges MDOT has faced on the project. The general contractor considered coordinating demolition so as not to affect reconstruction the biggest challenge.
Others believe the pedestrian bridge at Bagley Street poses more difficulties. The cable-stayed bridge will have a cast-in-place concrete pylon that will rise more than 100 ft. (30.5 m) in the air. Because it tapers on all four sides and leans in two different directions, accurate surveying is crucial.
The Gateway Project was filled with many challenging “firsts” for MDOT, the cable-stayed bridge being just one. Another unusual practice that was incorporated was the use of lime to stabilize the clay soil subgrade.
Instead of cutting 2 ft. (.6 m) deep into the ground and hauling away soil, MDOT cut 12 to 18 in. (30.5 to 45.7 cm) deep, applied lime with a spreader and used a mixer to churn the clay-lime mix.
“In Michigan, we don’t usually stabilize the ground; we cut to grade and build roads,” Judnic revealed. However, by adding lime to make the soil more granular, it provided a better working platform.
“Clay swells when it’s moist. When it’s treated, it becomes granular and isn’t as sticky. It doesn’t bind. It absorbs water and sucks up moisture.”
Judnic said drainage was increased by adding tile. By changing the character of the soil, swelling and shrinkage were reduced, which will benefit the road.
For the first time in Michigan, liquid nitrogen was used to cool concrete to 60 F. The high-strength concrete sets hot, but shouldn’t go over 180 F. When temperatures ran high, Judnic said the only way to get the job accomplished was to shock the concrete by injecting it with liquid nitrogen to drop the temperature.
By January, 165,000 cu. yds. (126,150 cu m) of concrete had been poured. Judnic recited a laundry list of other materials used on the job:
• 568,000 cu. yds. (434,260 sq m) of earth excavated (a reduced amount due to the stabilization technique used)
• 200,000 sq. yds. (167,200 sq m) of limestone
• 63 mi. (101 km) of tiling
• 3 mi. (4.8 km) of retaining walls
• 20 mi. (32 km) of high-voltage cable
• 7.6 million lbs. (3.4 million kg) of reinforced steel (for rebar)
• 9 million lbs. (4 million kg) of structural steel (for beams and girders on the new bridges)
• 46 acres (18.6 ha) of top soil and seeding
• 18,000 trees and shrubs.
In addition, 40,000 cu. yds. (30,580 cu m) of EPS blocks have been used behind the retaining walls. Consisting of dense Styrofoam, the extruded polystyrene blocks are light and inexpensive.
“They don’t have to hold up the earth,” Judnic explained. “We build concrete on top of them, but they save money.”
He noted that this is only the second major project where they’ve been used in quantity.
“We usually do this in small doses; this is huge.”
As work continues on the fourth phase, MDOT also prepares for the final two phases involving construction of approaches to the Bagley Avenue pedestrian bridge and landscaping. These smaller contracts have been structured to encourage locally owned businesses to participate in bidding.
Just as Mexicantown looks forward to being one again, commuters are eager for the reopening of the freeway and Judnic is anxious for work to be finished.
“It’s been an exhausting project.” CEG
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