Memphis International (MEM) is embarking on an ambitious, multi-faceted plan to right-size its passenger terminal for a better fit with present and future traffic. The current priority, however, is airside enhancements.
The Tennessee airport is nearing completion of an estimated $90 million of apron and airfield infrastructure improvements. In addition to replacing aprons that were built during the 1960s and 1970s, crews are upgrading the airport's stormwater management system.
The apron reconstruction was undertaken in three phases with approximately 75% of it funded by the FAA grant.
Project: Apron Improvement
Location: Memphis International Airport
Primary Elements: Extensive upgrade of airside aprons.
Approx. Cost: $90 million
Funding: FAA (75%); airport fees 25%
Engineering & Design: Pickering, Memphis
Trench Drainage Systems: EJ, coordinated by Tennessee Branch Office
Project Management: APAC, Tennessee
Installation: GCM, Inc., local subcontractor
Rolling With the Punches
A few years ago, MEM was "de-hubbed" by Delta Air Lines, ending a long run of connecting flight operations that at one time included Northwest and Republic airlines (neither of which still exists in the same state). Most of the airport's connecting flights are now gone, leaving a core market of passengers traveling to or from Memphis. While airport officials don't expect another carrier to locate its hub at MEM, they note that the facility has ample capacity to accommodate one.
As a direct response to the de-hubbing, the airport is undertaking a $114 million renovation of Concourse B. The project is designed to shrink and modernize the facility while also improving the experience customers have when using it. The plan includes closing one-fourth of the concourse's existing gates and significantly upgrading much of what remains. The plan will consolidate nearly all of MEM's passenger flights into refurbished and expanded gates in Concourse B, and "mothball" remaining gates in the airport's other two terminals. Ticket lobbies will remain largely untouched.
The front of the airport won't change during this phase, but the 1964 vintage Concourse B will. The Y-shaped facility will double in width, gain moving walkways and receive an infusion of natural light. The sweeping project began with demolition of the south end of Concourse A and is scheduled to wrap up in 2020 or 2021.
Former Airport Authority Chairman Jack Sammons and Scott Brockman, current president and chief executive officer of the authority, stand ready to answer critics on both sides: those who question the decision to tear down facilities that are already paid for and those who wonder why more money is being spent on an airport that has seemingly been in a nosedive since Delta started cutting flights three years ago.
"This is a giant step forward for the future of our region," asserts Sammons. "We think this is the highest and best use of our investment."
Sammons recalls being more than a bit skeptical when he first heard about the plan to tear down some gates and modernize others. Then, strong positive response support for the strategy from MEM's carrier changed his mind. "There is dynamic change here, but we are offering an enriched experience for our visitors," he relates. "The modernization project is designed to make the airport functional and competitive at least 20 years down the road. It has been endorsed by all passenger airlines serving the airport, and airport board members were briefed individually."
Sammons considers the modernization plan a "major bet" that MEM will rebound from the devastating blow it received from Delta, and that an upgraded facility will be a selling point to attract more flight operations as a non-hub location. "It will answer perennial complaints about a dated, cramped experience for passengers resulting from narrow aisles, low ceilings and small holding rooms at the gates," he adds.
Demolishing about 20 gates on the southward extensions of concourses A and C is expected to alleviate bottlenecks that prevent competing airlines from easily sharing Concourse B.
After demolition, the airport will retain about 40 gates in the B concourse for arriving and departing passengers. Areas slated for demolition include MEM's most recent addition, an expansion of 16 gates in Concourse A that was completed in 2000. The project was specifically designed to accommodate 50-seat regional jets, which were popular at the time. Since the project, many regional jets have been grounded by Delta and other airlines because of elevated jet fuel prices and efficiency issues.
MEM's current traffic of about 2 million passengers per year requires 22 gates, note airport officials.
Most of the construction for the modernization project will occur on the concourse side of the airport's security checkpoints. Ticket lobbies will initially be left as is, Concourse A security checkpoint would be closed, and baggage claim for all arriving flights will be consolidated in Terminal B.
"We're going to turn Memphis International into a modern terminal for airlines to operate out of," advises Brockman, who assumed the role of president and chief executive officer in January. "It will be a game-changing experience, and we currently expect to walk away from this project with no more debt than we have today."
Brockman describes the renovations now in progress as the kickoff for reinventing MEM. "Part of that reinvention involves consolidating operations so we can better serve our passengers, airlines, concessionaires and employees," he explains. "More importantly, we're going to modernize the B concourse, giving our passengers way more convenience."
Plans include consolidating all airline offices and concessions into Concourse B, in addition to adding moving walkways, widening corridors and expanding boarding areas. The project will also remove the entire south ends of concourses A and C to allow larger aircraft unobstructed access to gates in the updated B concourse.
Eventually, all of MEM's current airlines will join Delta in Concourse B - Southwest Airlines, American Airlines/US Airways, United Airlines, OneJet, Allegiant Air, SeaPort Airlines and Frontier Airlines. With more than 60 updated gates, the reconfigured B concourse is designed to accommodate more than 300 flights a day, the airport's high-water mark from more than a decade ago, and more than triple the current traffic of less than 100 flights a day.
Before MEM can begin modernizing its passenger terminals, it must first complete a major airside project currently underway. Crews are replacing aprons outside the gates for arriving and departing aircraft on all sides of Concourse B. Many were four and five decades old.
During the three-phase project, workers have removed and replaced about 320,000 square yards of concrete around the perimeter of the concourse.
A new stormwater management system is another major component of MEM's airside infrastructure improvements. Pickering, a firm based in Memphis, provided design engineering for the project, and APAC-Tennessee served as the
onsite construction manager. GCM, a local subcontractor, installed the new stormwater management system.
The project required about 10,000 feet of linear trench drain assemblies, which were supplied by EJ. After the airport's consulting engineers finished the apron design plans, construction of the trench drainage began in 2012. Crews are expected to complete the final phase of the project this December.
Given the 50 to 60 inches of precipitation Memphis typically receives each year, what happens to rain after it falls is an important issue at MEM. The airport's stormwater drainage system is a gravity flow system (without pumping stations) that flows into Nonconnah Creek, just 1/4 mile north of the airport. The creek flows west for approximately six miles into McKellar Lake, which is part of the Mississippi River.
The specifications for MEM's current project reference the airport authority's Comprehensive Storm Water Pollution Prevention Plan, administered by government agencies such as the Tennessee Department of Environment and Conservation.
One significant aspect of the apron reconstruction is that the trench drainage components used for the project are designed to contain or manage fuel spills as well as facilitate stormwater management. The airport consulting engineers configured a series of concrete firestops between each trench, and the sluice gates can be remotely opened and closed to prevent fuel from flowing into storm drains in the event of a spill. After workers removed massive amounts of existing apron concrete, contractors built a 2-foot wide, 4-foot deep reinforced concrete trench structure.
On top of the trench, crews positioned EJ 6908 top flange trench grate bolted assemblies in line to be poured integrally with the structure. The trench system was poured in place about 10 linear feet at a time. "EJ has provided quality products for this project, and was very helpful and responsive to any requests that we have had," says Walter Pearson, a project manager for APAC-Tennessee.
The products allow for slight but continuous elevation changes during construction of the trench system, adds Lee Veldboom, EJ's technical engineering manager. Because the drainage grate assemblies are placed in 2-foot increments, their position can be continually realigned during installation to allow the trench system to follow the designed contours of the apron area. Alternative pre-formed trench components were reviewed and rejected during a product evaluation period because they weren't capable of easy elevation changes during construction.
Mike Morganthaler, a project manager with APAC-Tennessee during the work at MEM, appreciated EJ's support when the team realized that one of the specified end-piece frame components wouldn't be needed. "As our contractor began installation of the trench grates and observed some potential concrete forming issues, EJ worked with us to delete the end frames from shipment quantities and was a resource providing guidance or troubleshooting to help us adjust our method of installing each drainage assembly."
Engineers from Pickering designed the drainage system, including the trench drain system, and specified aircraft-rated frames and grates. "The contractor selected a product according to the specifications, and we reviewed the submittals for compliance," says Patrick Neal, principal/transportation project manager at Pickering.
The trench grate assemblies used at MEM are load rated by EJ as Airport Extra Heavy Duty using a testing method outlined in AASHTO (American Association of State Highway Transportation Officials) specification M306. The specification requires castings intended for H-20 traffic to hold a 40,000-pound proof load for one minute applied on a 9-inch square footprint in the center of the casting. For airport-rated products, EJ ups the load to 200,000 pounds to boost safety for end-users. Products that pass the more demanding load test receive the Airport Extra Heavy Duty Rating.
The linear trench drain assemblies from EJ feature a top-flange design to enhance the load bearing capabilities of the trench system. The design provides a better interface with the concrete structure by the flange protecting the structure's edges, which helps prevent structural failure beneath the trench frame, explains Veldboom.
Additionally, the assemblies include vertical gussets with openings positioned so crews can run rebar through the top flange frame and tie the unit into the reinforcing steel. The holes are also designed for bolting adjacent trench grate products together.
Frames using pockets for insertion of a replaceable threaded nut are another desirable feature, says Veldboom. "In the event that a drill and tapped location becomes stripped or cross threaded during construction/maintenance, the location can be easily retrofitted using a standard nut," he explains. "Prior to introduction of this innovative EON LOCK(r) feature by EJ, all bolting locations were simply drill and tapped, which was difficult to repair after construction. In addition, there are vent slots in the top of each trench frame. During construction, the vent slot allows air to escape while concrete is being poured and provides a visual check for inspectors to verify whether concrete has flowed completely under the trench frame."
EJ also provided airport-rated hatch assemblies designed to provide operations personnel access to the system's sluice gates. The 30-inch-square hinged hatches are located between sections of trench drain and corresponding storm drain inlets. They are frequently used in other applications with below-grade fire hydrants.
In retrospect, APAC is pleased with the EJ 8196 model hatch assemblies as an access solution for the sluice gates. Team members describe them as ideal, in part because they have the same design load rating as the trench grates (Airport Extra Heavy Duty) and similar flush mount profile.
|Did You Know?
According to the Memphis-Shelby County Airport Authority, Memphis International Airport (MEM) is the centerpiece of the first true aerotropolis in the United States. Just as a metropolis includes suburbs branching out from a core city, an aerotropolis is built around an airport, with strings and clusters of airport-related businesses radiating from it.
MEM currently enplanes about 2 million passengers annually and is also one of the world's busiest cargo airports. Until a few years ago, it was the top cargo airport, serving as the primary "Super Hub" for FedEx Express. Today, MEM ranks a close second to Hong Kong International Airport in cargo.
The Tennessee airport encompasses 5,100 acres, with the airfield occupying about 40% of its total land. With four runways (three north-south parallel runways and one east-west runway), MEM is also home to the 164th Airlift Wing of the Tennessee Air National Guard, which operates C-17 Globemaster aircraft.
Last year, MEM's total net assets were $686 million.