Sugar Land's Mega Road-Rail-Bridge Project Bolsters Economic Opportunities
The city of Sugar Land, one of Texas' fastest-growing cities, is on the homestretch of completing a new four-lane, divided connecter that will extend University Boulevard from northbound U.S. Highway 90A to Stadium Drive.
The design and construction of the half-mile-long University Boulevard Extension Project is part of the city's 2012 Master Thoroughfare Plan. Once built, this north-south corridor will build upon previous efforts to enhance access from the northern section of this Greater Houston area suburb to just south of U.S. 90A.
The project also includes a key roadway crossing over the Union Pacific Railroad (UPRR) and rail relocation, along with a new bridge that will improve mobility and provide access into a growing residential/retail area within the Imperial Sugar district near Constellation Field, the city's minor league baseball stadium, and Nalco Champion's expanding headquarters campus.
Construction activities commenced in August 2015 and the first and second work packages, road and rail, have been completed. Construction of the new railroad and creek overpass represents the final phase of construction, which is anticipated to wrap up in February 2018.
A Broad Construction Scope
The University Boulevard Extension Project is divided into three separate work packages: roadway, rail and bridge. This complex design-bid-build venture will cost approximately $21 million and directly affects a variety of stakeholders, including the Texas Department of Transportation (TxDOT), the Federal Railroad Administration, UPRR, Nalco, and Johnson Development Corp. (JDC), a residential and commercial land development company headquartered in Houston. This city-owned initiative is not receiving any state or federal funding.
The construction scope includes a grade-separated overpass at the UPRR spur crossing at Oyster Creek, a shared-use path and sidewalk (with a custom-steel pedestrian rail on the outside and a modified T131RC rail on the inside for aesthetics), nearly 25,000 square feet of retaining walls, and a bridge-supported waterline. At the rail crossing, a new traffic signal preemption system will increase safety by clearing vehicles from the path of oncoming trains.
Engineering firm Lockwood, Andrews & Newnam Inc. (LAN) is performing the bulk of design and construction administration services. Harper Brothers Construction (HBC) and Webber LLC are the general contractors spearheading construction. HBC is overseeing bridge and roadway construction and Webber handled the rail relocation efforts.
Strategic Negotiations, Win-Win Results
Even though development efforts only extend half a mile, the project team has had to contend with a marathon of logistics and engineering dilemmas. One such obstacle revolved around building an at-grade crossing at the south end of the project. Normally, UPRR requires the closure of three existing crossings when a new at-grade crossing is requested.
"We were able to negotiate with UPRR the closure of just two crossings, at Nalco's private drive and at a public crossing at Wood Street. In turn, they were given the rights to a right-of-way that they needed for a new double-track section," says Sugar Land Assistant City Manager Christopher Steubing, P.E.
Back in 2012, UPRR announced plans to construct a double-track section along its existing rail line. The proposed double-track section will be located along U.S. 90A, between SH 99 (Grand Parkway) and U.S. 59 at the city of Stafford border. These construction efforts will affect several major crossings within Sugar Land, including Eldridge Parkway and Dairy Ashford Road, where grade-separations have been researched in the past, as well as potential future crossings.
Bridging Project Challenges
Currently, crews are building a 510-foot-long, grade-separated railroad and creek overpass comprised of 560 cubic yards of reinforced concrete bent and abutment substructure elements with 4,000 linear feet of drilled shaft foundations. The bridge deck spans 34,000 square feet, with 4,500 linear feet of Tx54 girders being constructed using a non-standard strand pattern with harped strands. Temporary coffer dams are being used to allow crews to construct the bridge columns at the edges of Oyster Creek. A new retaining wall, utility installation and relocation, and roadway approaches and drainage work are also included in this final construction phase.
The project team faced several unique challenges in constructing the flyover and retaining wall. Geotechnical investigations revealed that existing soils - ranging from silty sand to fatty clays - were mostly cohesionless in structure. LAN determined that the soil profile combined with the 25-foot-tall embankment was very high-risk due to the inadequate bearing capacity of the in-situ soils. Also, record amounts of rainfall in recent years have exacerbated poor soil conditions throughout all stages of the project.
LAN was tasked with devising a plan to improve foundational stability. Engineers proposed two options: a conventional cement-stabilized sand method that would have required the replacement of up to 8 feet of soil, or a rigid inclusion ground improvement technique. Ultimately, the city approved the rigid inclusion solution.
Hayward Baker Inc. was contracted to place nearly 2,000, 12-inch-diameter rigid inclusion grout columns beneath the 30,000-square-foot embankment area. Without these rigid inclusions, the resulting settlement was projected to be about 5 inches, says LAN Project Manager Lauren Van Andel. "This innovative method was deemed the best long-term maintenance solution for the city versus just removing and replacing soil to improve the foundation," she notes.
Compared to conventional pile foundation systems, rigid inclusions are a sustainable, cost-effective solution that transfers loads from foundations comprised of soft, compressible soils to lower-bearing stratums containing more rigid materials, such as dense sand, stiff clay or glacial till. This method is also advantageous because it reduces waste generation and associated disposal requirements and costs. Performance-wise, rigid inclusion technology is comparable to that of deep-pile foundations but offers additional cost and schedule savings because workers do not have to drive lengthy steel piles into the bedrock.
Another complication involved constructing an aerial water transmission line on the new bridge versus boring underground, which would have been more expensive. "The aerial water line itself is not atypical - we carry water lines on bridges all the time. However, for safety reasons Union Pacific discourages placing any utilities over their rail tracks," says Van Andel.
The rail company granted the team permission to install the 12-inch-diameter water line (which will extend approximately 1,600 linear feet) on the bridge, but required that all pipe over the right-of-way be enclosed with steel casing to prevent water from spilling onto the tracks in the event of a leak. Steel pipe was used within the retaining wall embankment and PVC pipe was used in areas extending outside of the bridge.
The bridge's structural design does not allow for placement of the water line on top of or alongside the overpass. Engineers came up with another out-of-the-box solution by designing special hangars and rollers between the Tx54 girders to house the pressurized water transmission line.
The bridge's aesthetics align with the design of the entire development site, which includes two existing bridges that JDC constructed a few years ago, says Keisha Seals, the city's Project Manager. "This new structure will be viewed as one of the gateways into the Imperial Redevelopment District. We wanted to make sure that the whole corridor has a similar feel." Red brick and white precast elements characterize many of the public structures found within the 720-acre Imperial master-planned community, which is primed to become an upscale shopping, dining, entertainment and cultural destination.
A Sweet Place to Live, Play and Work
In a community flush with economic opportunities, the University Boulevard Extension Project benefits Sugar Land's businesses and citizens in more ways than one.
"Any time that we can enhance north-south mobility is critical for us," says Steubing. "Also, our baseball stadium is a destination venue, just like our new concert venue that opened early this year. Finding ways to help people reach those venues so that they can enjoy their time while they're in our community is key to us."
Seals elaborates further: "Traffic is a number one concern of any resident living anywhere. This initiative will ensure that our mobility stands out against the rest, and that our residents are happy to live, work and play in this city."
Sugar Land, home to the historic Imperial Sugar Co. headquarters, started out as a sugar plantation in the mid-1800s. Today, this award-winning community has a population estimated at around 88,000 and is consistently recognized as one of America's best places to live and work. It has achieved a sustainable, strong local economy through aggressive economic development programs focused on creating new wealth and jobs. Numerous master-planned residential communities have been established here. As a regional employment center with nearly 26 million square feet of commercial space, Sugar Land also is the center stage for many high-profile corporations, including Minute Maid, UnitedHealthcare, Aetna, Texas Instruments, Schlumberger, Fluor Corp., Noble Drilling Services and Tramontina USA.
Steubing concludes: "Any time we can push a project forward that advances the community, both in a localized way as well as in a regional sense, those are primary projects for us. It's something we take into regard with our council goals and objectives, and the vision of the city, as we move every project forward."