Since SER Construction Partners LLC began work on the Texas Department of Transportation's (TxDOT) $71.33 million U.S. 90 Interchange at Greens Bayou project in Houston (northern Harris County) in August 2024, crews have completed more than 40 percent of the project.
Construction remains on target for a December 2027 delivery date.
Crews are constructing two sections of U.S. 90 that include three travel lanes in each direction with median barriers and paved shoulders adjacent to the interior and exterior lanes with a bridge over Greens Bayou. There's also an overpass at Purple Sage Road with sections of elevated approach roadway supported by nearly 9,000 linear ft. of mechanically stabilized earth-retaining walls (MSE).
SER Construction Partners LLC photo
The work zone covers 0.41 mi. of Purple Sage Road.
"U.S. Highway 90 is a major east-west highway in the southern United States that traverses the city of Houston and the greater Houston area," said Scott Ashmore, SER Construction's senior project manager, "and this will complete the only two sections of the freeway inside Beltway 8 that have not been built to full freeway standards."
AECOM designed the project.
"Prior to the start of construction, there were significant concerns regarding settlement analysis information provided in the project's geotechnical engineering report," Ashmore said. "As a result, TxDOT's project design firm AECOM amended the project plans to prescribe additional ground improvements in those areas intended to have the greatest height of embankment placed atop the existing soils.
"In total, greater than 150,000 cubic yards of unsuitable soils are being exported from the project and nearly 160,000 cubic yards of earthen embankment and nearly 160,000 cubic yards of cement stabilized backfill — for a total of 320,000 cubic yards of materials — are being imported for incorporation into the project from offsite source locations. The cement-stabilized backfill material [cement sand] is being produced by one of two SER onsite pugmill facilities."
As the existing main lanes were demolished to create the construction zone, traffic was switched to the frontage roads on either side of the highway. SER Construction built temporary lanes on both ends of the work zone.
Progress Continues
Considerable progress has been made, Ashmore said.
SER Construction Partners LLC photo
All the substructure work is complete at the Greens Bayou bridge site — drill shaft foundations; columns with caps and abutments; including backwalls and wingwalls; and structural excavation required for the foundation.
Improvements at either side of the Purple Sage Road bridge site are mostly complete.
Ongoing work includes placing CSBE for MSE wall foundation improvements; beginning MSE wall work at walls C and D, which is east of the Purple Sage Road bridge site; realigning the existing MUD 421 waterline realignment, which will allow for the work to resume on the Purple Sage Road bridge, specifically Bent #3; and the importing and placement of embankment in the project's fill sections.
"Substructure components of the Greens Bayou bridge structure were sized for dimensions such that the construction was to conform to TxDOT's standard specification for mass concrete requirements," Ashmore said. "An engineered thermal control plan was developed, and among the measures employed were a specially designed concrete mix formula, a heat retention insulation system and electronic continuous temperature monitoring system devices embedded in each concrete pour."
In mid-November, drill shaft foundation work resumed on Bent #3 at the Purple Sage Road bridge and, in December, the erection process for the 220-ft.-long steel girder span at Greens Bayou (Span 4) was initiated.
The project includes the construction of more than 80,000 sq. yds. of mostly 14-in. thick continuously reinforced concrete pavement. The project's concrete pavement will be constructed by SER's fleet of GOMACO equipment, including a GP-2600 paver, a PS-2600 placer/spreader and a T/C-600 texture/cure machine.
SER Construction Partners LLC photo
No existing lanes are being removed during the project.
The Purple Sage Road bridge will be a three-span structure supported by 84-in. diameter drill shafts, specialty flared "tree" columns and TX46 prestressed concrete girders. The bridge will be 134.5 ft. wide.
"Specialty forms have been rented from EFCO Corp. to assist with the concrete formwork of the flared tree columns and the inverted tee bent caps that are a part of the bridge's substructure," Ashmore said. "To date, all drill shaft foundations have been installed, and both of the bridge abutments have been cast in place, as have the intermediate bent's support columns. This bridge is expected to be completed before summer 2026."
Offsite Work Part of Project
Prestressed concrete girders, precast concrete bridge deck panels and precast concrete MSE wall panels are fabricated by offsite material producers, then shipped to the site for installation. A GOMACO C-450 will be used to finish the bridge deck.
The Greens Bayou bridge is a five-span bridge, with span 4 being a 220-ft.-long span over the bayou.
"Span 4 is over water and is supported by 15 220-foot-long plate steel girders," Ashmore said. "This bridge is expected to be completed before summer 2026. [We're using] a combination of prestressed concrete girders, field spliced steel plate girders and precast concrete MSE wall panels fabricated by offsite material producers that are shipped to the site for installation."
SER Construction Partners LLC photo
Crews are engaged in earthwork, site prep and drilling operations, which transitioned into the erection of concrete pillars and prefabricated concrete elements; those were delivered on site as needed and placed.
Equipment-wise, operators are using multiple Cat models, including large excavators, dozers, loaders and other standard pieces of iron. There are several crawler cranes on site, including Mantiwoc 2250s.
SER Construction's management team includes a senior project manager, a project manager, a project superintendent, a bridge superintendent, an earthwork superintendent and a variety of foremen.
On a typical day, SER will have upward of 30 employees on site.
The primary subcontractors to date are HB Farmer Foundation, which is performing drill shaft installations, and Choctaw Erectors, which is erecting the steel plate girders for the Greens Bayou bridge.
SER Construction owns a large fleet. This project is putting it to the test.
"To date, the main wear and tear issues seem to have been associated with the production of cement-stabilized backfill [sand] using the onsite Rapidmix 400C and Davis/Pugmill System 750," Ashmore said. "SER conveniently has a permanent shop facility 15 miles from the project site, which affords SER maintenance staff a quick response time. Daily fueling and routine servicing are performed by SER personnel."
Houston-based Mustang Caterpillar is a key equipment provider to SER.
"Mustang Cat has been utilized to supplement SER's fleet with rental equipment, when necessary," Ashmore said. "Rented Caterpillar 725 off-road trucks are being utilized to haul the 150,000-plus cubic yards of material stabilized at the onsite pugmills to the point of placement within the embanked MSE wall sections being constructed." CEG
