As traffic increases and pavement deteriorates on Interstate 10 on San Antonio’s east side, the Texas Department of Transportation (TxDOT) undertook five separate, but overlapping, projects to improve mobility and safety.

With two projects complete and three currently under construction (see “Project Breakdown”), contractors have dealt with ongoing utility relocations, traffic maintenance challenges, and special measures to mitigate the area’s poor soil conditions.

Spanning eight years – the first project started in 2016 and the final three are scheduled for completion in 2024 – the work tackles a variety of issues along the 14.5-mile stretch of I-10 East between I-410 and the Bexar County line. For instance, to meet current design standards, the first project converted frontage roads from two-way to one-way access, with turnarounds at cross street intersections. The revised traffic flow, part of TxDOT’s plan to improve the entire I-10 corridor between San Antonio and Houston, reduces conflicts between frontage road vehicles and those entering and exiting the freeway.

With traffic on I-10 expected to increase 40 percent by 2040, three of the projects expand capacity by widening I-10 East from two lanes in each direction to three, with auxiliary lanes between entrance and exit ramps and multiple ramp improvements. Mainlane reconstruction fixes the deteriorating pavement conditions caused by poor soils, heavy traffic, and rising volumes of trucks traveling through the area. To increase safety, the projects also include improvements to overpasses and intersections.

The last of the five projects under the I-10 East umbrella started in summer 2021 as the first in a series of planned improvements that will make the I-410/I-10 East interchange system safer and more efficient for the 83,000 drivers who travel through it each day.

TxDOT awarded low-bid construction contracts for the I-10 East projects to Webber, LLC, based in New Braunfels, Texas, and four San Antonio-based contractors – Texas Sterling Construction; Jordan Foster Construction, LLC; Zachry Construction; and Williams Brothers Construction Co., Inc.

Funding for the work includes $25 million from the Texas Clear Lanes initiative, $25 million from Category 4U Statewide Connectivity, and $50 million from Category 2 Metro and Urban Corridors.

The current project on the I-410/I-10 East interchange focuses primarily on the way drivers access eastbound I-10 and southbound I-410. Future planned improvements will replace the obsolete cloverleaf configuration with a five-level design that includes flyover connectors and continuous access roads through the interchange on both I-10 and I-410.

As Williams Brothers performs work for the current project, utilities continue to be relocated.

“The project schedule became a challenge since the contractor had to find work areas that weren’t affected by utilities,” said Amelia De La Garza, P.E., TxDOT Transportation Engineer.

This project also reconfigures the W.W. White intersection at I-410 to a displaced left turn intersection (DLT), also known as a continuous flow intersection. The new design relocates left-turn movements to the other side of opposing traffic flow, allowing left turns to proceed simultaneously with through movements.

“The DLT intersection is more efficient than a traditional intersection,” De La Garza said. “We selected that design to try to maintain traffic flow as much as possible in the area.”

That includes allowing for expected traffic volumes well into the future while improving local circulation.

Another of the I-10 East projects that stretches from Loop 1604 to Pfeil Road addresses issues faced by the increasing truck traffic as industrial areas expand along the freeway.

In addition to reconstructing existing I-10 East pavement and adding a mainlane in each direction, Jordan Foster Construction is raising and reconstructing I-10 bridges over Loop 1604 and reconfiguring an overpass to an underpass. Those improvements will minimize vertical clearance issues on and under the I-10 mainlanes.

The new underpass will be west of the current overpass to align with I-10 frontage road intersections, creating a straight and seamless crossing of I-10. The contractor demolished the old overpass early in the project and diverted drivers to an underpass to the east.

Because of the less-than-ideal soil conditions throughout the five I-10 East projects, “The poor soil is treated with lime to attempt to stabilize the soil and provide a solid foundation to continue the pavement section on top of it,” De La Garza said.

Rehabilitating a portion of I-410 that had large, failing sections of existing pavement required additional measures. “The plans included drilling through and injecting a high-density polyurethane foam under the existing concrete pavement to raise and fill the voids below the pavement,” De La Garza explained.

For the most part, work progresses smoothly. However, “Another challenge is the long lead time for some materials and having to schedule work around availability of those resources,” De La Garza said.

To keep traffic moving through the eight years of construction, the work plans strive to maintain two mainlanes in each direction during peak travel times. TxDOT allows temporary traffic shifts and overnight lane closures on mainlanes and frontage roads, with temporary daytime and overnight ramp closures.

Most of the time, crews work Mondays through Saturdays during the day, with nighttime work and any necessary lane closures scheduled between 9 p.m. and 5 a.m. Sunday evenings through Friday mornings. Major traffic shifts or bridge construction occasionally require weekend closures. At times, traffic detours to frontage roads.

After all the work finishes in 2024, drivers will enjoy smoother, safer travel conditions designed to continue as the area grows.

The I-10 East project in San Antonio, Texas, was divided into five separate construction contracts:

I-10 East from Foster Road to Graytown Road

Texas Sterling Construction started this $65.3 million, 6-mile project in fall 2016 and finished in fall 2020. Their work included converting frontage roads from two-way to one-way; relocating and reconfiguring entrance and exit ramps, including ramp reversals; constructing a new bridge; and improvements at five intersections.

I-10 East from I-410 to Loop 1604

Webber, LLC, started construction of this $108.9 million, 6.7-mile project in fall 2018 and finished in fall 2021. Their work included reconstruction of existing eastbound and westbound mainlanes, construction of an additional mainlane in each direction, and improvements at two intersections.

I-10 East from Loop 1604 to Pfeil Road

Jordan Foster Construction, LLC, started construction of this $90 million, 2.8-mile project in early 2020 and expects to finish in summer 2024. Their work includes reconstruction of existing eastbound and westbound mainlanes; construction of an additional mainlane in each direction; reconfiguration of an overpass to an underpass; raising and reconstructing I-10 bridges over Loop 1604; and improvements to an intersection, frontage roads, and ramps, including ramp reversals.

I-10 East from Pfeil Road to the Bexar County Line

Zachry Construction started this 5-mile, $149 million project in late 2020 and expects to finish in summer 2024. Their work includes reconstruction of existing eastbound and westbound mainlanes; construction of an additional mainlane in each direction; and improvements to frontage roads and ramps, including ramp reversals.

I-410/I-10 East Interchange

Williams Brothers Construction Co., Inc., started construction of this $100 million project in summer 2021 and expects to finish in fall 2024. Their work includes construction of two direct connector ramps from northbound I-410 to eastbound I-10 and from westbound I-10 to southbound I-410, as well as I-410 pavement improvements.

• Owner – Texas Department of Transportation; Timothy Parker, P.E., Area Engineer; Amelia De La Garza, P.E., Transportation Engineer; Arif Chowdry, P.E., Project Manager
• Construction Engineering and Inspection – Raba Kistner, Inc., San Antonio, Texas; Howard Holland, P.E., Project Manager; Jacob Fuentes, P.E., Resident Engineer
• Contractors – Texas Sterling Construction, San Antonio, Texas; Webber, LLC, New Braunfels, Texas; Jordan Foster Construction, LLC, San Antonio, Texas; Zachry Construction, San Antonio, Texas; Williams Brothers Construction Co., Inc., San Antonio, Texas

Construction of the five I-10 East projects requires:

• 47,000 cubic yards of structural concrete
• 556,000 square feet of bridge decks
• 2.6 million pounds of structural steel
• Nearly 73,000 linear feet of prestressed concrete girders