Interstate 45 is a major interstate route through central Texas, connecting the cities of Dallas and Houston, then continuing southeast to Galveston and the Gulf of Mexico. As the primary transportation corridor between the state's two largest metropolitan areas, I-45 carries an ever-increasing volume of commuter, commercial, and heavy truck traffic. In the light of predictions of substantial population growth and accompanying traffic increases in future years, the state has a number of I-45 upgrade projects underway or in the planning stages. One essential expansion project now under construction is the I-45 Central Walker County Project in the City of Huntsville.

Huntsville, the county seat of Walker County, is the largest city between Dallas and Houston. Founded in 1835, it is one of Texas’ oldest cities and the home of Sam Houston (the first and third President of the Republic of Texas and later Governor of the state). With a population of 45,941 as of the 2020 census, Huntsville is the home of Sam Houston State University, the Texas Department of Criminal Justice, Huntsville State Park, and the HEARTS Veterans Museum of Texas.

The Texas Department of Transportation (TxDOT) I-45 Central Walker County Project aims to improve statewide connectivity. This portion of the freeway was constructed in the early 1960s, and with passenger and truck traffic having increased dramatically along the route since its construction, it no longer provides adequate traffic capacity.

As Bob Colwell, Public Information Officer with TxDOT's Bryan District, explains, “The purpose of this project is to enhance freight mobility and address congestion along the I-45 corridor, as well as locally for the citizens of Huntsville. The project will also increase safety by utilizing the latest design standards and improving the corridor's critical function as the primary hurricane and disaster evacuation route for metro Houston and Galveston.

"The Texas Demographic Center predicts that the state's population could double between now and 2050, much of which will be within the areas between Houston and Dallas. With additional people, comes additional traffic. Traffic projections from TxDOT's Transportation Planning and Programming Division indicate an increase in average daily traffic along this corridor of approximately 54 percent between 2020 and 2050. The existing roadway will not be able to accommodate the expected traffic growth. The corridor also exhibited a 56 percent crash rate increase between 2012 and 2016, and it currently exhibits peak-hour congestion that will only worsen over time without the improvements."

Widening of I-45 in Walker County has been in the works for at least a decade, its need identified on the state transportation plan for the whole route from Houston to Dallas. As Colwell relates, “The end goal is to get three lanes in each direction from Houston to Dallas. This project in Walker County started about four years ago.”

The first section of the project, which included bridges and approaches, was completed at the end of 2020. Section 2A – with an estimated total cost of $208.7 million – is currently under construction and is projected to be complete in 2023. Section 2B is in the final design stage. This segment has an estimated letting of fall 2025, with construction to begin in winter 2025. The total project is projected for completion in 2026.

The existing I-45 facility consists of a four-lane divided controlled access freeway, with two travel lanes in each direction. Segment 2A is a 4.4-mile-long project in the city limits of Huntsville from 0.3 miles north of SH 19 to 0.9 miles north of SH 30. This segment of the project will:

• Widen I‐45 from four to six lanes
• Replace existing pavement with concrete pavement
• Increase vertical clearance at main lane bridges to 19 feet
• Provide pedestrian and bicycle facilities along the urban areas of the frontage roads
• Improve drainage structures and interchanges
• Add collector‐distributor roads, which parallel and connect the main travel lanes and frontage roads or entrance ramps

The result will be six main lanes – three in each direction; four collector/distributor lanes – two in each direction; and four frontage road lanes – two in each direction. These upgrades will separate regional and local traffic and not allow them to mix and will improve traffic flow by maintaining consistent main traffic speed and allowing motorists to bypass traffic signals.

Segment 2B will be a 4.7-mile-long project from SH 30 to 0.7 miles south of FM 1696. It will include reconstruction and realignment of the main lanes and ramps; improvements to drainage structures and bridges; and improvements to frontage roads, crossroads adjacent to new ramps, and interchanges. This segment will also create two new interchanges – the first is to be for westbound SH 75 near San Jacinto Street (west of I-45) and Moffett Springs Road (east of I-45). The second will be north of the Texas Department of Criminal Justice headquarters.

Williams Brothers Construction Co. Inc. is the contractor for the design-build project; it is funded by the state's Category 4 Rural Connectivity program, which consists of an 80 percent federal and 20 percent state funding contribution.

The City of Huntsville itself will benefit greatly from the project, as City Manager Aron Kulhavy explains. “The I-45 Central Walker County Project addresses the need to move traffic efficiently through the city. The existing roadway capacity is not adequate for current or future needs. The project's completion will also make it a lot easier to access Huntsville and its businesses off the interstate. It also addresses safety concerns, in part by separating through traffic from local traffic.

“We have a fairly large commuter population, with workers and students going both north and south. Currently we see in excess of 50,000 vehicles daily along the 1-45 corridor. Population growth in Huntsville is increasing significantly. Historically, it has been around 1 percent annually, but now we 're seeing that increasing to a much higher percentage. And we have housing starts showing a growth rate much higher than in the past, with much of it people moving north from the Houston area.

“Plus, with this being the major hurricane evacuation route out of Houston, we can experience bumper-to-bumper traffic through the Huntsville area.”

As he points out, the project is not based on a traditional design model. Instead, it utilizes a collector/distributor model, which leaves the main lanes unhindered by exiting traffic. “If you want to visit Huntsville, you will get on a collector/distributor at the north or south end of town. Each major intersection will have its own exit onto a frontage road.

“This will be useful and more efficient, especially since more and more freight is moving through Huntsville. And clear spans will be greater – often parts of giant windmills are being transported along I-45. Although we can't handle too much of that now, the expansion will allow more of that type of traffic to remain on the main lanes.

“The completion of the I-45 Central Walker County Project will make it easier for all traffic to move along this major corridor,” Kulhavy continues. “It will be easier for companies to get materials to the south, more quickly and with less traffic congestion. This will make it more likely that they will establish locations in Huntsville, in order to get traffic to Houston and on to the ports.

“In addition to the long-term economic development opportunities, the project will provide short-term benefits as well – a project of this size means job creation and an infusion of money to local businesses and communities.”