The U.S. Department of Transportation has ruled that a sweeping, $136 billion transportation plan for North Texas complies with federal air quality regulations, allowing current and future transportation projects to proceed.

Some of the green-lighted projects include the Cotton Belt rail corridor, State Highway 199, LBJ East, and the Southeast Connector, a $1.2 billion three-freeway interchange in southern Tarrant County (Interstate Highway 20, IH 820 and U.S. Highway 287).

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The US Highway 380 corridor will also be studied to determine the best way to accommodate east-west travel in fast-growing Collin and Denton counties.

The Cotton Belt is a 26-mile line that would provide direct service from Plano to the DFW International Airport. Plans now call for construction on the long-awaited project to start next year and operation to begin by late 2022.

Mobility 2045: The Metropolitan Transportation Plan for North Central Texas contains $136.4 billion in transportation improvements to be made over the next 20-plus years. The Regional Transportation Council approved the plan in June 2018. The plan allocates $17.5 billion more expenditures than Mobility 2040, which the new plan replaces.

The 2019-2022 Transportation Improvement Program may also proceed, according to the Department of Transportation. The TIP is a multiyear list of projects in the Dallas-Fort Worth area approved for federal, state and local funding. The program identifies roadway and transit projects programed for construction within the next four years.

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As the metropolitan planning organization for the 12-county Dallas-Fort Worth area, the RTC develops and implements transportation projects, policies and programs designed to improve mobility and air quality.

The region's long- and short-range transportation plans must comply with federal air quality regulations because 10 Dallas-Fort Worth area counties – Collin, Dallas, Denton, Ellis, Johnson, Kaufman, Parker, Rockwall, Tarrant and Wise – are in non-attainment for ozone pollution.

Mobility 2045 takes a multi-modal approach to planning transportation projects and maintaining existing infrastructure to serve the fast-growing North Texas population.

Here’s a breakdown of planned improvements:

Freeways, tollways, arterials and HOV/managed lanes: $53.6 billion

Infrastructure maintenance: $36.8 billion

Rail and bus: $33.3 billion

Management and operations: $9.5 billion

Growth, development and land-use strategies: $3.2 billion