The Refined Hybrid plan proposes replacing the 50-year-old elevated highway with a below-grade, six-lane, entrenched roadway running roughly north-south along the current I-345 route. The city council, along with the North Central Texas Council of Governments (NCTCOG), state that funding for the estimated $1 billion project will be acquired through federal and state sources.

TxDOT’s plan does not include funding for capping and decking portions of the proposed 65-foot-deep trench to support existing at-grade cross streets, as well as infrastructure development on top of the route and along the new surplus rights-of-way that it will create. However, it will incorporate the design into its plan when and if the City of Dallas acquires the funding. The city estimates the cost of acquisition and construction will be $370 - $430 million. 

One of the U.S. National Highway System’s shortest routes, the state-owned highway averages approximately 180,000 vehicles per day, according to TxDOT. By 2045, the agency anticipates the number growing to 206,000 – a 14% increase. The current Refined Hybrid plan adds no additional primary lanes to what the roadway currently supports.

The I-345 project is one of several major efforts addressing traffic flow through the city. The Horseshoe and SM Wright Phase I projects were recently completed. The Lower Stemmons, Southern Gateway, and SM Wright Phase II projects are currently under construction. The East Corridor and DART D2 projects are currently under study, and The Canyon Project is in its final design phase.

The resolution was approved with the addition of several amendments proposed by Deputy Mayor Pro Tem and Transportation Committee Chair Omar Narvaez. These amendments include requiring TxDOT to integrate its plan with current "city design elements, plans, and policies, including but not limited to the comprehensive environmental and climate action plan, the racial equity plan, the economic development policy, and the street design manual."

 It also requires TxDOT to update the city council at least once every six months throughout the project's design phase and reserves the city’s right to withdraw its support.

The design and environmental study phases of the plan are estimated to take up to two years, according to Assistant City Manager Robert Perez, who heads the Dallas Department of Transportation. "Should the city of Dallas change direction, TxDOT would seek reimbursement from the city of Dallas on that," he said, addressing the council.

This was confirmed by TxDOT Dallas District Engineer Ceason Clemens, who added that the next phases of the project are estimated to cost $20 million.

The debate over I-345 has been long and, at times, contentious. Neighborhood advocates, urban planners and civic leaders have argued that the highway is indicative of the city's social and economic divide, separating parts of eastern and southern Dallas from the central core. The Refined Hybrid was one of five options the council had considered which varied from doing nothing to the highway to replacing it with a boulevard system, both of which TxDOT opposed.

"We've got a once-in-a-generation chance to tear a scab off some of the most valuable parts of the city and allow it to heal into a happier, healthier, and more prosperous part of the city," said Nate Hemby of Dallas Neighborhoods for Housing, one of fourteen residents who unanimously urged the council not to support the resolution prior to the vote.

Since 2016, three studies have been produced to address issues around the highway. TxDOT's I-345 Feasibility Study was finalized in October 2022, and the council's vote moves that plan forward.

The council's approval comes after the initial voted was delayed in February 2023 and five members called for a new independent study. A public meeting was held on May 8 with city department leaders, developers, neighborhood association leaders, and other stakeholders. On Wednesday all five of the dissenting council members voted to move the plan forward, including one of its most vocal critics, District 1 representative Chad West.

"This is not a perfect solution, but at the end of the day, what we can say if we support this is that today TxDOT and the City of Dallas have decided to take down a highway, and we're going to put something better there in its place," West said.