A Nov. 20 proposal to add an additional flyover to the US 183 and MoPac interchange in North Austin could result in time savings of around 30%-40% but could cost around $50 million.

Central Texas Regional Mobility Authority staffers pitched this proposal Nov. 20 after the board of directors had authorized the agency to issue a request for detailed construction proposals. The project is slated to start construction in early 2021, and the board anticipates approving a construction contract in May.

The agency is overseeing the US 183 North toll project, which is planned to add two express toll lanes in each direction to US 183 between MoPac and SH 45 North near Cedar Park. The toll lanes will also connect to the MoPac express toll lanes.

CTRMA Engineering Director Justin Word said staffers have been looking at better ways to connect the southbound US 183 toll lanes to southbound MoPac and to provide drivers with more options to exit the toll lanes.

The proposed flyover would allow drivers in the southbound express lanes to exit sooner and to access the MoPac frontage road and get to Spicewood Springs Road, Far West Boulevard or RM 2222. Word said the existing plan allows drivers in the toll lanes to exit the MoPac toll lanes and exit to RM 2222, but to do so, drivers would have to cross three lanes of traffic in a relatively short amount of time.


“This option will allow those folks who want to access 2222 to get on the correct side of the road,” he said. “They can take this and access those exits without having to do that weave.”

The cost for the new flyover is about $50 million, but the agency is increasing the estimated cost of the project to $580 million, up from $500 million. Word said CTRMA has already used contingency funds while the project faced delays, and the additional funds would recapture some of that. The Texas Department of Transportation is funding the addition of a fourth continuous nontolled lane in each direction for about $105 million.

“Our findings show in the 3%-4% net increase in toll revenue for the project, which helped offset the cost and make it toll-viable,” Word said.

In late 2017, Gov. Greg Abbott and other state leaders announced that no funding from Propositions 1 and 7, both of which allocated more funding toward transportation, could be used on projects with tolled elements. That led to a statewide freeze on several projects, including US 183 North.


In January, the agency received approval from the Texas Transportation Commission, the governing body of TxDOT, approved a new agreement with CTRMA to allow the project to proceed.