If the Texas Department of Transportation gets its way, the portion of I-30 that runs through downtown Dallas will be double the size it is now, spanning a total of six lanes in either direction.

TxDOT shared its initial design schematics at an open house-style meeting on October 29 at the Omni Dallas Hotel — the first time the public was able to see details of the expansion such as frontage road locations, exit ramps, street bridges, and surrounding real estate.

The $300-million project would begin at Hotel Street by the Dallas Convention Center and extend east to the I-345 interchange, roughly 2 miles.

The proposal calls for a total of six lanes in each direction, plus two feeder lanes. The highway will be reconstructed as a canyon similar to the design of Woodall Rodgers Freeway. It will be below grade from the convention center to Cesar Chavez near I-345.

"This plan maintains the street grid, reclaims right of way to maximize development potential and, accommodate multi-modal transportation options across I-30," City of Dallas Transportation Director Michael Rogers said in a presentation. "This plan incorporates all of the 'Guiding Principles' the City Council adopted in January."

The reconstructed I-30 will have only three exits eastbound and westbound for downtown:

• Cesar Chavez
• Griffin Street
• a small exit near the convention center

That takes away exits for Ervay and Lamar Streets. Frontage roads would only be located on portions of the highway.

Cadiz Street is primed to have the biggest transformation. It will be reconstructed as a boulevard-style street with bike lanes and 10-foot wide sidewalks. Cadiz will not cross any frontage roads in the proposed design even as it intersects I-30. It would follow its current alignment, but dip down on the east to dead-end into the frontage road.

The westbound frontage road for the Cesar Chavez exit would join two-way traffic on Cadiz when the frontage reaches Harwood.

A new bridge will extend Browder Street reconnecting the road dissected by I-30 and will intersect Cadiz at I-30.

There are three deck parks and plazas planned as part of the reconstruction, but those are completely unfunded.

"It's possible that if funding will become available, the deck plazas would be constructed with I-30 canyon project," said City of Dallas Chief Planning Officer Peter Chacko. "Even if funding is not immediately available, the city will continue to work with TxDOT to accommodate future deck plazas."

The design plans do not include considerations for the future I-345, the elevated freeway dividing downtown from Deep Ellum that some are rallying to remove.

"This schematic you see today leaves every single option for I-345 still on the table," Rogers said.

Environmental impact plans need to be approved in 2020, clearing the way for the final design phase. The project is funded via TxDOT's Unified Transportation Plan.

The canyon project is just the first of six phases to renovate I-30 and US-80 between Dallas and Rockwall and Forney. Phase two would continue east on I-30 to Loop 12/Buckner Road. The third phase would extend from Loop 12 to I-635. Segment four runs to Lake Ray Hubbard at Bass Pro Drive. Segments five and six would reconstruct US-80 from I-30 to Forney.

The total project cost is $1.98 billion.

The meeting represented the opening of a public comment period, which will end on November 13. Written comments can be emailed to Ashton.Strong@txdot.gov.