More street changes are in the works for downtown Austin as construction ramps up on the Capitol Complex Master Plan. On Wednesday, the Austin Transportation Department converted 17th and 18th streets between San Jacinto and Trinity into two-way streets.

Texas Facilities Commission spokesperson Francoise Luca says two-way traffic is also planned for streets on the other side of Congress Avenue.

“We will do the same on the west side of the Capitol Complex between Colorado and Guadalupe Streets," she said. "That will happen later this summer, probably close to the beginning of August.”

Phase 1 of the master plan will transform North Congress Avenue between Martin Luther King Jr. Boulevard and 16th Street into a grassy pedestrian mall with underground parking.

Luca said 17th Street will eventually become a primary east/west corridor for traffic.

“17th Street will be a key street for us, because that will be the entrance to the underground parking that will exist underneath what today is Congress and what is currently being excavated,” she said.

The plan also includes two new state office buildings bordering the 4-acre pedestrian mall. Luca said excavation work has finished on what will be the 14-story George H. W. Bush State Office Building, at 1801 Congress Ave.

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“Our contractor is drilling piers for the [foundation] structure of the building. So, you will see the building start to come up," she said. Cranes will likely start to appear next month, she said.

Once construction is complete, cars will be able to cross the pedestrian mall only at Martin Luther King Jr. Boulevard, 17th and 15th streets. Phase 1 of the plan is expected to cost $581 million and finish by May 2022.