Proposals for the new Fourth Corso viaduct include block walls to shorten the bridge's length.
A technique known as mechanically stabilized earth, MSE, is proposed to build walls on the east side of the bridge from Fourth Street west to the Union Pacific Railroad crossing.
Dan Giittinger, public properties director, said the proposal would shorten the 800-foot bridge by 300 feet.
It would also change the appearance of the bridge. Its highest point now is over Third Street, but the new bridge would rise highest above the railroad tracks. The changes are not expected to affect the slope on either end of the bridge, but the MSE walls require a wider bridge on the east end.
The driving surface itself would have three lanes.
Giittinger said the designs at this point are preliminary and the city will be scheduling public hearings to get public input at the early planning stages.
"There will be no specifics at the meeting because there is no specific plan yet, but the public hearing is an opportunity to hear the public's ideas," he said.
The city is in the permit process for replacing the viaduct, which was built in 1959.
Giittinger said the structure of the bridge is still solid, but its sidewalk, railings, deck and concrete surface are not sufficient. "They are beyond their useful life and they will only continue to degrade," he said.
Contributing to the design is the bridge's relatively high use by trucks.