Construction is expected to be complete in October on the city's first protected bicycle lanes.
The Chattanooga Transportation Department is narrowing Broad Street from six to four lanes. Existing on-street parking spaces will be separated from the road with a curb, and one lane of traffic on each side will be converted to on-street spaces.
The protected bike lanes stretch from the Tennessee Aquarium to Martin Luther King Boulevard. The Transportation Department said the street improvements will help increase foot traffic, downtown retail and overall safety.
Four lanes on Broad Street will still be able to accommodate the daily average traffic of 8,000 vehicles, Transportation Administrator Blythe Bailey said.
"We're basically taking the road and getting more use out of it without a negative impact on traffic," he said.
The $225,000 project will create a "more vibrant streetscape" for pedestrians and bicyclists, Bailey said. The city has received two federal grants to create a bicycling network from downtown to surrounding neighborhoods. The project coincides with a White House challenge to make streets safer for cars, bikes and pedestrians.