After years of often heated debate over whether to renovate the downtown River Center Branch Library or build anew, the walls of the building will finally be coming down this fall.

Library system officials have set October 4 as the official date to demolish the library branch at the corner of St. Louis Street and North Boulevard to clear the way for a new, expanded library branch building to open in about two years.

The nearly four-decade old River Center Branch will be open for one more day, on Tuesday, after which it will be closed to the public.

The building is already mostly empty, and librarians expect to remove the final volumes by July 10. Staff plans to move into a temporary site at 447 Third Street by mid-July, according to assistant library director Mary Stein. The exact day will depend on how soon they can wire the site for electronics.

The old library was built in the 1970s, and crews will spend several weeks removing asbestos before the tear-down can begin in earnest.

“Demolition must be planned very carefully since we are surrounded by historical buildings such as the Old State Capitol as well as important civic buildings and spaces; we also have the issue of vehicular access for the two courthouses and governmental building,” Stein wrote in an email.

There will be a meeting to discuss demolition and construction in August, but officials do not currently expect to block any roads while replacing the River Center Branch, except as needed to make deliveries and move equipment, Stein said.

That equipment won’t include explosives, or even a wrecking ball, though. Crews believe they can demolish the old brutalist-style building with smaller vehicles.

Construction of the new, 50,000 square-foot building is expected to last until spring of 2018, but it will take a few more months to finish the interior for a final completion date in late August of 2018, Stein said. The demolition and construction are budgeted to cost $19 million.

Follow Steve Hardy on Twitter, @SteveRHardy.

Follow Steve Hardy on Twitter, @SteveRHardy.