The long-awaited Publix Super Markets Inc. store in the Channel district is moving forward.

Mercury Advisors, developer of the grocery store and a 21-story apartment tower on the same vacant block in between Madison and Twiggs streets, on Monday received preliminary approval for its plans from the city.

"We received approval on the foundation and shell for the Publix grocery store at Channel Club," Mercury principal Ken Stoltenberg wrote in an email Tuesday, "and we filed the foundation, shell and finish permit for the tower portion of Channel Club. Our expectation is to finalize this transaction in March and then commence with construction."

Channel Club will consist of a 37,600-square-foot Publix store with rooftop parking and a 21-story, 323-unit apartment tower. The tower will break ground first; once it tops out, Mercury will begin construction on Publix. They will wrap up concurrently in 2017.

When the Publix is complete, it will be a watershed moment for downtown Tampa, cementing the urban core's status as a true live-work-play neighborhood.

It could also be a catalyst for additional development. Publix is known as a bellwether of retail viability, and where it locates, other retailers and grocers tend to follow.