The clock has started ticking for a potentially ambitious development at the Seven Corners Gateway site in downtown St. Paul after the city's Housing and Redevelopment Authority Wednesday granted tentative developer status to Opus Development Co. and Greco Real Estate.

The approval starts an 18-month process that includes environmental investigation, finding housing partners and hotel owners and completing project design plans. If Opus meets all required benchmarks in the agreement, the city would enter into a full development agreement.

Until now, the Gateway proposal has been short on specifics. The prospective developers, however, have said that the project will include a public plaza, retail, apartments and a hotel on the 2.4-acre site that is bounded by W. 7th Street and Kellogg Boulevard.

City officials say they'll have a much better idea of what the project will look like once the parties finalize a development agreement.

"We can get to work right away," Ellen Muller, economic development manager for the city of St. Paul, said after the vote. The goal is for construction to begin shortly after the process is completed.

Council Member Dan Bostrom, who also sits on the HRA board for the city's nearby RiverCentre, said the next 18 months will give the city and developers time to "think big" on what may go into the site. The development and its new hotel is projected to become a magnet for conventions and national meetings by connecting by skyway or tunnel to the city's nearby Seven Corners parking ramp, as well as RiverCentre, the Xcel Energy Center and the Holiday Inn across the street.

"This really has the potential to become a much bigger project," Bostrom said. "Don't think too small. Let's see if something like this makes sense."

For years the site has been eyeballed for possible retail, entertainment, or medical campus development. But none of those ideas materialized.

A new Lowertown ballpark, the renovated Union Depot, the soon-to-be-expanded Catholic Charities complex, as well as Opus' development of the former Seven Corners Hardware site, provide new momentum for downtown, Muller said, and make the timing right for development of what is called the Gateway.

Dave Thune, the council member who represents the Seven Corners area, said the planning that begins now should not be short on ambition.

"This needs to be a major entrance to the city," he said. "So the architecture and design and features all need to reflect a major city."

In other developments Wednesday:

The City Council approved Mayor Chris Coleman's proposal to pump $42.5 million into road improvement, bike paths and a renovated Palace Theatre. "This is a huge step forward in the revitalization of St. Paul," Coleman said in a statement. Financing for the work comes from recently retired bonds for RiverCentre, which frees up funding for several other projects, including:

• $8 million to reconstruct Jackson Street and complete the first phase of a downtown bike loop.

• $13.2 million toward completing the Grand Round — including road reconstruction and bike pathways along Wheelock Parkway, Johnson Parkway and Pelham Boulevard.

• $9.5 million for other streets and public spaces.

• $2 million to add green space along the Green Line, including Dickerman Park.

• $8 million to turn the Palace Theatre into a live music venue.

• $1.8 million for fiber optic infrastructure.

James Walsh • 651-925-5041