Wanted: A developer willing to help close a key gap along the Mississippi Riverfront.

That firm must be willing to work with the Minneapolis Park and Recreation Board and several community groups to re-imagine a vacant 3.55-acre site along the river north of downtown.

"We want to see something that's a great complement to the park on the river," Michael Schroeder, assistant superintendent of planning services at the Park Board.

That land, called Parcel D, is just north of the Plymouth Avenue Bridge on the east bank of the river. For decades it was home to Scherer Brothers Lumber, but is now part of an 11.7-acre redevelopment project that will include parkland, a recreational trail and a reclaimed island. Parcel D is the only portion of the project that will be developed privately. The rest will be spearheaded by the Park Board with cooperation from the chosen developer.

Though the park has yet to be developed and the 4-acre Hall's Island has yet to be re-established, the Park Board has already opened a mile-long section of the Mississippi East Bank Trail, which connects to an extensive trail system down river. In the mid-1960s, Scherer Brothers acquired what was once Hall's Island and filled in the eastern channel to expand its storage yard. The Park Board bought the once-polluted site in 2010 for $7.7 million.

Last year, Graco Inc. considered partnering with Ryan Cos. to develop its new corporate headquarters on the site, but the plan was scrapped.

Schroeder said that Ryan's withdrawal from the process doesn't mean they might not try again. The Park Board is not yet expecting developers to present a detailed proposal for the site. Instead, the firm selected will have to work with a 15-member community advisory committee and the Park Board to craft a concept plan.

"We have design direction, we now need the insights of a developer ... that will lead to a project that someone will actually want to build," said Schroeder.

He said that because the Park Board doesn't have the funds to operate a new park, it expects the developer to participate in a ground lease that would help operate and maintain the park.

Though only pollution remediation and a trail have been built, the project has already been years in the making. In 2010, the Park and Recreation Board, the Minneapolis Parks Foundation, University of Minnesota College of Design and Walker Art Center launched an international design competition aimed at creating a plan to redevelop a 5.5-mile stretch of the river north of the Stone Arch Bridge.

The Minneapolis Riverfront Development Initiative was established along with a 20-year vision for the Mississippi-riverfront parks called "RiverFIRST." A conceptual schematic design was created for the entire site and the Park Board created the Above the Falls Regional Park Master Plan to help guide future development.

The winners of the 2011 design competition proposed redredging the channel and building a bridge. Their plans also call for the creation of a beach and a better connection to the riverfront for recreational uses.

Edna Brazaitis, a community advisory committee member, said that she doesn't have a preconceived notion of how Parcel D is used, but she has encouraged the Park Board to be open to different uses even if current zoning may not allow them.

"That can mean a number of things including but not limited to commercial uses that draw in the public and benefit from the park's activities and its skyline views of the city," she said. "It could be residential, where there are eyes on the park providing activity all week long and a sense of safety. It could be a use that I couldn't even imagine."