The National Aquarium in Baltimore plans to build a $5.4 million waterfront park in Westport, where it hopes eventually to shift its Animal Rescue Program from Fells Point under a larger redevelopment plan.

Officials at the Aquarium unveiled their plans Monday for the 12.5-acre site along the Middle Branch of the Patapsco River, a project which has been in the works for about a decade.

The property is across the Middle Branch from developer Patrick Turner’s $1.2 billion Westport project in South Baltimore before the Hanover Street bridge if traveling from downtown. The nonprofit hopes to open the park, to include walking and biking trails, early next year.

Those plans are part of a larger, $50 million redevelopment slated to include classroom space, room for public demonstrations and a newer facility for its animal rescue efforts. The economic downturn forced the Aquarium to suspend fundraising for that portion of the project last year.

The nonprofit has spent the past year cleaning up contamination 101 W. Dickman St. and readying it for its proposed Center for Aquatic Life and Conservation Inc.

As part of that cleanup, Baltimore contractor Potts & Calahan Inc. removed about 7,500 tons of contaminated soil, put there as debris from construction and demolition projects in the region.