The city of St Louis is planning a US$45m (€40.2m, £34.4m) addition to its historic Union Station – a 75,000sq ft (7,000sq m) aquarium.

Once the largest and busiest passenger rail terminal in the world, the 122-year-old St. Louis Union Station now serves as a tourism destination and event space, featuring such attractions as the THEA Award-winning Grand Hall experience.

Housing thousands of aquatic species, the aquarium will sit in the former mall area of Union Station. The aquarium’s main feature will be a shark tank holding one of the largest collections of sharks in the Midwest, with a rope bridge similar to that of Newport Aquarium’s world-first Shark Bridge crossing the 385,000-gallon shark tank. An 8,500sq ft (790sq m) events space using the shark tank as a backdrop will also be included.

The aquarium will be part of a larger US$70m (€62.6m, £53.5m) family entertainment complex located at Union Station, which was purchased in 2012 by Maryland Heights-based Lodging Hospitality Management (LHM). In addition to the aquarium, the entertainment complex will feature restaurants, retail, rides, and a 200-foot (61m) Ferris Wheel with heated and air conditioned gondolas.

The first phase of development — the Fire & Light Show at the Lake — will open by November 2016. Created by Groundswell Design of Philadelphia, the show emanates from nine fire pods submerged in a pool. Tube lights, hung from trees and a light show projected onto the ceiling panels of the train shed above the lake, will create a display synchronised to music on view every 30-minutes on the hour.

“We are excited to bring this highly anticipated attraction to St. Louis,” said Bob O’Loughlin, chair and CEO of LHM and owner of St. Louis Union Station. “The St. Louis Aquarium will anchor the development that will transform St. Louis Union Station and reposition it as a family attraction destination.”

Construction is planned to begin in Q3 2016 with an anticipated completion date of Q3 2018. Contractors and architects have not been selected for the aquarium, with a representative of Union Station telling Attractions Management an announcement is expected in Q3.