Treasure Island Hotel

  • Location: Welch, MN
  • Architect: RSP Architects
  • Client: Mdewakanton Sioux Prairie Island Indian Community

Project Highlights

  • 184,00 SF hotel
  • Two side by side 7- and 8-story towers
  • Cast-in-place, post-tensioned concrete


The new Treasure Island Resort and Casino hotel adds 184,000 square feet and 306 rooms to the resort’s overnight guest capacity. Two side by side 7- and 8-story towers were constructed in two phases, using structural systems of cast-in-place concrete flat plate post-tensioned slabs supported on rectangular columns designed as a rigid frame. Creative structural design was required to route post-tensioned cables around elevators, wiring closets, and back-of-house areas, as well as to place multiple floor penetrations in the structure to accommodate mechanical/electrical systems. MBJ remained involved throughout construction, reviewing third party testing results, providing feedback, and helping the construction team find solutions to challenges that occurred in the field as the towers went up. The project also included considerable remodeling of the existing hotel and a link that connects to the new addition.