The City of Sioux City embarked on a significant expansion and renovation to the historic Sioux City Municipal Auditorium in 2000. The primary goal of this project was to create a multiple venue facility that can host a variety of activities and events such as minor league sports, concerts, and special touring events. Retractable/movable seating sections on the event floor create intimate settings for both small crowds and major, “sell-out” marketing events.

Mortenson built the new 190,000 square foot, 10,000-seat addition to the Sioux City Municipal Auditorium, known as the Tyson Events Center. Specific features include a horseshoe-shaped seating bowl that incorporates an end court upper deck to provide unique flexibility to resize the space with minimal moving parts. There are two blackout curtains and seven movable seating sections, so the building capacity can be shifted from a 6,400-seat hockey venue to a 10,000-seat concert venue quickly and easily.