Mercy South to Break Ground on $75 Million Emergency Department Expansion and Redesign

In order to meet the growing needs of its community, Mercy Hospital South is expanding and redesigning its entire emergency department. A ceremonial groundbreaking kicks off the project on Thursday, Sept. 26, including a blessing by Archbishop Mitchell Rozanski.

The $75 million dollar redesign will expand the existing emergency department from 39,000 square feet to 65,000 square feet. The additional space will enable caregivers to better serve patients by providing:

Mercy South is already one of the busiest emergency departments in the St. Louis region with more than 67,000 visits in fiscal year 2024. It currently treats about 1,000 more patients per month compared to the previous year at the same time with EMS crews delivering more patients by ambulance and helicopter.

“Not only are we seeing more patients coming to us for care, more patients are acutely ill,” said Sean Hogan, Mercy South president. “We’re seeing significant increases in the number of stroke, heart attack and trauma patients seeking care at Mercy South. This redesign will help us continue the high-quality care we provide, improve patient experience and meet the growing needs of our community.”

Mercy South is a comprehensive stroke center, the only Missouri designated Level 1 stroke center and Level 1 STEMI (heart attack) center and trauma center serving south St. Louis County. It is the closest stroke center for every patient south of St. Louis County all the way to the Arkansas border.

“We are committed to using our resources to invest in the communities we serve,” Hogan said. “We need increased access to emergency care. It’s an important step to improving the overall health of our community and a major commitment by Mercy to provide care where it is needed.”

The project is scheduled to take about two and a half years, with completion expected in spring 2027. The emergency department will remain open and serve patients throughout construction. Ambulances will be directed to a temporary ambulance entrance for portions of the project. Patients arriving by car will be directed to a new, temporary emergency entrance with a temporary waiting area.

To create the additional space for the expansion, the footprint of the emergency department will be extended north toward Kennerly Road into what is currently the emergency department parking lot, requiring the closure of that lot and reassignment of some parking spaces. To provide space for construction crews, the main drive will be temporarily narrowed from the existing four lanes to one lane in one direction, restricted to ambulance traffic only. Detours around this restricted area will be in place to allow patients, visitors and co-workers to reach every part of campus. However, drivers are strongly encouraged to enter campus on the same side as their destination.