Infrastructure work at the old Chesterfield Mall site is picking up steam this month. The City of Chesterfield confirmed to First Alert 4 that crews are mapping sewer, gas, and water lines across the 96-acre property, the latest step in turning the former shopping center into a $2 billion mixed-use development called Downtown Chesterfield.

The mapping work falls within a broader utility and grading phase that developer The Staenberg Group says has been underway since late 2025. TSG announced in December that utility installation, relocation, and site grading had begun, focusing on a new road network and a 3.31-acre central park. The city has not detailed how this month's mapping work differs from the earlier activity, but the confirmation signals continued progress on the ground.

According to a December 2025 report in the St. Louis Business Journal, the infrastructure and grading phase is expected to run through summer 2027. After that, vertical construction — actual buildings — would begin. Over roughly 21 months, crews will regrade the entire site to a new elevation and install utilities for each development parcel.

"This is a meaningful milestone for the project," TSG founder Michael Staenberg said in a company announcement last December.

The finished vision is big: roughly 2,400 residences, 605,000 square feet of retail, more than a million square feet of office space, a hotel, and 1,000 free parking spaces, all connected by a 1.25-mile pedestrian loop. As of December 2025, TSG Vice President Tim Lowe said the company was in talks with five to seven multifamily and hotel developers. No update on those discussions has been made public.

Chesterfield Mall opened September 1, 1976, and closed exactly 48 years later on August 31, 2024. Demolition wrapped up earlier this year. The former Dillard's and Macy's anchor buildings still stand and are slated for future use in the new development.

No public hearings or city council votes tied to this construction phase have been announced. Residents can follow the project at downtownchesterfieldstl.com.