Geotechnology’s Services Go Deep at The Muny

Helping an Iconic Theater to Build Upon a Solid Foundation

St. Louis Municipal Opera Theatre (commonly known as The Muny), is America’s oldest and largest outdoor musical theater. The nation’s biggest stars and stars-to-be have traversed the stage of this 11,000-seat renowned venue. Currently, a rebuild of the theater is being undertaken to address its critical structural needs, utilize state-of-the-art stage technology, and be able to deliver top-notch entertainment for many future generations.

Geotechnology, Inc., a leading provider of geotechnical and environmental engineering, geophysics, materials testing and drilling services, is a vital contributor to this Muny project.

When the project is completed, audiences will experience many visual and sound improvements, including Broadway-style LED lighting and digital screens, and an expanded climate-controlled orchestra pit. Although not as easily discernible, Geotechnology’s contributions are at the foundation of the project.

The Muny project includes removing and replacing the existing stage and construction of a basement under the stage. The new stage and surrounding structures (new east and west towers and a light bridge) will have multiple stage decks and stage floor tracking. The east tower will include a new house management office, the west tower will contain orchestra rooms, a sound room and prop room.

Working for Tarlton Corporation pre-construction, Geotechnology performed subsurface exploration to provide the geotechnical aspects for the design and construction of removing the existing stage and adding a basement, 12 to 15 feet below the existing main stage.

“Geotechnology provided subsurface exploration services previously for The Muny in 2006 and again in 2013, so we had earlier reports for comparisons,” said Geotechnology Senior Project Manager Dan Greenwood. “Combined with our new test results, our past findings helped us develop a more thorough geotechnical report.”

For this project, Geotechnology drilled four borings, and used an automatic hammer to perform Standard Penetration Tests (SPTs) and obtain split-spoon samples and relatively undisturbed Shelby tube samples. A geologist from Geotechnology was on-site to provide direction during field exploration, observe drilling and sampling, assist in obtaining samples, and prepare logs of the materials encountered.

Geotechnology tested the samples in its St. Louis AASHTO- AMRL/CCRL Certified and USACE Validated laboratory.

The north stage area was built atop a piped portion of a River Des Peres tributary which traverses the park. Urban fill associated with the filled creek alignment was encountered in the test borings. Removal and replacement of the urban fill was required in some portions of the basement, and deep foundations were extended to bedrock.

Construction began immediately after the close of The Muny’s 2018 season in August and will be completed prior to the opening in June of the 2019 season. Geotechnology will be providing the Muny with construction observation, materials testing and special inspections services throughout this period. “There are always variables to consider on a project this diverse,” said Greenwood. “The Muny has a 100-year history of entertaining hundreds of thousands of people. We are pleased to have the capabilities to contribute to such a meaningful and challenging project.”

Established more than 30 years ago, Geotechnology, Inc. is a professional corporation offering a comprehensive range of consulting services in applied earth and environmental sciences, including geophysics, water resource management, geotechnical and environmental engineering, materials testing and drilling. Geotechnology has provided expertise on thousands of major construction projects in the Midwest and Mid-South regions. Geotechnology is ranked #406 in ENR’s Top 500 Design Firms in 2018. Geotechnology, Inc. is based in St. Louis, Mo., and has 10 offices in Missouri, Illinois, Kansas, Ohio, Kentucky, Tennessee, Mississippi and Arkansas. For more information, visit

Photo Above: Geotechnology mobilizing a light drilling rig to explore the geologic conditions beneath the Muny Stage