Stiver Engineering responded to an emergency situation regarding a sinkhole beneath the control building at the Houston Water Control and Improvement District’s No. 47 wastewater treatment plant. The sinkhole, which was roughly 20 feet wide and 30 feet deep, was jeopardizing the building’s stability as well as the plant’s effluent line. Stiver proposed a solution to save the control building and keep the plant operational during construction. We developed and delivered a design and provided support to the material supplier and the contractor until project completion.