It took a modern Trench cutting methods and Remixing Deep (TRD) machine to help excavate three 18th-century sailing ships at the Robinson Landing site on the Alexandria, Va. waterfront.
Working under a strict 26-month schedule and within the contractor’s guaranteed maximum price of $145 million, the design-build team on the Duke Ellington School of the Arts completed the project before the 2017-18 school year.
Faced with economic and environmental uncertainties, the Hampton Roads Sanitation District (HRSD) was challenged to adapt its 249 million gallons per day wastewater-treatment network to address and maintain reliable service to more than 1.7 million residents across southeast Virginia while safeguarding the region’s diminishing water supply and ecologically sensitive Chesapeake Bay.
Designed to substantially reduce combined sewer overflows to the waterways of the nation’s capital, the $240-million, 12,300-ft-long hydraulic tunnel traverses a route that includes varying subsurface conditions, fragile utility networks and above-ground environments ranging from rivers and parks to densely populated urban neighborhoods.