The National Park Service selected The Cianbro Cos. of Maine for a project to rehabilitate failing seawalls along the Potomac River and Tidal Basin in the nation's capital. The $112.8-million design-build contract is part of nearly $500 million in infrastructure improvements the agency has planned around the National Mall ahead of the 250th anniversary of U.S. independence in 2026.
The walls by West Potomac Park in Washington, D.C. date to the late 1800s and early 1900s. A combination of age, rising water levels and poor drainage has caused portions of them to settle by as much as 5 ft, according to the Park Service. Water now flows over portions of the walls twice daily under normal tide conditions, threatening visitors’ safety, as well as the cherry trees. Some 1.5 million visitors visit the Tidal Basin annually.