JBAB Overflow and Diversion Structures Project

JBAB Overflow and Diversion Structures


The JBAB Overflow and Diversion Structures Project, located on Joint Base Anacostia-Bolling (JBAB) military facility, included the construction of a tunnel overflow structure and diversion chamber. The diversion chamber diverts excess combined sewer flow to the Blue Plains Tunnel where it is stored and eventually treated at the Blue Plains Advanced Wastewater Treatment Plant prior to discharge to the Potomac River. The overflow structure controls tunnel overflows to the Potomac River when its capacity is exceeded while providing solids and floatable control. The overflow structure has been architecturally designed to serve the dual purpose of providing a scenic overlook structure and providing views of the Potomac River and surrounding areas to JBAB personnel.

Scope of Work

  • Construction of a new diversion chamber to divert flow from the existing Potomac Outfall Sewers to the Blue Plains Tunnel
  • Construction of a new overflow structure to relieve the Blue Plains Tunnel to the Potomac River when its design capacity is exceeded
  • Installation of new hydraulic internals within the existing shaft constructed on the Blue Plains Tunnel
  • Demolition of an existing combined sewer overflow, abandonment of its outfall pipe, and restoration of the shoreline
  • Commissioning of Clean Rivers system south of RFK Stadium


DC Water worked closely with multiple stakeholders to provide timely information about the project, to solicit input, and to ease the burdens of construction. These stakeholders included affected residents, Joint Base Anacostia-Bolling, US Army Corps of Engineers, District Department of Transportation, National Park Service and the District Office of the Deputy Mayor for Planning and Economic Development. DC Water also coordinated with Advisory Neighborhood Commissions to provide regular updates.