Workshops focus on comprehensive solutions to challenging interior flooding in Nation's capital

By Sarah LazoDecember 13, 2018

Army Corps, others host interior flooding workshop in nation's capital
Stacey Underwood, U.S. Army Corps of Engineers, Baltimore District, Silver Jackets Program coordinator, speaks to attendees at the 2018 DC Flood Summit held at the University of the District of Columbia, Sept. 5, 2018. Attendees learned about and dis... (Photo Credit: U.S. Army) VIEW ORIGINAL

The Federal Triangle and its surrounding area is the center of tourism in the District of Columbia. The area includes the National Mall and is home to some of our nation's most iconic and significant buildings, including the Smithsonian Institution, Internal Revenue Service Headquarters, U.S. Commerce and Justice departments, and National Archives. This means there is a lot at risk when it comes to flooding.

The District of Columbia is situated in an area that makes it prone to flooding. It can be flooded via three ways: Potomac River freshwater flooding from the upper watershed, Potomac River tidal/storm surge flooding and interior flooding.

The District of Columbia Levee System, which was constructed by the U.S. Army Corps of Engineers (USACE) and is maintained by the National Park Service (NPS), reduces risks from major flooding along the Potomac River; however, the threat of interior flooding remains.

Interior flooding is caused by heavy localized rainfall that descends directly over the District in a short period of time and overwhelms stormwater systems.

The Federal Triangle area experienced a major interior flood in summer 2006 that resulted in disruption of and millions of dollars in damages to buildings, utilities and the Metro system. Double digit rainfall totals affected parts of the region over the course of five days. At Reagan National Airport, nearly 8 inches of rain fell in a 24-hour period, surpassing the previous rainfall record by more than one inch.

Since this time, a few studies have been conducted and various agencies have worked to flood proof their individual buildings; however, a comprehensive solution does not yet exist. This lingering hazard led the District of Columbia Silver Jackets interagency flood risk management team to host two workshops in summer 2018 specifically focused on interior flood risk in the Federal Triangle, bringing together more than 75 facility managers, planners, architects, engineers, environmental specialists and emergency managers from federal and district agencies, international embassies, non-profit organizations and academia.

Agencies represented included USACE, NPS, District Department of Energy and Environment (DOEE), National Capital Planning Commission, Architect of the Capitol, General Services Administration, National Archives and Records Administration, National Gallery of Art, U.S. Commissions of Fine Arts, and the Smithsonian Institution.

"We cannot wait for another event like the 2006 flooding before we take further actions," said DOEE DC Floodplain Manager and DC Silver Jackets Co-leader Phetmano Phannavong. "These workshops provided a forum for stakeholders to openly discuss potential solutions to the flooding risks we face together. As flood risk management leaders in the District of Columbia, the DC Silver Jackets team is always seeking solutions to reduce flood risks in collaborative and creative ways."

The intent of the first workshop held at the University of DC June 6 was to provide attendees with an overview of the flood history and risk in the Federal Triangle; discuss steps individual agencies are currently taking to flood proof their properties via a panel discussion; present types of interior flood risk management measures; and engage through an interactive breakout session on key opportunities and challenges related to interior flooding in the area.

"We were provided with everything a new or even a seasoned facilities manager needs to learn about the history of flooding in the Federal Triangle area, and, more importantly, dialogue with leading experts on how to best mitigate flood risk to our own facilities in the future," said National Gallery of Art, Facilities Management Chief Dave Samec. "During the panel discussions, we learned about the flood proofing techniques that other facilities are currently employing, as well as other larger-scale holistic options, and this was followed up with frank conversations during the breakout session regarding the pros and cons, costs and other considerations for each."

The second workshop, also held at the University of DC, Sept. 5 focused on potential relevant interior flood risk management solutions for this area based on input gathered from the first workshop. Types of projects discussed included underground storage and/or conveyance out of the Federal Triangle, underground storage with parking, upstream detention techniques, restoration of natural drainage, and flood proofing of buildings. Breakout sessions focused on the identification of potential advantages and challenges associated with each type of project; potential funding opportunities and partnerships; and short-term interim interior flood risk management actions.

"With participants from various agencies with different backgrounds and responsibilities, including an international perspective with representation from the Danish, Dutch and Seoul governments, the afternoon breakout sessions were lively," said USACE, Baltimore District, Silver Jackets Coordinator Stacey Underwood. "The flooding problem and potential solutions are challenging, especially with the number of invested stakeholders in the area, and everyone was able to come to the table and share their views and learn from one another."

"The workshops make clear that cultural institutions, federal and district agencies and utilities must collaborate in the near term to develop shared solutions and seek funding to protect our assets and make them more resilient," said Smithsonian Institution, Associate Director for Planning Ann Trowbridge.

The project team is planning to meet with executive leaders of the area's primary agencies to discuss the flooding issue and next steps.

"Because of the information gathered from these workshops, we are now armed with a wealth of perspectives and ideas to provide stakeholder leadership with the goal of achieving consensus on a path forward for reducing interior flood risk in this critical area," said Underwood.