While Hurricane Dorian left Northern Virginia untouched, the region might not be as lucky in the future, as climate change exacerbates the intensity of hurricanes and other extreme weather events.
A new coastal storm risk management study aims to help Northern Virginia leaders better understand and prepare for flooding challenges that their communities might face.
In an effort to share information and gather input from the public, study leaders from the U.S. Army Corps of Engineers and the Metropolitan Washington Council of Governments hosted an open house on Wednesday at the Martha Washington Library in Alexandria.
“After this summer’s historic flash floods affected communities throughout our region, flood risk is fresh on our minds,” COG environmental programs director Steve Walz said. “This study will help inform efforts by our area governments as we work to build a more resilient region.”
The Northern Virginia Coastal Storm Risk Management Study is currently in its early stages after launching in July.
Researchers have talked to elected officials and government staff from the various localities in the study’s scope, but feedback from residents and other community members about how they have been affected by flooding and where they see problems that need to be addressed could be valuable for understanding what happens on the ground during a flood.
While the open house has passed, members of the public can still share photos, information, and data that might be relevant to the study by email at MetroDCCoastalStudy@usace.army.mil.
“Anyone – residents who live in the area, or local jurisdictions or agencies that have information even just on how flooding has affected them in the area, or if they have data or ideas – we’re hoping that they will share that with us so that we can incorporate it into our process,” Corps of Engineers Baltimore District project manager Jacqui Seiple said.
Tasked with finding ways to reduce flood risks and improve community resiliency, the Northern Virginia Coastal Storm Risk Management Study developed out of a two-year study of the North Atlantic Coast that Congress commissioned in 2013 after Hurricane Sandy devastated the eastern seaboard in 2012, directly killing 72 people in the U.S. and producing an estimated $71 billion in damages.
The Army’s Corps of Engineers, a federal agency under the U.S. Department of Defense that is responsible for providing public and military engineering services, completed the North Atlantic Coast Comprehensive Study in January 2015, identifying the Washington, D.C., metropolitan region as one of nine high-risk areas that needed further analysis.
The Army Corps of Engineers’ Baltimore District signed an agreement on July 17, 2017 to split the study’s $3.5 million cost with the Metropolitan Washington Council of Governments, which serves as a coordinating organization for local, state, and federal elected officials in the region.
Though authorized to evaluate more than 57 square miles in the D.C. area, the team ultimately opted to focus on Northern Virginia, specifically Fairfax, Arlington, and northern Prince William Counties, the City of Alexandria, and the Metropolitan Washington Airport Authority’s Reagan Washington National Airport in Arlington.
ACE researchers decided to limit the study to Northern Virginia rather than the entire D.C. area after determining that the District and Maryland are further along than Virginia in their process for planning and evaluating flood risk management solutions, according to Seiple.
Walz agrees that Northern Virginia has not conducted as extensive research as its counterparts in the metropolitan area, but there are also more jurisdictions and agencies involved than in the District and Maryland, requiring more extensive coordination.
“Along the tidal Potomac, we've got three counties, the city of Alexandria, and the airport all right there affected by the coastal flooding,” Walz said. “…So, it’s not so much that we’re behind, which I think they’re behind a bit, but this really gives us a better ability to work together.”
Virginia has also taken some steps statewide to address the threat of flooding inland and along the coast.
Signed by Gov. Ralph Northam on Nov. 2, Executive Order 24 designated Secretary of Natural Resources Matthew Strickler as the Commonwealth’s chief resilience officer and directed him to develop the state’s first-ever coastal protection master plan to coordinate efforts along Virginia’s coast for addressing flooding and sea level rise.
The need for measures to protect both coastal and inland communities from floods has become increasingly apparent in recent years, as scientists say that warming waters and rising sea levels resulting from climate change contribute to the intensity of floods, hurricanes, and other storms.
Fairfax County got a taste of that extreme weather on July 8 when a storm dropped a month’s worth of rain on the D.C. area in a couple of hours.
The Fairfax County Board of Supervisors declared a local emergency on July 16 in response to the millions of dollars in property and infrastructure damages caused by the two to six inches of rain that the county received.
In addition to the over $2 million in damages and expenses calculated for the Fairfax County government, property owners reported an estimated $6.8 million in damages as of the end of July. The Virginia Department of Transportation recorded $6 million in road damage, including $4 million for Kirby Road alone.
Kirby Road and Swinks Mill Road in McLean, the part of the county hit hardest by the storm, remained closed into August due to the need for long-term repairs.
The extent to which a specific storm was created or exacerbated by climate change is hard to determine, but scientists generally agree that the human-driven phenomenon has led to stronger storms that bring more rain, and some studies suggest that Atlantic storms linger in one area for longer periods of time, according to Sept. 3 New York Times article on Hurricane Dorian, which swept through the Bahamas and the southeastern U.S. at the end of August.
“I think the storm history we've seen recently is consistent with what the scientists have been telling us they would expect to happen,” Walz said. “So, while no one individual storm can be pointed to as directly connected, the broader pattern seems to be happening.”
Seiple says that the Northern Virginia Coastal Storm Risk Management Study will incorporate projections for sea level changes into its analysis as part of an effort to understand how climate change will impact future flood conditions in the region.
While flooding is already a “persistent concern” throughout Northern Virginia, areas along the Potomac River and Fairfax County’s Cameron Run and Four Mile Run, which feed into the Potomac, are particularly problematic, according to COE Baltimore.
The region also has a lot of vulnerable but critical infrastructure located in flood zones, such as the Capital Beltway, the George Washington Memorial Parkway, Metro and other train railroads and stations, water supply, stormwater management, and wastewater treatment systems, and National and Dulles International Airports.
In identifying existing challenges and determining future conditions, the study team will provide recommendations to local jurisdictions and the Council of Governments that they could put in place to reduce coastal flooding and resulting damages.
Possible solutions range from barriers, levees, and tidal gates to updated flood warning systems, evacuation plans, and other policy or education strategies.
The study team expects to have recommendations available for public and agency input midway through 2020 and to put out a draft report that fall in the hopes of completing the project by the summer of 2022, according to Seiple.
The finished report will be delivered to Congress, which needs to approve the study’s findings and any funding required to implement recommended projects.
“We want to provide our Northern Virginia partners with the most suitable and effective recommendations to improve coastal storm resiliency and reduce life safety risks, economic damages, and other disruptions from flooding,” ACE Baltimore District commander Col. John Litz said.