First-of-its-kind workshop focuses on storm surge, coastal flood risk in Maryland

Published March 20, 2015
National Hurricane Program Manager Chris Penney, Planning Division, U.S. Army Corps of Engineers, Baltimore District, speaks about storm surge forecasting to ‎more than 70 participants from various agencies to kick off the two-day Maryland Coastal Flood Workshop in Chester, Maryland, March 11, 2015. Penney works on hurricane evacuation studies with our partners.

National Hurricane Program Manager Chris Penney, Planning Division, U.S. Army Corps of Engineers, Baltimore District, speaks about storm surge forecasting to ‎more than 70 participants from various agencies to kick off the two-day Maryland Coastal Flood Workshop in Chester, Maryland, March 11, 2015. Penney works on hurricane evacuation studies with our partners.

"Wind gets all the notoriety," said Meteorologist Nate Hardin. "But, in reality, water is where our focus should be." 

Hardin works for the National Oceanic and Atmospheric Administration (NOAA), National Hurricane Center (NHC), Storm Surge Unit. He spoke to more than 70 participants from various agencies to kick off a two-day Maryland Coastal Flood Workshop, held March 11 - 12, in the small Eastern Shore town of Chester.

The interagency Maryland Silver Jackets team was able to get this first-of-its-kind workshop funded that brought together state, county, and city floodplain managers; emergency managers; planners; and regulatory specialists to talk about storm surge and coastal flood risk for this Mid-Atlantic state. The Maryland Silver Jackets is a unique team established in the spring of 2010 and is comprised of 16 agencies working together to reduce flood risk across the state. 

Held in the Volunteer Fire Department of Kent Island, which boasts the first English settlement in Maryland, the conversations that surfaced at the workshop could have great implications for the entire state that hugs the Chesapeake Bay. Storms are becoming stronger and more prevalent, and they are wiping out entire coastal communities - and not just along the Gulf Coast. 

"Flood risk is a shared responsibility, and this team works to leverage resources to identify flood risk management priorities, work on important coastal flooding outreach, and implement solutions to reduce flood risk in Maryland," said Stacey Underwood, Silver Jackets coordinator, U.S. Army Corps of Engineers (Corps), Baltimore District. 

In addition to coordinating multiple state Silver Jackets teams, the Baltimore District is home to the Hurricane Program Office, which centrally manages all Corps technical support as part of the Federal Emergency Management Agency's (FEMA) National Hurricane Program. Within this program, the Corps and FEMA work with NOAA to conduct hurricane evacuation studies with the ultimate goal of helping locals understand their evacuation timeline. 

There are more than half a million residents and approximately 300 miles of evacuation routes in Maryland vulnerable to storm surge flooding. 

According to NOAA, storm surge is defined as an abnormal rise of water generated by a storm - be it tropical storm or blizzard - over and above the predicted tide. 

Discussion topics at this coastal flood workshop included characteristics of storm surge and how to forecast it in Maryland, as well as current warning products and National Weather Service (NWS) tools being used at the local level. 

"This conference provides experts in the field with the opportunity to chip away at hurricane misconceptions," said Chris Penney, National Hurricane Program manager, Corps, Baltimore District. 

You may have heard the adage - run from water; hide from wind.

One common misconception is that the major concern during a hurricane is the intensity of the wind; however, coastal flooding is actually the main hazard of a hurricane most likely to cause death.

In the past 50 years, storm surge has caused 49 percent of the deaths in the U.S. attributable to Atlantic tropical storms. 

"You can breathe in 100 mph wind, but you can't breathe under 7 feet of water," said Penney. 

Another misconception discussed is that it is the category of the storm that influences storm surge. Category 1 Sandy tells a different story.

The size, intensity, central pressure, direction, and forward speed of the storm all have roles to play when it comes to storm surge effects, including the local features of the area. 

Interpreting surge forecasts and communicating that information to the public is not an easy task. Whereas the public has a tangible frame of reference when hearing a snow prediction of 3 inches, details of storm surge are a little hairier. The NHC is working on tools and improving forecasting models that will aid community leaders in eliminating complexities in how storm surge risk is communicated when a hurricane is bearing down on their area in order to provide simple information that people can act on. The end goal is to minimize severe under or over evacuation. 

The most accurate storm surge mapping tools provide data approximately 48 hours prior to the arrival of tropical storm winds. Current forecasting models incorporate tidal data and account for meteorological uncertainties in landfall location, size, forward speed, and intensity and also account for uncertainty based on historical errors. New tools simply communicate the risk of storm surge as the difference between water level and land height. 

This year, NWS is unveiling an interactive storm surge watch/warning experimental graphic that compliments the existing storm surge flooding map and highlights areas of life-threatening coastal flooding in order to better execute evacuations. This graphic, including colors, labels and text, was tested extensively by social scientists through focus groups to ensure the most intuitive tool would be put on the street. 

The workshop concluded with breakout sessions in which participants discussed the applicability of recent studies, and new tools and approaches to plan for hazard mitigation and resiliency in Maryland's communities. Maryland flood risk tools, as well as FEMA's non-regulatory Mapping, Assessment and Planning (Risk MAP) products were showcased, including a demonstration on using MDFloodmaps.com for importing storm surge data and overlaying the data on floodplain maps for comprehensive risk assessment. 

Storm surge inundation maps (SSIM) are not to be confused with flood insurance rate maps (FIRM), though both identify areas that are subject to flooding from coastal storm surge. SSIMs are not regulatory documents and are intended to support hurricane planning, preparedness and risk reduction. FIRMs are regulatory documents that support FEMA's National Flood Insurance Program; they establish flood elevations and are intended to be used for flood insurance ratings and building development. 

Maryland officials, through this workshop, are now armed to use the latest storm surge forecasting tools available in order to communicate risk in a way that resonates with their community members - to save lives and property. 

Other participating agencies at the workshop included Maryland Emergency Management Agency, FEMA, Maryland Department of Natural Resources, and Maryland Department of the Environment. 

The Corps supports flood risk reduction activities not only through its Silver Jackets Program, but also through its Levee Safety Program, Flood Risk Management Program, and authorities such as Floodplain Management Services, Planning Assistance to States, Advance Measures, and others. For more information on Baltimore District initiatives: http://bit.ly/NABlevees.