Thinking Beyond Flood Maps

Welcome to “Thinking Beyond Flood Maps—Using FEMA’s Coastal Data to Reduce Risk and Build Resilience.” 

Coastal communities are using flood risk data in powerful ways to build resilience. FEMA developed this story map to highlight their work. The story map describes ways you can use datasets and products developed during FEMA coastal flood risk studies. Doing so can reduce your community’s risk and help you make resilient decisions.

FEMA updates a community’s flood maps to reflect changes that occur over time. The flood risk studies that update the maps result in large amounts of data. Communities can use this data in many ways, including those described below. 

For information about the risks and hazards that are analyzed to update flood maps in coastal communities, visit  An Introduction to FEMA Coastal Floodplain Mapping .

Our coasts are home to vibrant communities, vital resources, recreational destinations, and robust economies. About 40 percent of the United States’ population lives in a coastal county. The National Oceanic and Atmospheric Administration (NOAA) estimates that at least 10 million Americans moved to a coastal area in the last decade.  

But what makes these areas so distinctive also puts them at risk. Flooding is the nation’s costliest natural disaster. In the United States,  7 of the 10 most expensive disasters  were caused by coastal storms. As the coastal population grows, more people and properties are at risk from coastal storms and flooding.

Coastal environments are dynamic. They are constantly reshaped by the forces of nature. Land use changes and rising average temperatures and sea levels may increase flood risk. Many communities see flooding from high tides more often now. This can lead to road closures, overwhelmed stormwater systems, and disrupted business districts.  By 2050, high tide flooding is likely to occur between 25 and 75 days per year, depending on location.  It is vitally important for coastal communities to make informed decisions about planning, land use, and building codes. Doing so today will reduce their risk and increase their resiliency in the future.

Your community can reduce coastal flood risk and build resilience to natural hazards in many ways. A local community can adopt floodplain management standards or codes that exceed FEMA's minimum requirements. Add flood mitigation projects to existing planning processes. Robust, integrated planning is another key tool. Use Capital Improvement Plans and funding to protect, replace, or redesign your infrastructure. Resilience-building and mitigation projects offer many benefits, such as improved public spaces and stronger, more disaster resilient buildings - and can generate a high return on investment.

Along much of the Pacific Coast, tsunamis are an often misunderstood coastal flood risk. While FEMA does not directly analyze tsunami risk through its flood insurance studies and FIRMs, FEMA participates in the  National Tsunami Hazard Mitigation Program  (NTHMP) administered by NOAA and supports efforts led by State, local, Tribal, and Territorial governments to reduce risk within coastal communities. NFIP insurance policies also cover damage from tsunami flooding. 

The coastal city of Aberdeen, Washington wanted to be more prepared for a tsunami. With the Washington Emergency Management Division (EMD) and Washington Department of Natural Resources (DNR), FEMA developed the  City of Aberdeen Risk Visualization Viewer . On this interactive map, users can pan and zoom through the city to examine potential flooding from a tsunami. The tool shows tsunami flooding areas and the 1-percent-annual-chance coastal floodplain. Users can also find evacuation routes and assembly areas that were designated by the city. 

Using the best available federal, state, and local data, the tool gives people in Aberdeen a fuller picture of their flood risk. It incorporates local landmarks so users can see how flooding may affect the places they know best. Evacuation routes show them the fastest way to higher ground. This information can help Aberdeen prepare for an emergency, as well as planning for post-tsunami recovery.

The viewer is based on a tsunami caused by a 9.0 magnitude earthquake along the Cascadia subduction zone and uses results generated by the state’s tsunami model. This includes tsunami flood locations and depths throughout the community. The model results were pulled into ArcGIS Online to help community members address two questions:

1. Do I live, work, or play in an area vulnerable to flooding due to a tsunami? 
2. If there is a tsunami, how bad might the flooding be at my location?

• 3D Buildings and Local Landmarks – Three-dimensional (3D) building footprints help viewers recognize where they are. Where available, local landmarks like schools, churches, and restaurants were included. When exploring the map, users can see how high the flood water reaches on each building. This is a powerful image of flooding in specific areas.
• 3D Terrain Imagery – A detailed 3D base map, including tree cover, helps users find the nearest high ground from different vantage points at street level.
• Evacuation Routes and Assembly Areas – Evacuation routes help people prepare and think about how to reach the nearest high ground and designated assembly areas. This builds on the city’s successful Yellow Brick Road program, which uses signs to guide residents to higher ground.

This viewer provides an additional tool for coastal communities like Aberdeen to become better prepared, respond more effectively, and develop mitigation strategies that will ultimately reduce risk.

Communities in coastal Maryland are particularly vulnerable to rising sea levels. More than two dozen of these communities could see chronic sunny day flooding and sinking land by 2025. Baltimore County and the City of Baltimore—highly populated areas—frequently face flooding from both rain events and coastal flooding. Between 1996 and 2017, the city had more than 85 flood events. These were associated with storm surge, high tide coastal flooding, flash floods, and heavy rain. As a result, the county and city have gradually adopted higher building standards in vulnerable areas.

In 2014, the Maryland Department of Natural Resources established a  Coast Smart Council . The council was charged with developing new criteria for siting and designing state-funded buildings. They are doing this in ways that reduce the impacts of sea level rise and coastal flooding. In 2015, the state’s  Coast Smart Construction Program  went into effect.

These new requirements apply to projects funded, planned, and built by the state. For projects in the Special Flood Hazard Area (SFHA), the lowest floor must be two feet above the Base Flood Elevation (BFE) in that location. Critical facilities must be built outside the SFHA. They must also be protected from damage or events that could block access to the facility during a more severe flood. This is particularly important for buildings like hospitals and shelters. Making sure these are open and easy to get to during an emergency is a major part of community resilience.

In 2016 and 2017, Maryland continued to build on these requirements. Its Critical Area Program developed a  Coastal Resilience Planning Guide  as a resource for planners. The Department of Natural Resources established the  Resiliency through Restoration Initiative  that encourages the use of nature-based projects in local communities. The projects can restore, enhance, and create coastal habitat while protecting communities from storm damage. 

In 2018,  state legislation  expanded the Coast Smart Siting and Design criteria to include local capital projects that are at least 50-percent funded by the state and cost more than $500,000. To reflect these changes, the Coast Smart Council will adopt new siting and design standards in 2020. The standards will require eligible structures to be built (or rebuilt) with their lowest floor three feet above the BFE. The benefits include:

• Connecting siting and design with the flood zones shown on FEMA’s flood maps;
• Using existing, available data from FEMA and Maryland mapping products; and
• Being consistent with FEMA best practices for siting critical facilities.

Additionally, the updated siting and design standards will apply to eligible structures in areas outside the coastal SFHA. Maryland will expand the area subject to the new standards further inland by adding three feet of freeboard to the FEMA stillwater elevation. The expanded flood risk area will help local jurisdictions and state agencies plan for future flood impacts more proactively by encouraging resilient building further inland.

FEMA is currently working with New York and New Jersey to restudy the area’s coastal flood risk. The restudy, which was launched following New York City’s appeal of the preliminary flood maps released after Hurricane Sandy, will re-examine flood hazards for certain counties in coastal New York and New Jersey, using new storm surge analysis and overland wave modeling. The restudy will produce robust flood maps that show the area’s current risk of coastal flooding. It will include extensive model validation, data from recent storm events, and an evaluation of the effects of tides.

Regional partnership, engagement, and transparency have been essential to the success of the restudy. The Coastal Advisory Panel includes representatives of New York City, New York State, New Jersey, the Port Authorities of New York and New Jersey, FEMA, and independent coastal modeling experts. This group was formed to allow stakeholders to ask questions, provide comments, and be engaged throughout the restudy process.

New York City, which engaged early and often in the restudy process, also regularly provides feedback on the modeling decisions and process. Building on FEMA’s efforts to provide current coastal flood risk maps, the New York City Mayor’s Office of Resiliency will also use the storm surge modeling from the restudy as the foundation for developing Future Flood Risk Maps. 

These new maps will show property-specific future flood risks that include the effects of sea level rise, based on the latest projections from the  New York City Panel on Climate Change (NPCC) . The NPCC projects that sea level rise will increase the extent and depth of the 1-percent and 0.2-percent-annual-chance floods, exposing more residents and structures to flooding. To adequately prepare for these increased risks, New York City’s property owners, planners, and designers need more information about future flood risks.

The Future Flood Risk Maps will support resilient design and planning efforts throughout the city by:

• Providing site-specific information on future conditions;
• Integrating sea level rise data into code requirements for the current and future floodplains; and
• Centralizing data about current and future flood risks.

New York City expects to complete the Future Flood Risk Maps in spring 2021. Peter Adams, Senior Policy Advisor with the Mayor’s Office of Resiliency, is overseeing the project.

“Whenever designers and planners are thinking about flood risk, they are thinking not just about flood risk today, but about what flooding will look like for decades to come. Buildings designed today must withstand the existing impact of climate change and increasingly powerful floods that are impacted by sea level rise. By incorporating FEMA’s modeling and the best sea level rise projections available in our Future Flood Risk Maps, New York City will provide designers with the information they need to design for a more resilient future.”- Peter Adams, Senior Policy Advisor

Pinellas County, FL, is vulnerable to flooding from both heavy rainfall and tropical weather events. Through an innovative, targeted, and multi-faceted flood risk outreach and education program, the county increased risk awareness for a variety of local stakeholder groups.

The targeted effort began in 2014, with the launch of the Pinellas County Program for Public Information (PPI). Through the PPI, the county streamlined its flood risk outreach and was able to document various activities for Community Rating System credit, which led to the reduction of flood insurance premium costs for policyholders.

To support the PPI efforts, the county developed the Pinellas County Flood Map Information Center, an interactive, online mapping platform. When the Map Information Center was first launched in 2014, it gave stakeholders the ability to find the current flood zone for a specific location, based on the county’s effective flood maps. As the Map Information Center gained traction, the county recognized the value of incorporating additional information to meet the diverse needs of the community. For example, the PPI worked with the county’s Office of Emergency Management to incorporate information about the difference between flood zones and evacuation zones.

As the county’s flood awareness outreach program grew, so did the demand for an easy-to-navigate, mobile-friendly platform. In 2020, the county replaced the Map Information Center with a new and improved  Pinellas County Flood Map Service  to meet this need. On this mobile-friendly platform, users can easily navigate to various maps. The site gives them the ability to:

• Compare effective and preliminary Flood Insurance Rate Maps, which will indicate where flood risk has changed over time;
• Determine the potential storm surge depth at specific locations;
• Download a property’s elevation certificate, which can be used to rate flood insurance policies, inform floodplain management, etc.;
• Provide current water levels for both coastal and riverine locations; and much more.

In collaboration with the  Pinellas Realtors Organization (PRO) , the county also launched the  Real Estate Flood Disclosure Training Program  in 2016. The program offers at least two training sessions per year to prepare local real estate professionals to answer questions potential buyers may have about flood risk. The topics covered include flood map basics, flood insurance concerns, floodplain development, and how to use the Flood Map Service. This training is in high demand and classes regularly reach their registration limits. Adapting to the challenges of the recent public health crisis, the county successfully held its first virtual training in April 2020.

These training sessions have made the Flood Map Service a go-to resource for real estate professionals in Pinellas County. After participating in the training, real estate agents are better equipped to help give home buyers the information and background they need to understand their flood risk and make informed decisions. The mobile-friendly Flood Map Service is particularly useful to agents in the field, who may not have access to a computer when showing clients properties. Using the Real Estate Disclosure application located on the Map Service, real estate agents can download a completed brochure called  Know Your Flood Risk Before Buying or Building in Pinellas County . This gives their clients critical flood risk information for a specific property.

Pinellas County’s robust flood awareness outreach and education sparked the interest of several other Florida counties, as well as other areas in the United States, including New York City. The county offered support and resources to these locations to help them launch similar programs.

FEMA has many partners in building a more resilient nation. These include NOAA, the U.S. Geological Survey, the U.S. Army Corps of Engineers, the Environmental Protection Agency, and many state, local, and private organizations. Some tools and resources from those partners are linked below.

Communities with an approved hazard mitigation plan are positioned to build their resilience. The mitigation plan encourages whole community involvement, assessing risk, and using a wide range of resources to develop mitigation strategies that protect people, economies and the environment.

Having an approved mitigation plan is a prerequisite for certain kinds of non-emergency disaster grants, like the Flood Mitigation Assistance and Building Resilient Infrastructure and Communities programs.

• Curious if your community has a plan?  Check your status online !
• Looking for help creating or updating your plan? FEMA provides resources on the  Mitigation Planning  pages.

Additional resources include: