Climate Resilient Land Use Glossary

Climate Resilient Land Use Strategies_pano
Climate Resilient Land Use Glossary


Base Flood Elevation

The minimum elevation of the lowest floor of a building, which is determined by the water elevation above base sea level during a 1% annual chance flood event (designated on FEMA flood maps). 

Design Flood Elevation (DFE)

Defined by FEMA as the height of the lowest occupied floor, this consists of the Base Flood Elevation plus the required freeboard.  


Additional elevation required above the Base Flood Elevation to provide a safety buffer between the flood level and lowest occupied floor (i.e., the distance between Base Flood Elevation and Design Flood Elevation).  

Federal Emergency Management Agency (FEMA)

The Federal agency in charge of responding to natural and man-made disasters. The agency also manages the National Flood Insurance Program (NFIP) and issues flood maps. 

Flood Insurance Rate Maps

Maps produced by FEMA showing flood risk and depths based on existing and historic flood data. FIRMs do not include expected flooding due to projections of Sea Level Rise or other climate change impacts.

FEMA Flood Map Service Center: 

Green Infrastructure (GI)

Integration of natural systems and elements to provide a specific service, often water infiltration, filtration, or storage. May include engineered elements in addition to natural elements. May also provide co-benefits such as shade, cooling, wild-life habitat, recreation etc... 

Low-Impact Development (LID)

Term used to describe site design and stormwater management practices used to manage runoff and pollutant loadings on-site or as close to on-site as possible. 

Moderate Flood Hazard Area

The designated floodplain in the flood insurance rate maps representing the 0.2% (1 in 500) chance annual flood risk.  

National Flood Insurance Program (NFIP)

Managed by FEMA, this national insurance program provides flood insurance coverage for buildings and contents, such as personal belongings. Property owners with federally-backed mortgages are required to purchase flood insurance if their property falls within the SFHA FEMA floodplain.  

Nature-Based Solution

A term used to describe projects that use ecosystems to provide services and benefits through the preservation, conservation, restoration, or creation of natural systems such as wetlands. May provide additional co-benefits such as outdoor space and recreation, wild-life habitat, and carbon reduction or sequestration.  

Sea Level Rise (SLR)

Sea level rise is the amount that the ocean elevation will increase due to climate change. The amount of SLR projected is based on different greenhouse gas emissions scenarios, due in part to the degree that polar ice caps melt. Sea Level Rise rates are also impacted by local topography and land subsidence.  

Substantial Improvement

According to the building code, a building improvement including reconstruction, rehabilitation, and additions for which costs are equal to 50% or more of the market value of the property before construction.   

Special Flood Hazard Area (SFHA)

The designated floodplain in the flood insurance rate maps representing a 1% chance annual flood risk. The SFHA is considered a high-risk flood area delineated on the map as zones A or V.  

100-Year Flood

A colloquial term for the SFHA to represent the 1% (1 in 100) chance of flooding annually. The 1% chance annual flood is what is used for the FEMA special flood hazard area.