Flood zones are geographic areas defined by the Federal Emergency Management Agency (FEMA) by varying levels of flood risk and flooding type. Special flood hazard areas are areas subject to a 1% annual chance to floods, or 100 year flood zones. Moderate and Minimal risk areas have a 0.2% chance of an annual flood and are also know as 500 year flood zones.
Boston, MA is located within Suffolk County. Its close proximity to the ocean make the Boston area more vulnerable to flooding. Mapping areas such as roads that are found within flood zones can help prepare for such events.
Methodology
Data for the analysis was provided and downloaded from MassGIS Datalayer webpage. The data for 100 year and 500 year flood zones were dissolved and clipped to Suffolk County. The area of land and road length affected by the two flood zones was then calculated.
Results
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Conclusions
Suffolk County has a greater scale of road length with a 1% chance of annual flooding but a greater scale of land has a 0.2% chance of annual flooding. The Boston Harbor area of Suffolk County has a greater extent of 500 year flood zones than any other area in the county. This is in large part due to its close proximity to the ocean.
