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Environmental Sensitivity Index (ESI) 

Environmental Sensitivity Index (ESI) maps provide a spatial view of coastal resources that could be at risk in the event of an oil spill. ESI maps are created by integrating data from numerous sources including fish and wildlife species information, habitat types, and presence of human-use resources such as public beaches and parks. This information is used to classify shorelines on a scale from 1 to 10 based on the the sensitivity to oil spill impacts. ESI maps accompany a detailed report of resources at risk which summarize known habitats, locations, seasonality, and life stage of all fish and wildlife species which occur within the designated area. 

ESI maps are used during the planning process to identify vulnerable areas prior to an oil spill event. During a spill, ESI maps help prioritize response efforts in the most sensitive areas and identify the best protection strategies for the particular resources occurring within the spill area. 

Explore ESI maps online with the Interactive Map Viewer.

Download GIS data for ESI Maps from the GIS Data Downloads site.

View PDF versions of ESI Maps using the ESI Map Atlas.