Flood and Storm Tracker (FaST) Maps
These maps were created to help assess impacts on nonindigenous aquatic species distributions due to flooding associated with storms. Storm surge and flood events can assist expansion and distribution of nonindigenous aquatic species through connection of adjacent watersheds, backflow of water upstream of impoundments, increased downstream flow, and/or creation of freshwater bridges along coastal regions. These maps will help natural resource managers determine potential new locations for individual species, or to develop a watchlist of potential new species within a watershed.
One Pager NAS FaST
Initial FaST Maps are generated within days of a storm. How we do this.
Revised FaST Maps are generated once actual flooding data becomes available. See how.
Disclaimer: This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.
Hurricane images courtesy of NASA
The refined NAS FaST map enhancement provides information only on the locations with flooding conditions that could breach drainage divides. We utilize information on the relative flood height using the best available data from the USGS Water Science Centers including stream gages, storm surge gages, inundation maps (when available), and identified high water marks along with National Oceanic and Atmospheric Administration modeled storm surge. This information is combined with information on the elevation of the hydrologic units at the 8-digit level (HUC-8s) boundaries (drainage divides) identified from digital elevation models. The flood elevation data was mapped with the hydrologic units' drainage divide elevations to determine if the flooding conditions were of sufficient height to breach the boundary. These "connection points" are identified along the hydrologic units' boundaries.
Hydrologic units identified as being flooded and potentially connected as part of the refined NAS FaST map are established based on the best available data. This map may not include all flooded areas. The refined NAS FaST map focuses on the potential spread of nonindigenous aquatic species between hydrologic units and is not a map of flood inundation.