Tennessee Department of Transportation
John Schroer, Commissioner

GIS in TDOT Ecology

Through the use of geographic information systems (GIS), better decisions can be made at early stages of project development. GIS allows TDOT ecologists to get a “big picture” view of a project area with concerns to natural features and threatened and endangered species. Roadway alternatives can be examined for known streams, wetlands, and threatened or endangered species prior to actual field surveys, which expend both time and money. This enables TDOT to select preferred alternatives that cause the least environmental damage.

Used in conjunction with other concerns such as archaeological sites, historic properties, and building locations, GIS can provide a spatial representation of all the constraints faced by a proposed project. This will ensure that all of the issues will be addressed when an alignment is chosen.

Once these alternatives are selected, field surveys using a global positioning system (GPS) can record data for specific locations of natural resources. These field data can then be used with GIS to produce an accurate and detailed map of the features affected by the alignment.