The GIS determines all the grid cells contributing runoff to a basin outlet, delineates
a bounding polygon around all the cells, and computes a drainage area.
Using the delineated watershed characteristics, input parameters for rainfallrunoff models can be extracted from the GIS environment. This automation of the
input file creation is one of the biggest benefits of using GIS-based automated
hydrologic modeling techniques and can eliminate errors associated with manual
data entry. In addition to the transfer of hydrologic input parameters, several
automated modeling systems can determine the hydrologic connectivity between
subbasins and stream reaches resulting in a watershed schematic. There are several
GIS tools that are readily available to perform these pre-processing steps to create
input file.
Automated hydraulic modeling typically focuses on the development of an input
file for a model and displaying model output in a GIS. The extraction of cross section
data and delineating floodplain boundaries can be automated in GIS environments.
Cross section information in the form of station-elevation data is the primary input
for most hydraulic models used for floodplain analyses. Automated hydraulic modeling tools extract cross section data from digital terrain data and format it for use with
industry-standard hydraulic models such as HEC-2 or HEC-RAS. Other hydraulic
parameters such as reach lengths, channel bank stations, and Manning’s roughness
coefficients can also be extracted from GIS data and written to an input file.
5 US Environmental Protection Agency Programs
The US Environmental Protection Agency (USEPA) is actively promoting and
assisting any individuals and organizations in this country in planning and executing
the geographic information system (GIS) and remote sensing (RS) activities [46–
53].
There are many USEPA applications that utilize locational information from the
Facility Registry Service (FRS) Geospatial Reference Tables. Any application that
displays facility points from the National Shapefile Repository or the EPA Spatial
Data Library System (ESDLS) is utilizing coordinates from the geospatial structures.
In addition to the maps displayed within the Envirofacts and FRS Queries Web
queries, these applications also make use of Facility Coordinate Information in the
FRS Geospatial Reference Tables.
My Environment is a GIS application that provides a wide range of federal, state,
and local information about environmental conditions and features in an area of an
engineer or planner’s choice.
The USEPA’s GIS Data Integration document describes the GIS data integration
process for collaboration. Engineers and planners are allowed to view some of the
very useful files [51].
The USEPA Geospatial Dataset contains data on wastewater treatment plants,
based on the agency’s Facility Registry Service (FRS) [50].
216
S. O. Darkwah et al.
a bounding polygon around all the cells, and computes a drainage area.
Using the delineated watershed characteristics, input parameters for rainfallrunoff models can be extracted from the GIS environment. This automation of the
input file creation is one of the biggest benefits of using GIS-based automated
hydrologic modeling techniques and can eliminate errors associated with manual
data entry. In addition to the transfer of hydrologic input parameters, several
automated modeling systems can determine the hydrologic connectivity between
subbasins and stream reaches resulting in a watershed schematic. There are several
GIS tools that are readily available to perform these pre-processing steps to create
input file.
Automated hydraulic modeling typically focuses on the development of an input
file for a model and displaying model output in a GIS. The extraction of cross section
data and delineating floodplain boundaries can be automated in GIS environments.
Cross section information in the form of station-elevation data is the primary input
for most hydraulic models used for floodplain analyses. Automated hydraulic modeling tools extract cross section data from digital terrain data and format it for use with
industry-standard hydraulic models such as HEC-2 or HEC-RAS. Other hydraulic
parameters such as reach lengths, channel bank stations, and Manning’s roughness
coefficients can also be extracted from GIS data and written to an input file.
5 US Environmental Protection Agency Programs
The US Environmental Protection Agency (USEPA) is actively promoting and
assisting any individuals and organizations in this country in planning and executing
the geographic information system (GIS) and remote sensing (RS) activities [46–
53].
There are many USEPA applications that utilize locational information from the
Facility Registry Service (FRS) Geospatial Reference Tables. Any application that
displays facility points from the National Shapefile Repository or the EPA Spatial
Data Library System (ESDLS) is utilizing coordinates from the geospatial structures.
In addition to the maps displayed within the Envirofacts and FRS Queries Web
queries, these applications also make use of Facility Coordinate Information in the
FRS Geospatial Reference Tables.
My Environment is a GIS application that provides a wide range of federal, state,
and local information about environmental conditions and features in an area of an
engineer or planner’s choice.
The USEPA’s GIS Data Integration document describes the GIS data integration
process for collaboration. Engineers and planners are allowed to view some of the
very useful files [51].
The USEPA Geospatial Dataset contains data on wastewater treatment plants,
based on the agency’s Facility Registry Service (FRS) [50].
216
S. O. Darkwah et al.