United States Department of Agriculture
Forest Service
Science
Rocky Mountain Research Station
Air, Water, and Aquatic
Environments Program
Providing scientific knowledge and technology to sustain
our nation’s forests, rangelands, and grasslands
B R I E F I N G
January 15, 2014
RIVER BATHYMETRY TOOLKIT
KEY FINDINGS
 The RBT is a suite of powerful free GIS tools that
have been built to automatically extract several
common stream metrics
from
high
resolution
DEMs.
BACKGROUND
Traditional techniques for describing and understanding aquatic habitat in streams have focused
on manual measurements of topography in short
channel reaches. New remote sensing techniques now allow high resolution digital mapping over much larger stream domains, but analyses of these larger data sets are difficult.
RESEARCH
Research Activity: The US Forest Service and
ESSA Technologies are developing a suite of GIS
tools, the River Bathymetry Toolkit (RBT), for
processing high resolution Digital Elevation
Models (DEMs) of channels.
Management Implications: The RBT makes it
possible to efficiently characterize in-stream and
floodplain geomorphology to support aquatic
habitat analyses and numerical models of flow
and sediment transport. The RBT is available for
free and is actively being developed and improved. RBT functionality includes the ability to:
Specific cross-sections can be viewed in detail with
the Cross Section Explorer in the RBT. This window shows the hydraulic geometry attributes of a
section- these data are also stored in an extractable data base file.
 Cut user-defined cross sections and longitudinal profiles through a DEM to define the bathymetry in each cross section.
 Compute hydrologic parameters such as wetted area, bankfull width, hydraulic radius, stream
gradient, and sinuosity
 Detrend a DEM to remove the longitudinal valley slope.
 Vary the water level in a detrended DEM to investigate the distribution of water depths inside
a stream and the extent of “off-channel” habitat still hydraulically connected to the main stem .
 Locate residual pools, which may be useful for identifying fish habitat.
 The RBT provides a spatially-explicit
view
of
stream habitat that allows
one to move from viewing
stream habitat as discrete
units (pools or riffles) to
seeing a stream as a spatially continuous set of
habitat features which fish
interact (such as depth,
substrate, and velocity).
 The RBT is a critical component of ongoing fishhabitat analyses.
MORE INFORMATION
The RBT allows users to quantify stream habitat metrics (such as water depth) from topographic features
captured by highly accurate DEMs produced from LiDaR surveys.
The RBT web site (www.fs.fed.us/rm/boise/
AWAE/projects/river_bathymetry_toolkit.shtml)
provides useful links to data, maps, methods
and related publications. For more information, please contact Jim McKean, USFS
Research Geomorphologist, (208)373-4383
or jmckean@fs.fed.us.
Keywords: channel mapping, aquatic habitat, stream hydraulic geometry, fluvial geomorphology
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