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science in ACTION
BUILDING A SCIENTIFIC FOUNDATION FOR SOUND ENVIRONMENTAL DECISIONS
Safe and Healthy Communities
Research Program
Task 2.1.5.2.4
OpenTERRAworks GIS-Tool
Supporting Predictive Analysis
of the Future Before it Happens
OpenTERRAworks - A 2D/3D Landscape Design Tool
An open, Dot'Spatial'based toolset supporting comparative baseline and futures scenario modeling.
For those who can't wait for satellites to tell us the future
Change Happens!
Human activities involving significant
terrain alteration (e.g., earthworks
operations associated with mines,
urban development, landslides) can
lead to broad-ranging changes in the
surrounding terrestrial and aquatic
environments. Potential aesthetic
impacts can be associated with
modified relief, soils, and/or change
in land cover. Additionally, changes
can be seen in spatiotemporal rates
of surface runoff and erosion;
rerouted flow paths; impacts to
water quantity and quality; and
species and ecosystem composition.
The General Problem
Due to a lack of open "GIS" design
tools, most assessors are basically
"waiting for the future to predict it".
Given opportunity, assessors would
rather create the detailed landscape
views needed to model it today.
In design and in decision-making, the.
brobkm is that the FUTURE IS NOW.
The OpenTERRAworks (OTW) Tool
A multi-scale Geographical
Information System (GIS) toolset to
expand the technical capacity of
communities and the USEPA to
predict hillslope- to watershed-scale
effects of proposed, alternative, and
legacy landscape designs involving
significant terrain modification.
Present
Baseline
Landscapes
H2w
Landscape future
Past
Figure 1. OpenTERRAworks Software
System Design Overview.
A product of ORD's SHC Research
Program, the OpenTERRAworks
Software system is geared for the
production of modified datasets
representing actual or proposed
landscape changes (see Figure 1).
.... OTW is a "substitution" design
pattern for readily modifying the large
and many datasets that modeling
systems consume.
Specifically, the OTW system allows
users to more easily modify datasets
to represent changes in terrain
elevations, soils, land use/land cover,
and hydrography. These data capture
many key landscape features needed
to understand and predict associated
environmental outcomes.
OTW is not a model; rather, OTW
helps generate data necessary to
represent landscape changes in
models, and other analytical
frameworks; to evaluate potential
impacts from 2D/3D landscape
change, ideally, before it happens.
Figure 2 depicts OTW's workflow.
U.S. Environmental Protection Agency
Office of Research and Development
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Get the Data!
By offering default-scale baseline
design data for the conterminous
U.S., OTW creates a common starting
point for analysis. Many models rely
on the following input datasets that
characterize landscapes in support of
hydrologic and other evaluations:
• The National Land Cover Database
(NLCD) is a land cover classification
scheme applied across the United
States at a spatial resolution of 30
meters (USGS, 2012a).
• The Soil Survey Geographic
database (SSURGO) provides a
polygon-based inventory of soils
and non-soil areas and is the most
detailed available dataset across
the United States.
Consume baseline spatial datasefs:
terrain (DEM), hydrography, soils, and
land use
Characterize landscape changes:
terrain cutTill, modffled hydrography,
soils and land use changes
Produce modified terrain, hydrography,
land use, and soils datasets to support
comparative analysis through
iemTechnologies and other platforms
Figure 2: The OpenTERRAworks workflow and relation to downstream analytics.
• Digital Elevation Model (DEM)
datasets are digital representations
of terrain elevations.
• The National Hydrography Dataset
(NHDPlus) contains an
interconnected network of surface-
water features including lakes,
streams, and rivers, with extensive
descriptive attributes.
OTW focuses on automated import
of the standard data sources listed
above and their subsequent
modification to represent landscape
modifications.
Or Use Your Own Data!
OTW also has the flexibility to work
with datasets other than standard,
default data sources provided. The
key datasets listed can be substituted
with different source and/or finer-
resolution data systems the user may
also have available for analysis.
Have LIDAR?-Will Travel
The OTW system can import and
work with alternative datasets as
long as they conform to the required
data structures: floating point raster
for terrain elevations; discrete-
valued raster for land use; and
continuous polygon for soils.
For example, a given site may have
been characterized at a finer
resolution and/or with more
accuracy than standard datasets
(e.g., through LIDAR or field surveys).
Such data can be imported for direct
and similar uses. As the expression
goes - have suitcase, will travel --
OTW is equally ready to go - to begin
posing alternative futures derived
from user-supplied baseline datasets.
Start with a Workspace!
The basic organizational system of
OTW is the workspace which is
comprised of one or more related
sites. Each site is described by one or
more design paths made up of
sequential phased designs and/or
branched designs (Figure 3).
Figure 3: OTW "site" phasing and branching.
Branched designs allow divergence
into alternative design paths from a
single predecessor design in order to
represent alternative design options.
The predecessor design for each site
design is referred to as its basis
design. A design set is a site's
collection of all site designs.
U.S. Environmental Protection Agency
Office of Research and Development
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Draw a picture to build a site!
OTW strives to simplify the process
of building a site and representing
landscape changes, whether it be
defining a site area or assisting the
user in creating a surface coal mine
contour "cut". Creating a site simply
involves clicking on the map to
delineate the site area (Figure 4).
Figure 4: Building a site.
Once a site is named, described, and
drawn, the relevant standard (or
other user) data is downloaded and
stored for later usage/modification.
All tools that interact with the map
work on this same "click-to-build"
paradigm, with supporting panels to
enter relevant metadata.
Use OTW to Modify Landscapes
OTW provides tools (Figure 5) to
assist with several design tasks:
corehole interpolation; planar
surface creation for coal bed
interfaces; contour cuts; specification
of area cuts; definition of valley fills;
as well as other spatial methods.
By using OpenTERRAworks' design
tools, a natural progression of the
site from baseline all the way to its
finished state can be created.
OTW is not just for mining analysis.
The tool is seen to easily serve 3D
design needs for golf-course or
airport "siting" evaluation, as well as
post-event analysis of earthquake or
volcanic eruptions. "Designed in",
but not yet fully implemented,
expanded "2D" change scenario
modeling, and a "module"
envisioned for retrospective analysis,
aims to soon deliver unchartered
facilitation in ease of constructing
comparative 2D/3D analysis of the
post, present, and multiple/t/tt/res.
Visualize the results!
In addition to being
able to see changes
to the site as you
draw them, OTW
also provides a 3D
viewer (Figure 6) to
further enhance
the user's
visualization of
each designed
landscape.
Potential future land uses cannot be
easily simulated without undertaking
the significant effort to develop the
datasets needed to describe future
landscapes. Accordingly, it has
remained difficult or impossible for
many assessors to predict both
impacts and benefits from proposed,
future land uses that impart
significant landscape 2D/3D change.
To support predictive analyses given
these challenges, assessors need
tools that facilitate science-driven,
integrated assessment (hydrological,
hydroecological); tools that readily,
and realistically, pose and track
spatiotemporal changes in terrain,
and associated modifications to land
cover, soils, and hydrography. OTW
holds the promise to be that toolset.
Figure 6: 30-Visualization of a post-"cut" operation at the site.
Figure 5: Area cut interface - coal seam.
Recreate the past, construct the
present, and envision the future!
Models capable of predicting impacts
from landscape modifications (e.g.,
process-based watershed models)
rely heavily on satellite data or aerial
based sensors (e.g., LIDAR) to
characterize terrain, land cover, soils,
and hydrography (i.e., catchments
and stream networks).
Yet, datasets are often only readily
available in forms that describe
today's or yesterday's conditions.
Join the community!
The OTW core is intended as a public
domain project; an open, publically
available tool that seeks to form a
vibrant community of interested
parties; a resource to meet the
current and future needs of
interested parties across a wide
spectrum of community users.
For more information, contact:
Justin Babendreier,
babendreier.justin@epa.gov
ORD/NERL/ERD - Athens, GA 30605
U.S. Environmental Protection Agency
Office of Research and Development
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