&EPA
www.epa.gov/research
science in ACTION
NNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE
VELMA ECO-HYDROLOGICAL MODEL, VERSION 2.0
Identifying Green Infrastructure for Enhancing Water Quality & Ecosystem Service Co-Benefits
Background
Sustainable supplies of clean water
are vital to human health, local
economies, recreational
opportunities, and protection of
aquatic habitat. Increasing pressures
from population growth and land use
change have compromised water
quality of many U.S. rivers and
estuaries. Projected changes in
climate are expected to further
impact water resources. As a result,
many communities are exploring
green infrastructure (GI) options for
protecting water quality.
GI involves the establishment of
riparian buffers, cover crops,
constructed wetlands, and other
measures to intercept, store and
transform nutrients, toxics and other
contaminants that might otherwise
reach surface and ground waters.
Although many communities and
landowners are already using or
planning to invest in GI. sufficient
data often do not exist to make
informed decisions about where,
how much and what kinds of GI will
be required to meet water quality
goals at local and regional scales.
In particular, it lias been difficult to
identify general rules that can be
applied to any given location or set
of conditions. Social and economic
considerations also cloud the picture,
as stakeholders are often in
disagreement on the effectiveness
and need for riparian buffers.
Tradeoffs in land-use (e.g.
agricultural demand vs. water
quality) often drive the debate and
decision making process. Thus, there
is a clear need for scientifically
defensible tools that stakeholders
can use to predict trade-offs and
estimate benefits of GI options
appropriate for specific regions,
habitats and conditions.
r	"\
VELMA predicts the
effectiveness of alternative
green infrastructure scenarios
for protecting water quality,
and also estimates potential
ecosystem service co-benefits
and tradeoffs.
J
Approach
We developed an enhanced version
(2.0) of the VELMA eco-
hydrological model to help
communities, land managers, policy
makers and other decision makers
assess the effectiveness of GI
options for improving water quality
of streams, rivers and estuaries.
VELMA (Visualizing Ecosystem
Land Management Assessments)
predicts how natural and engineered
GI options control the fate and
transport of water, nutrients and
toxics across multiple spatial and
temporal scales - from plots to
basins, from days to centuries.
VELMA also quantifies how
different GI strategies affect
ecosystem service co-benefits and
tradeoffs - that is, the ecosystem's
capacity to simultaneously provide
clean water, flood control, food and
fiber, climate (greenhouse gas)
regulation, fish and wildlife habitat,
etc.
These GI model enhancements
include (1) major changes to the
biogeochemical and hydrological
submodels; (2) addition of a
graphical user interface with
powerful visualization capabilities;
(3) a detailed user manual to assist
novice and experienced model users
in developing scenarios and
applying VELMA for planning,
policy and scientific applications;
and (4) recoding the model in Java
Eclipse to better support open source
(community) model development.
(continued)
VELMA
Visualizing Ecosystem Land Management Assessments
Ecohydrological Processes
•	Hydrological: stream flow & temperature,
evapMrarispiratian...
•	Biogeochemical: cyding. decomposition,
sequestration & transport of carbon,
nutrients & toxics in ptants & soils
•	Drivors of change: cinsate, fire, harvest,
fertilization, graing, urbanisation
1
U.S. Environmental Protection Agency

-------
~T'. .z,-. «.-» _
:• -i, • ^r^B^s^r-.
r^r -
Habitat visualization for
120 km2 Blue River Watershed
Ecosystem service tradeoffs for four alternative
forest management scenarios, 2000 - 2200
Blue River Watershed, Oregon
No Harvest
Plan
I
Industrial
Forest Plan
ll

Northwest
Forest Plan
.
i
Landscape
Mgmt. Plan
¦ Timber Production
B Tota I Ecosystem C
~	C sequestration rate
~	GHG netflux
O Stream Flow
~	Stream Nitrogen Load
~	Early Serai H abitat
~	Late Serai Habitat
McKaneetaL2G14a
Results
VELMA 2.0 lias been validated for
G1 in the Pacific Northwest and
Chesapeake Bay (Abdelnour et al.
2011, 2013; McKane et al. 2014a,
b). These applications focus on the
use of riparian buffers, cover crops
and other GI practices in agricultural
and forest watersheds. Results
illustrate how stream nutrient loads
can be significantly reduced by
locating riparian buffers in areas
with shallow groundwater flow, and
by maintaining buffer widths above
nutrient-specific "breakthrough'
thresholds. Results also illustrate
how once-effective riparian buffers
can fail, depending upon
contaminant loads, soil properties,
changes in climate and other factors.
VELMA 2.0 lias also been used to
quantify ecosystem service co-
benefits under alternative GI
strategies, including greenhouse gas
mitigation, enhancement of fish and
wildlife habitat, among others
(McKane et al. 2014b).
Significance
VELMA 2.0 advances GI and
ecosystem sendee assessments in a
number of ways:
(1)	Provides advanced visualization
capabilities for assessing the
effectiveness of GI strategies for
improving water quality of streams,
rivers and estuaries.
(2)	Supports quantification of
ecosystem service co-benefits and
2
tradeoffs associated with alternative
GI and climate change scenarios.
(3)	Provides a transferable
framework for making consistent
comparisons of GI benefits across
habitats and ecoregions. The
aforementioned GI demonstrations
for the Pacific Northwest and
Chesapeake Bay watersheds are
included with the VELMA 2.0
package (McKane et al. 2014a).
(4)	VELMA is being linked with
other tools, such as the BlueSky and
BenMap air quality models, to better
understand ecological, economic and
human health tradeoffs associated
with alternative decision scenarios,
such as when and where to conduct
rangeland prescribed fires for
particular fuel load and atmospheric
conditions (collaborative project
with EPA Region 7).
VELMA Users
The VELMA 2.0 software and user
manual are designed for several
kinds of user groups, based on
experience and need:
•	Group 1: User describes
questions and goals, VELMA
team does the rest. Example:
EPA clients (Regions, Office of
Water, Office of Air and
Radiation) who require
information on potential effects of
a policy change on water quality
and ecosystem service tradeoffs.
•	Group 2: User assembles GIS
data, creates GI and climate
scenarios, runs simulations and
analyzes data. VELMA team
provides model input files and
calibrated parameters.
Example: federal and state land
managers, tribes, watershed
councils and other community
groups with sufficient GIS
expertise.
• Group 3: User works
independently to assemble model
input files, calibrate parameters,
and analyze model output.
Example: academics and other
professionals with expertise in
hydrology, biogeochemistry and
GIS methods.
References:
Abdelnour et al. (2011). Catchment hydrological
responses to forest harvest amount and spatial
pattern. Water Resources Research, 47(9).
Abdelnour et al. (2013). Effects of harvest on carbon
and nitrogen dynamics in a Pacific Northwest forest
catchment. Water Resources Research, 49(3).
McKane et al. (2014a). Enhanced version of
VELMA eco-hydrological modeling and decision
support framework to address engineered and
natural applications of green infrastructure for
reducing nonpoint inputs of nutrients and
contaminants. Report ORD-010080, US EPA,
Washington, DC.
McKane et al. (2014b). Sustainable and Healthy
Communities Pacific Northwest Demonstration
Study. Report ORD-007386, US EPA, Washington,
DC.
VELMA WEBSITE:
https ://www.epa. gov/water-research/visualizing-
ecosystem-land-management-asses sments-velma-
model-20
EPA 601-F-16-001
CONTACT:
Bob McKane, PhD, VELMA Team Lead, USEPA-
ORD-NHEERL-WED, Corvallis, OR
541 -754-4631; mckane.bob@epa.gov
October 10, 2014
U.S. Environmental Protection Agency

-------