W.«.\t
tyitir*

SWViVtf,

Bedrock

v>EPA VELMA Eco-hydrological Model, Version 2.0

www.epa.gov/research

IderitifyingGreen Infrastructure for Enhancing Water Quality & Ecosystem Service Co-Benefits

Bedrock

Hydroiogica! & Biogeochemical Processes

•	Stream flow, infiltration, ET...

•	Plant and soil C and N dynamics...

•	Fate and transport of nutrients...
Ecosystem Services

•	Clean drinking water

•	Flood protection

•	Food and fiber production

•	Greenhouse gas mitigation
Habitat for fish and wildlife

VELMA
1 f

mum

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 has 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	-v

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.

Results

VELMA 2.0 has been validated for GI 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

U.S. Environmental Protection Agency

Office of Research and Development

Continued on back


-------
Simulation & visualization of tradeoffs among ecosystem services for alternative land use & climate scenarios

Ecosystem service tradeoffs for four alternative
forest management scenarios, 2000 - 2200

Blue River Watershed, Oregon

«H

No Harvest
Plan

L



Industrial
Forest Plan

li

Northwest
Forest Plan

Ajk

Landscape
Mgmt. Plan

¦ Timber Production
B Total Ecosystem C

~	C sequestration rate

~	GHG netflux

~	Stream Flow

~	Stream Nitrogen Load

~	Early Serai Habitat

~	Late Serai Habitat

McKane et al. 2014a

buffers can fail, depending upon
contaminant loads, soil properties,
changes in climate and other factors.

VELMA 2.0 has 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
service assessments in a number of

ways:

•	Provides advanced visualization
capabilities for assessing the
effectiveness of GI strategies for
improving water quality of streams,
rivers and estuaries.

•	Supports quantification of ecosystem
service co-benefits and tradeoffs
associated with alternative GI and
climate change scenarios.

•	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).

•	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 fiiel 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.

Contact

Bob McKane, PhD

VELMA Team Lead

USEPA-ORD-NHEERL-WED

Corvallis, OR

541-754-4631; mckane.bob@epa.gov

EPA clearance number: ORD-010524

U.S. Environmental Protection Agency

Office of Research and Development

Page 2


-------