Challenges in Sustainability | 2016 | Volume 4 | Issue 1 | Pages 39–53
DOI: 10.12924/cis2016.04010039
ISSN: 2297–6477
Challenges in
Sustainability
Research Article
Siting Urban Agriculture as a Green Infrastructure Strategy for
Land Use Planning in Austin, TX
Charles M. Rogers* and Colleen C. Hiner
Department of Geography, Texas State University, San Marcos, TX, USA
* Corresponding author: E-Mail: Cmr138@txstate.edu; Tel.: +1 4794458334
Submitted: 1 February 2016 | In revised form: 19 July 2016 | Accepted: 19 July 2016 |
Published: 22 August 2016
Abstract:
Green infrastructure refers to a type of land use design that mimics the natural water cycle by
using the infiltration capacities of vegetation, soils, and other natural processes to mitigate stormwater
runoff. As a multifunctional landscape, urban agriculture should be seen as a highly beneficial tool for urban
planning not only because of its ability to function as a green stormwater management strategy, but also
due to the multiple social and environmental benefits it provides. In 2012, the city of Austin adopted a major
planning approach titled the “Imagine Austin Comprehensive Plan” (IACP) outlining the city’s vision for
future growth and land use up to 2039. The plan explicitly addresses the adoption of green infrastructure as
a target for future land use with urban agriculture as a central component. Addressing this area of land use
planning will require tools that can locate suitable areas within the city ideal for the development of green
infrastructure. In this study, a process was developed to create a spatially explicit method of siting urban
agriculture as a green infrastructure tool in hydrologically sensitive areas, or areas prone to runoff, in east
Austin. The method uses geospatial software to spatially analyze open access datasets that include land
use, a digital elevation model, and prime farmland soils. Through this method a spatial relationship can be
made between areas of high surface runoff and where the priority placement of urban farms should be sited
as a useful component of green infrastructure. Planners or geospatial analysts could use such information,
along with other significant factors and community input, to aid decision makers in the placement of urban
agriculture. This spatially explicit approach for siting potential urban farms, will support the integration of
urban agriculture as part of the land use planning of Austin.
Keywords: GIS; green infrastructure; urban agriculture; urban planning; watershed protection
1. Introduction
1.1. Green Infrastructure and Urban Agriculture
The federal Clean Water Act (CWA) of 1972 provided a
basic framework for the regulation of pollutant discharges
with the intent of protecting water quality and human health
in the United States (U.S.) [
1
]. To further the protective
benefits of the CWA, the Environmental Protection Agency
(EPA) enacted its Combined Sewer Overflow Control Policy
in 1994 [
2
]. This policy initiative established guidelines by
which municipalities could better manage environmentally
harmful stormwater pollution events that occurred as a re-
sult of infrastructural challenges in handling both sanitary
sewage and stormwater runoff in the same sewer system
during precipitation events. In response, many cities im-
c
2016 by the authors; licensee Librello, Switzerland. This open access article was published
under a Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/).
librello
plemented green infrastructure measures to help mitigate
urban stormwater runoff as an alternative to expensive wa-
ter main upgrade projects. Green infrastructure can be
defined as the management of runoff through the use of
natural systems, or engineered systems that act as nat-
ural systems, to allow stormwater to infiltrate the ground,
recharging the water table and decreasing run-off. Accord-
ing to the EPA, Green infrastructure uses vegetation, soils,
and natural processes to manage water and create health-
ier urban environments. At the scale of a city or county,
green infrastructure refers to the patchwork of natural ar-
eas that provides habitat, flood protection, cleaner air, and
cleaner water. At the scale of a neighborhood or site, green
infrastructure refers to stormwater management systems
that mimic nature by soaking up and storing water [
3
]. While
this definition of green infrastructure is structured on water
management, there are broader definitions of green infras-
tructure that focus on aspects such as clean air, wildlife
habitat, and preservation of forests and grasslands.
With the industrialization of our food systems, most
cities, whether intentionally or not, have developed in such
a way that farms have become incompatible with the urban
environment. There is, however, a tremendous amount of
resurgent interest in urban farming and community garden-
ing across the country. In general terms, urban agriculture
refers to “the growing, processing, and distribution of food
and nonfood plant and tree crops and the raising of live-
stock, directly for the urban market, both within and on the
fringe of an urban area” ([
4
], p. 2500; [
5
], p. 4). As evi-
denced by the recent growth of municipal urban agriculture
land inventories as a method to integrate urban agriculture
into sustainable land management policy [
6
], we can infer
that municipalities value the multi-beneficial attributes that
urban agriculture offers. Urban agriculture has been char-
acterized as a multifunctional land use because, through
its versatility as a landscape, it offers a range of benefits
to densely populated areas [
4
]. For example, the ecolog-
ical functions of urban agriculture provide environmental
benefits in the form of biodiversity, nutrient cycling (com-
post), or wastewater re-use (stormwater and greywater);
the cultural functions improve the quality of a neighborhood
or community through its visual appeal, recreational use,
or the provision of rare foods to immigrant communities;
the socio economic functions provide access to nutritious
fresh produce for underserved communities in food deserts
facing obesity and diabetes [4].
In fact, evidence suggests that incorporating appropriate
types of urban agriculture into the urban environment will
greatly improve the overall sustainability of U.S. cities [
4
,
7
].
The EPA, in collaboration with experts from academia, state
and local governments, and nonprofits, released a general
listing of the benefits of urban agriculture:
Increases surrounding property values, beautifies va-
cant properties, increases a sense of community, and
provides recreational and cultural uses [8].
Increases infiltration of rainwater, reducing stormwa-
ter overflows and flooding, decreases erosion and
topsoil removal, improves air quality, and reduces
waste by the reuse of food and garden wastes as
organic material and compost [8].
Increases physical activity and educates new garden-
ers on the many facets of food production from food
security to nutrition and preparation of fresh foods [
8
].
While the positive ecological and environmental impacts
of urban agriculture have been acknowledged, minimal re-
search has been conducted to determine the feasibility of
urban agriculture as a green infrastructure strategy to man-
age stormwater. Green infrastructure strategies include
a list of practices that have been studied and quantified,
making their engineering and performance outcomes pre-
dictable and reliable [
3
]. A lack in such quantification, or of
carefully researched sets of best management practices,
leads to a further lack in the promotion of urban agriculture
as a green infrastructure strategy. As Dunn ([
9
], p. 58)
argues: “Being able to quantify the effectiveness of green
infrastructure on a small scale is one way to promote regula-
tory and enforcement acceptance, which thereby enhances
its appeal to city officials”. As a productive, multifunctional
landscape, urban agriculture offers answers to complex
infrastructural challenges that are facing many cities.
1.2. Urban Agriculture Land Inventories
Over the last decade a variety of municipalities have begun
the process of inventorying and assessing land to determine
the potential for a broad range of urban agricultural initia-
tives. This effort is driven by a diverse range of community
stakeholders, each with an interest in growing food locally,
including capturing the social and environmental benefits
urban agriculture provides. Yet, despite the realized and
potential benefits for individuals and communities, urban
agriculture is largely overlooked in urban and regional plan-
ning [
4
,
10
]. Instead of considering opportunities to preserve
farmland or to integrate it as part of a land use management
strategy in urban environments, agricultural landscapes are
often considered by land use planners as areas for future
development [4].
As part of the urban planning process, land inventories
have been used and recognized as a basic tool for land
suitability and site selection [
11
]. Many municipalities and
researchers are now employing this tool to promote urban
agriculture, integrating it into public policy and planning as a
land management strategy. Horsts’ (2011) paper “A Review of
Suitable Urban Agriculture Land Inventories” provides a brief
overview of urban agriculture land inventories in various cities
[
12
]. Inventories have been performed in Portland, Vancou-
ver, Seattle, Cleveland-Cuyahoga County, Detroit, Chicago,
Toronto, New York City, Cincinnati, Oakland, and San Fran-
cisco [
12
]. Some of the inventories primarily focus on public
vacant land and some open up their inventory to include
private lands or residential lands such as lawns or rooftops.
Decisions made as part of urban agricultural land in-
ventories typically require the input of multiple criteria in-
volving social, economic, and environmental considerations
40
[
6
,
13
,
14
]. The success of multiple criteria decision making
depends on an array of knowledgeable stakeholders mak-
ing informed decisions [
15
]. Using this model, inventories
rely upon the explicit use of an advisory committee with rep-
resentation from municipal staff, non-profit organizations,
urban gardeners, and academic researchers. Many inven-
tories emulate the Portland model, wherein an advisory
committee guided the inventory throughout the process,
particularly in establishing evaluation criteria and reviewing
preliminary results. Mendes et al. [
6
] points to Portland’s
inventory as more successful when compared to Vancouver
due to the way Portland engaged many community part-
ners throughout the entire process, from design to imple-
mentation, while Vancouver lacked community involvement.
Mendes et al. [
6
] suggests this represents what the schol-
arly literature identifies as a “networked movement”, where
participation in local decision making is inclusive and citi-
zen engagement is fully accepted, similar to Arnstein’s [
16
]
highest rungs in the ladder of citizen participation (Partner-
ship, Delegated Power, Citizen Control). Likewise, Oakland
established a Community Advisory Committee throughout
the project that provided citizen input in a number of ar-
eas: the location of potential sites, criteria for selection of
potential sites, and feedback on what type of information
would be useful in the finished inventory [
17
]. The best as-
set mapping has been described, especially in the case of
urban agricultural land inventories, to be a multi-stakeholder
process for action planning and policy design [4,6,18].
Many of the inventories have involved multiple stake-
holders in research and analysis phases, but have been
less inclusive when performing technical analysis includ-
ing Geographical Information System (GIS), aerial imagery
assessment, and site visits or ground-truthing [
19
]. The
key actors during this phase of inventory development have
been municipal staff, experts from food policy councils and
non-profits, and students [
12
]. The partnership among
stakeholders from the city governments and student re-
searchers from local universities has created synergistic
opportunities. In Portland, Vancouver, Oakland, Seattle,
and Cleveland among others, graduate students worked
in partnerships with local municipalities to complete the
inventory, thereby gaining valuable experience while the
respective cities received cost-effective results.
Generally, the vacant land inventories followed a frame-
work of identifying vacant or open land by ownership type,
categorized as public or private, assigning suitability criteria,
then eliminating the unsuitable sites and highlighting the
best. Within this generalized framework, most inventories
created suitability criteria for urban agriculture addressing
physical and socioeconomic factors, assigned a ranking or
scoring system for criteria, presenting the study results as
publicly available reports [19].
The technical work for most inventories made use of
one or a combination of methods including aerial photo
assessment, GIS analysis, remote sensing, and site visits.
Some efforts relied extensively on GIS analysis or remote
sensing as in New York and Philadelphia [
20
,
21
]. The
potential exists for expanding the use of GIS and remote
sensing for urban agricultural land inventories from other
approaches developed by urban land use researchers. For
example, Myeong et al. [
22
] developed vegetation indexes
that estimate vegetation coverage and bare soil, criteria
that usually requires labor-intensive visual assessment, us-
ing multi-spectral and hyper-spectral data to identify urban
green areas [
21
]. Other inventories have made use of the
satellite imagery from the National Agricultural Imagery Pro-
gram (NAIP) overlaid onto the GIS city parcel data of vacant
land in order to select parcels containing potentially arable
land [
23
]. A more specific use of geospatial data in the Hal-
ifax, Canada inventory used the LiDAR data to model sun
exposure, an important aspect of most inventories suitability
criteria for potential urban agricultural sites [23].
As the practice of inventories is evolving, there are ar-
eas for improvement. In particular, many authors noted
limitations because of incomplete data, limited availability
of data, and frequency of updated data [
13
,
21
,
23
,
24
]. A
common limitation expressed by researchers stemmed from
low resolution and accuracy of the aerial imagery that re-
sulted in possible visual interpretation errors [
13
,
23
]. As
a result, researchers advised that post-analysis ground-
truthing of potential sites would be necessary to quality
check geospatial analysis [
13
,
23
]. Additionally, establish-
ing a measure of community support is also an area that
many inventories acknowledged needed further research
to identify variables such as cultural preferences, skills and
willingness, demand, resources, and the presence of local
leaders [
21
,
24
,
25
]. Inventories with community advisory
committees also noted that site visits, community outreach,
and consultation with city staff are necessary to evaluate
characteristics like soil quality, community interest, and se-
curity [
6
,
14
,
23
]. Soil quality, in particular, is an issue in
many urban areas that was recognized by most inventories
as an area for further research and analysis. In Oakland, for
example, the completed inventory inspired further research
about lead (Pb) contamination in the soil of potential urban
agricultural sites. This research assessed Pb levels at over
a hundred different sites identified in the inventory [26].
Beyond land identification, land inventories have been
an effective tool to integrate urban agriculture into urban
policy and planning as a land management strategy [6]. As
a part of the planning process land inventories can identify
opportunities for urban agriculture initiatives that result in
positive changes. Some impacts have included increasing
awareness and political support for urban agriculture, ad-
vancing social and ecological sustainability, and enhancing
public involvement [
6
,
17
]. For example, Toronto, Seattle,
and Portland experienced notable changes resulting from
vacant land assessments. In Toronto, local zoning regula-
tions and guidelines were altered to help guide an increase
in urban agriculture [
19
]. In Seattle and Portland, the col-
laborative process increased community involvement and
inclusion of urban agriculture into city sustainability planning
[
6
]. Stakeholders have also built upon these assessments
and conducted more targeted in depth studies that relate
41
to issues of public health, economic development, food
security, and environmental sustainability [
19
]. As a tool,
land inventories do not have to function in isolation and can
be employed in conjunction with other strategies, such as
surveys or scenario planning, to advance municipal goals
such as stormwater management, reducing carbon emis-
sions, increasing food access, and supporting workforce
development [6].
Urban agriculture land inventories have been a useful
step for many cities in evaluating the potential for urban agri-
culture, though the process and resulting impacts are unique
to each city. The type of parcels considered, criteria applied,
and stakeholders involved differ depending on the objective.
The delineation of potential urban agriculture sites is only a
preliminary step in a long process of mapping the potential
of urban agriculture in a city [
23
]. That being said, such
demarcations can be a useful starting point as cities begin
to incorporate urban agriculture into community planning.
The tools involved with a land inventory have the potential
to facilitate participatory planning by bringing together com-
munity participants such as local residents, food activists,
academic researchers, and farmers with city planners and
government officials, in an effort to better plan and man-
age land use [
4
]. Nevertheless, the politics of negotiating
competing uses of land is inherently complex and difficult.
The viability of utilizing urban agriculture land inventories for
planning will depend upon identifying and negotiating the
varied interests of multiple stakeholders [23].
1.3.
Can Urban Agriculture identify as Green Infrastructure
in Austin, TX?
In 2012, the City of Austin adopted a major planning
approach titled the Imagine Austin Comprehensive Plan
(IACP) that outlines the vision for future growth and land
use in the city until 2039. The plan explicitly addresses the
adoption of green infrastructure as a targeted future land
use with urban agriculture specifically being included as a
component of the green infrastructure network.
The IACP identified eight priority programs, ranked in
order of importance, which will guide policy and implemen-
tation of the plan. The fourth priority proposes the use of
“green infrastructure to protect environmentally sensitive
areas and integrate nature into the city” [27]:
1. Invest in a compact and connected Austin.
2. Sustainably manage our water resources.
3.
Continue to grow Austin’s economy by investing in our
workforce, education systems, entrepreneurs, and lo-
cal businesses.
4.
Use green infrastructure to protect environmentally
sensitive areas and integrate nature into the city.
5. Grow and invest in Austin’s creative economy.
6.
Develop and maintain household affordability through-
out Austin.
7. Create a Healthy Austin Program.
8.
Revise Austin’s development regulations and pro-
cesses to promote a compact and connected city.
The building block actions listed as methods to imple-
ment the green infrastructure priority program include several
references to urban agriculture (below; emphasis added):
Integrate citywide and regional green infrastructure to
include such elements of preserves and parks, trails,
stream corridors, green streets, agricultural lands,
and the trail system into the urban environment and
the transportation network [27].
Incentivize appropriately-scaled and located green
infrastructure and public spaces, such as parks,
plazas, greenways, trails, urban agriculture and/or
open spaces in new development and redevelopment
projects [27].
Expand regional programs and planning for the pur-
chase of conservation easements and open space
for aquifer protection, stream and water quality pro-
tection, wildlife habitat conservation, and sustainable
agriculture [27].
Extend existing trail and greenway projects to create
an interconnected green infrastructure network that
includes such elements as preserves and parks, trails
stream corridors, green streets, greenways, and agri-
cultural lands that link all parts of Austin and connect
to nearby cities [27].
Permanently preserve areas of the greatest environ-
mental and agricultural value [27].
This study looks at east Austin where there is 1) an
established urban and peri-urban farm presence and 2)
high future development potential of agricultural land due
to the Austin-Round Rock Metro Area’s rapid growth (110
people per day) [
28
] and lack of land use constraints lead-
ing to urban sprawl [
28
]. Since the late 1990s, the City of
Austin has viewed the eastern side of the metro area as a
prime area of growth and development. Without an urban
growth boundary most of what the city has determined as
the “desired development zone” (DDZ) falls into much of
east Austin (Figure 1) and beyond into the Austin’s Extrater-
ritorial Jurisdiction (ETJ). The opening of the SH130 tollway,
conceived of as a north-south alternative route to interstate
35 on the east side of Austin, has further opened up large
areas of available land for new jobs, housing, and services
for Austin’s rapidly growing population. The Imagine Austin
plan conceives of growth corridors around the city, with the
SH130 corridor representing one of those growth corridors
in east Austin. According to 2012 land use data from the
City of Austin, 94,961 acres of undeveloped land, much of
it in agriculture, existed in the suburban portion of the DDZ.
Information from the 2015 State of the Food System Report,
released by the City of Austin’s Office of Sustainability, put
the loss of farmland each day in Travis County at 9.3 acres
and a 25% loss in farmland over the last 11 years [29].
42
Figure 1.
The Decker Creek and Elm Creek Watershed
study areas, located in Austin, Texas in Travis County, re-
side completely in the Suburban DDZ, an area promoted
for growth and development by the City of Austin.
Furthermore, the hydrologic environments in east Austin
are already under much pressure as a result of being located
downriver from the impervious cover of the central business dis-
trict and at the bottom of several highly urbanized watersheds,
effectively making east Austin the hydrologic drain for the city
[
30
]. The creeks and watersheds within east Austin have ex-
perienced significant erosion problems and flooding associated
with the increasing development and impervious cover seen
upstream over the last half century [
30
]. Further exacerbating
the erosion problems have been urban development patterns in
the suburban DDZ that situated buildings on small lots close to
the creeks. The Austin City Council itself has underscored the
potential implications of increasing development and its effect
on eastern watersheds:
The eastern watersheds, with broader floodplains and more
erosive soils, pose unique challenges to creek and floodplain
protection. Development is currently being placed in close prox-
imity to erosive creek banks in headwaters areas and creating
future problems requiring significant and unsustainable public
expense to maintain and repair. This development will likely
accelerate as build-out proceeds along SH-130 [31].
As a response to city-wide watershed threats, the City Coun-
cil updated the watershed protection policies in 2013 with Phase
One of the new Watershed Protection Ordinance (WPO). The
new WPO increased stream buffers and erosion hazard zones
to ensure development is not built to close to waterways for over
400 miles of smaller headwater streams [
32
]. Phase Two of
the WPO began in January 2015 with a Green Infrastructure
Working Group as part of the Citys land development code
rewrite process, called CodeNEXT, to discuss how to achieve
the Imagine Austin goals of integrating nature into the city and
creating complete communities through revisions to our zoning
and environment codes [
32
]. Currently, green infrastructure
techniques in the Watershed Departments manual for best man-
agement practices include rain gardens, bio- filtration areas, and
vegetative filter strips; however, there is no reference to urban
agriculture as a green infrastructure strategy for new develop-
ment or as a stormwater management strategy in the city.
Nevertheless, within the last twenty years there has been
a proliferation of urban agriculture in east Austin. A variety of
urban agriculture exists in the city, ranging from community gar-
dens to small market farms (defined as farms operating on less
than one acre within the citys full jurisdictional boundary) to
larger urban farms (over one acre) within or on the periphery
of the city. In addition, the Austin City Council has encouraged
urban agriculture by authorizing relaxed zoning regulations for
private urban farms. For example, the current land code allows
for urban farming in all zoning classes, and, at this time, there
are 23 urban farms in the city of Austin, classified either as
market farms if less than one acre and as urban farms if
more than one acre, and 52 community gardens [
29
]. Further-
more, in 2009, the Austin City council created the Sustainable
Urban Agriculture and Community Garden Program with the
expressed purpose of streamlining the process for establishing
community gardens and sustainable agriculture on city land,
further endorsing urban agriculture in the city.
Much of the land in the suburban DDZ is in Texas Blackland
Prairie Geographic Region and contains prime farmland soils
according to the classification by the National Resources Con-
servation Service (NRCS) (Figure 2). The soils in this region
are known for being deep and rich with organic material, mak-
ing them valuable for agricultural use [
33
]. With the quality of
the soils, good drainage, and flat surface, prime farmland also
serves as ideal land for development. Indeed, many new devel-
opments are going to occur in prime farmland as a result of the
citys priority to develop in the suburban DDZ and the substantial
amount of open space in that part of the city. As a matter of de-
bate, the question is how much of the land to develop and what
positive and negative impacts are expected to occur. However,
the City of Austin, through its Imagine Austin plan, has indicated
that preserving a portion of different classifications of open land
is important for making Austin a sustainable city. The function of
urban agriculture in this plan, thus, has significance in terms of
protecting and valuing the environmental, social, and economic
well-being of Austin. Most significantly for this study, though,
is the role of urban agriculture as a means to conserve prime
farmland and serve as green infrastructure in Austin.
1.4. Purpose of Study
Urban agriculture acts as a multifunctional landscape with a
variety of benefits including the ability to offset many facets of
environmental degradation including preventing excessive runoff
[
34
]. The increase of new development and predominance of
urban farms in east Austin, combined with the rise of green
infrastructure as a stormwater management focus in the city,
makes east Austin an ideal study area for evaluating the poten-
tial role of urban agriculture as a green infrastructure strategy.
While this is the narrow aim of this study, the true value of urban
agriculture as green infrastructure can only be better understood
by placing the results of this research into a wider systems frame-
work that encompasses the multiple environmental, economic,
and social benefits offered by urban farms.
43
Figure 2.
Prime Farmland Soils in Austin, Texas almost
exclusively exist in east Austin, where the City of Austin is
encouraging growth and development to occur as part of
the Suburban DDZ.
The Imagine Austin plan explicitly addresses the
adoption of green infrastructure as a targeted future
land use with urban agriculture as a component of the
green infrastructure network. Addressing this area of
land use planning will require tools that can locate suit-
able areas within the city where urban agriculture can
best act as green infrastructure. In this study, a process
was developed to create a spatially explicit method of
siting urban agriculture as a green infrastructure tool on
hydrologically sensitive areas (HSAs), or areas prone to
runoff, in east Austin. The method uses geospatial tech-
nology to spatially analyze open access datasets that
include land use, a digital elevation model, and prime
farmland soils. Through this method a spatial relation-
ship can be made between areas of high surface runoff
and where the priority placement of urban farms should
be sited as a useful component of green infrastructure.
Planners or geospatial analysts could use such informa-
tion, along with other significant factors and community
input, to aid decision makers in the placement of urban
agriculture. Creating a spatially explicit approach for
siting potential urban farms will support the integration
of urban agriculture as part of the sustainable land use
planning of Austin.
2. Data and Methods
2.1. Study Area
This study examines the sub-watersheds of Decker
Creek and Elm Creek in east Austin (Figure 1). These
two watersheds were chosen because they are smaller
watersheds that both exist completely within the sub-
urban DDZ and reside in either the Full Purpose Ju-
risdiction or ETJ of Austin, whereas other eastern wa-
tersheds do not fit within those parameters. In ad-
dition, the SH130 growth corridor cuts through both
watersheds as well as the FM 969 growth corridor.
The impact of growth in the region and the expected
loss of prime farmland and agricultural land use make
these two watersheds ideal areas to study. Decker
Creek watershed is 17 square miles and Decker Creek
runs 12 miles from the top of the watershed to the out-
let. Decker Creek watershed is less developed than
other watersheds in Austin containing more agricultural
land, but is projected to experience a rise in population
growth from 3,156 people