Mission | Habitat
Conservation | Watershed Health
| Recreational Open Space
The mission of the Green Visions Plan for 21st Century Southern
California is to provide a guide to habitat conservation,
watershed health and recreational open space for the Los Angeles
metropolitan region, and to design planning and decision-support
tools to nurture a living green matrix for southern California.
Our goals are to protect and restore natural areas, restore
natural hydrological function, promote equitable access to
open space, and maximize support via multiple-use facilities.
The Plan is a joint venture between the University of Southern
California and the region's land conservancies, including
the Rivers and Mountains Conservancy, Santa Monica Mountains
Conservancy, Coastal Conservancy, and Baldwin Hills Conservancy.
The project area is depicted below and can be downloaded as
a GIS coverage.
The primary value of the Green Visions Plan has been to develop the tools necessry for needs-based, long-range plans.
The tools highlight the opportunities and constraints
that may arise as habitat conservation and restoration projects,
open space acquisitions and recreation improvements, and efforts
to protect watersheds are proposed and implemented. The tools
and data developed as part of the Plan also expand the
analytic and planning capabilities of local agencies and organizations
that seek to attract public funding or allocate their own
resources, reduce the fragmented, piecemeal approach to regional
resource planning, and promote projects whose collective impacts
— because they are part of a larger scientifically grounded
vision — are greater than the sum of their parts.
This vision and analytical approach is articulated in a white
Frameworks for the Green Visions Plan, which was informed
by a scientific workshop (report
here). Further description of this mission is also found
in the report Conservation
of Native Biodiversity in the City.
The long-term goals of the Green Visions Plan are to:
• Protect and restore natural areas to ensure the persistence
of native biodiversity and reintroduction of historically
present natural communities;
• Restore natural function to the hydrological cycle
to maximize groundwater recharge, improve storm water quality,
and minimize flood hazards;
• Increase and ensure equitable access for residents
to a range of open space types and recreational opportunities,
and thereby reduce socioeconomic and geographic disparities
in present-day patterns of access to these types of resources;
• Maximize political and financial support for the Plan
by proposing multiple-use facilities wherever possible to
meet the goals of habitat restoration and conservation, restoration
of hydroecological function, and provision of recreational
The mechanism to deliver information to achieve these goals
is a set of online planning tools that are available to anyone
with an interest in the region — agencies, advocates,
regulators, and the general public. These tools are presented
as an online mapping interface that depicts the results of
dynamic and static analyses for each parcel in the study area.
An introductory tutorial for the tools is available.
The habitat conservation analyses form the backbone of the
Green Visions Plan. These analyses include a detailed focal species assessment,
associated life history accounts and habitat suitability models;
historical vegetation map development; and species connectivity modeling.
Focal Species Assessment, Accounts,
and Suitability Modeling
A set of 30-40 focus species were identified as the basis
for the design of a corridor/reserve system for the Green
Visions Plan area (see Terrestrial
Target Species for Habitat Conservation Planning). This
report contains life history summaries and a rationale for
the use of each species as a target species. Then predictive
habitat maps were created for each of the 40 terrestrial species
and for an additional 6 aquatic species by the Conservation
Biology Institute (see Target
Species Habitat Mapping). These predictive maps have been
loaded on the online
tools. An additional online tool has been developed to predict whether restoration of any user-defined area will provide potential habitat for any of the target species. The predictive maps
can also be overlaid with a map of protected lands for the study
area to identify gaps in species protection.
Land Supply Inventory
Fundamental to all parts of the Green Vision Plan is an assessment
of current land supply by parcel, in the Plan area. Based
on existing land use and county tax assessor data, as well
as other sources, this inventory will include all vacant publicly
owned property and is provided as a coverage in the online planning tools
Design and Integrity Analysis
Connectivity between larger preserved areas and with smaller urban reserves is important to conserving biodiversity in urban landscapes. A subset
of five species representing different habitat types was selected
to investigate the need for corridors to connect isolated
fragments of habitat in the urban area. This approach quantifies the contribution of each natural area in the lanscape to connectivity of these species so that these values can be weighed in acquisition and planning.
Historic Vegetation Mapping
One of the features of the Green Visions Plan area is that
much of it has been urbanized, with many historic habitat
types being extirpated in the process. Yet central to goals
of the Plan is the restoration of historically present vegetation
communities, to achieve full representation of these landscape
types in the region. This raises the question of °restored
to what?°. To answer this question, historic vegetation
maps will be created on the basis of a variety of historic
sources, and then ground truthed. Suitability for supporting
one or more historically present vegetation communities will
be included on parcel scorecards.
Historic vegetation for the San Gabriel River was described in a joint project with the Southern California Coastal Water Research Project, CSUN, and the USC Center for Sustainable Cities. The report for this project can be downloaded here (appendices). The coverage of historic wetland types has been added to the planning tools.
Urbanized sections of the Plan area could become more hospitable
to wildlife if scattered habitat patches are located throughout
the region, allowing mobile species refuge and opportunities
for out-breeding. An assessment of the ability of such patches
to allow species to 'percolate' through the urbanized landscape
will be conducted, in order to guide plans for nature park
development, and score parcels accordingly.
Many municipal policies make cities more or less 'friendly'
to wildlife. Examples include night lighting; municipal pest
control procedures; public landscape practices; road, sidewalk
and median design; and companion animal control and shelter
policies. This task will provide a review of innovative 'wildlife
friendly' local government policies and practices from across
the country and beyond, and offer a set of model 'conservation
community' ordinances for local governments. We have completed
one report reviewing ordinances to minimize conflict between
humans and wildlife, "Nuisance"
A carefully crafted set of GIS tools, designed for specific
user groups (e.g., conservancies, local governments, community
groups) and providing for differential access to parcel-level
data, has been developed. These tools will enable users to
collect pertinent information about any parcel of interest, including the number of target species, what species would be supported if vegetation were restored, basic parcel characteristics
(such as size, zoning, and public/private ownership), and
the parcel's context with respect to surrounding
areas and their habitat, watershed, and recreational open
space features (e.g., distance to or wetlands, transportation infrastructure, etc).
This portion of the Green Visions Plan will provide an assessment
of a characterization of the region's watersheds and their
hydrodynamics, a picture of regional watershed assets, understanding
of water infrastructure that influences hydrological functioning
and potential for restoration, and an analysis of remediation
of source control possibilities. These analyses, and associated
data, are available at the parcel level.
Results and data layers are also key inputs to the habitat
conservation and recreational open space components of the
Green Visions Plan.
The Plan area contains a large number of watersheds and sub-watersheds
that form the most fundamental part of the region's green
matrix. We undertook a GIS analysis of watersheds within the Plan area, and
their features, including slope, elevation, vegetative cover,
soil type, and permeability. Both wildland and urbanized areas
of watersheds were characterized.
The characterization study identified regional
watershed assets that should be considered as part of reserve/corridor
Wastewater Infrastructure Assessment
In urban areas, natural hydrological systems have been radically
altered, through the diversion of streams to underground pipes
or channels, and the systems of storm drains to handle runoff.
This task will involve a characterization of the location
and capacity of this 'pipes and drains' infrastructure, in
order to assess the flows of surface runoff in the urban portions
of the Green Visions Plan area, and the water quality of that
runoff. It will also identify possible locations for stream
daylighting efforts. The products of this task will primarily
be intermediate inputs to other watershed health analyses.
One of the objectives of the Plan is to enhance the region's
ability to recharge ground water and restore parts of the
region's natural hydroecological character. Basic hydrological
models were used to estimate discharges to streams and
rivers, and the quality of these flows were assessed on
the basis of land use information. These reports were divided into five watershed areas: Santa Monica Bay, San Gabriel River, Calleguas Creek, Los Angeles River, and Santa Clara River.
Stream Channel Characterization and
Potential restoration of streams in the region – including
restoration of native habitat – depends on existing
channelization and diversion patterns. Also critical, however,
are alteration of stream flow regimes and geomorphology in
order to mimic historic patterns, via increasing upstream
permeability both to reduce flood risk in restored streams
and to 'dry' the landscape to reflect prior, more ephemeral
stream conditions. This task will characterize existing stream
channels in terms of annual and seasonal flows, sediment transport,
channel capacity, and bank characteristics in order to identify
candidate restoration sites.
Remediation and Source Controls
Some of the goals of protecting and restoring hydrecological
functioning in the Green Vision Plan area will require remediation
of runoff, and upstream source controls. The former may include,
for example, biological treatment facilities at stormwater
parks, so that incoming polluted flows can be treated before
entering the aquifer. The latter will involve the identification
of land use areas that require additional discharge controls
or treatments (such as high-tech street cleaners or on-site
runoff treatment facilities at industrial sites) and/or alterations
in permeability coefficients through removal of concrete/asphalt.
Three reports address this task: Stormwater Quality Control through the Retrofit of Industrial Surfaces, Best Management Practices for the Treatment of Stormwater Runoff, and Neighborhood Stormwater Quality Modelling.
The analysis of recreational open space for the Green Visions
Plan involves both an assessment of recreational open space
needs, and an analysis of current supply and multi-use opportunities
derived from habitat conservation and watershed health strategies.
Current Open Space Resources and
We characterized the quantity, quality and mix
of existing recreational open space opportunities, and their
geographic distribution. We developed a specialized assessment tool (Systematic Audit of Green-Space Environments) and used it to evaluate parks and park quality across the region.
Geographical and Fiscal Equity
Open space investments should be based in part on the need
to reduce the dramatic inequities in access to recreational
open space in the Plan area. Patterns of need will be compared
to the distribution of current resources and past spending,
to identify shortfalls in easy access (1/4 mile) to a mix
of recreational open space opportunities. We developed an online tool to describe the extent to which the
development of a particular parcel as recreational open space
would reduce inequity and described existing patterns of inequity in a comprehensive report.
Recreational Open Space Needs
The needs assessment will utilize 2000 Census data to characterize
the social geography of the Plan area (i.e., density, race/ethnicity,
socioeconomic status), and estimate the distribution of key
user subgroups (e.g., children/youth, elderly). The analysis provides tools to visualize the geographic distribution of recreational needs through the online tools.
Single and Multi-Use Opportunities
The online mapping tools allow for simultaneous visualization and analysis of recreational needs (as shown by park acres per person maps) with other environmental attributes, such as stormwater pollution or native species density. This integration of information can be incorporated by conservancies in planning focus areas for grant programs or by applicants to describe and quantify the multiple-benefit aspects of their projects.