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about the green visions plan

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 paper Analytical 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; and
• 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 open space.

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.


Habitat Conservation (top)

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

Bioreserve 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.

Species Percolation
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.

Model Ordinances
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" Urban Wildlife.

GIS Tools
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).

Watershed Health (top)

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.

Watershed Characterization
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 system design.

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.

Hydrological Modeling
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 Restoration Assessment
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.

Recreational Open Space (top)

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 Investment Patterns
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 Evaluation
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 Assessment
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.


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