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ASLA-NCC

American Society of Landscape Architects
Northern California Chapter

Awards

2013 Awards

2013 Research, Planning, Analysis and Communication

Merit Award

Breuner Marsh Restoration and Public Access Project
Richmond, CA
Studio Renovo at WRA, WRA, Inc.
Lead Landscape Architect: George Salvaggio
Client: East Bay Regional Park District

Breuner Marsh Context Map–The Breuner Marsh Restoration and Public Access Project is a tidal marsh restoration and public trail project located on East Bay Regional Park District property off of San Pablo Bay in Richmond, California. The new park will be a valuable open space resource for the residents of neighboring Parchester Village as well as for regional visitors.
Plants and Animals of the Tidal Marsh–Tidal marshes support a variety of plants and animals, including endangered species such as California clapper rail, salt marsh harvest mouse, and salt marsh bird’s beak. Each zone of the tidal marsh provides specific conditions necessary for plant growth, as well as food, cover, and nesting habitat for wildlife.
Tidal Inundation and Correlation with Habitat–The diurnal (daily) tidal cycle influences the vegetation composition of the tidal marsh ecosystem. The vegetation of each tidal marsh zone corresponds to the frequency and depth of tidal inundation.
Design Elevations and Indicator Plants–We surveyed the elevation ranges for tidal marsh indicator plant species to understand the relationship between the frequency of tidal inundation and the elevation ranges of the tidal marsh zones.  We used this method to establish the design elevations (i.e., planting zones) for the marsh restoration.
Mapping Habitat by Elevation–We used the elevation ranges for each tidal marsh indicator plant to map the distribution and extent of the tidal marsh zones at current sea levels and under predicted future sea levels.
Topographic Analysis to Determine Cost Effective Excavation–One of the primary factors driving the marsh restoration design was the cost of excavation and grading. We performed a GIS analysis using topographic data to identify low cost areas for excavation. The analysis was done by transforming the topographic data to indication the depth of excavation required to create salt marsh and setting an excavation threshold based on cost.
Sea Level Rise Evaluation to Determine Soil Disposal Mound Locations–Low-lying upland areas are expected to convert to tidal marsh under rising sea levels, and these areas should be preserved during the design phase to allow for this shift in habitat type. We performed a GIS analysis to predict the distribution and extent of tidal marsh zones in the future to ensure that soil disposal mounds would not be located in upland areas expected to convert to tidal marsh under elevated sea levels.
Breuner Marsh Site Plan –In addition to providing habitat for endangered species, the restored Breuner Marsh will also include parking, a picnic area, a section of the Bay Trail, boardwalks, and viewpoints. Approximately 100,000 cubic yards of soil will be excavated to restore the tidal marsh, and disposal soils will be placed and shaped in the upland areas to accommodate ADA-accessible public trails and facilities at elevations high enough to protect them from rising sea levels.
Breuner Marsh Site Plan with 2-D Hill-Shade Graphics–Stakeholders and environmental regulators had difficulty using topographic contour data to visualize key project relationships.  To overcome this challenge, we used 2-D Hill-Shade Graphics to illustrate existing and proposed topography, providing clarity to people unfamiliar with reading grading plans and facilitating conflict resolution and consensus building among stakeholders and regulators.
Evaluating Restoration Alternatives in the Context of Sea Level Rise–The 2-D Hill-Shade graphics and habitat elevation analysis were also used to illustrate and quantify the distribution of each tidal marsh zone under current and future sea level scenarios.
Evaluating Elevation and Spatial Relationships in the Context of Sea Level Rise– Conceptual cross sections illustrate elevation relationships between the Bay Trail and the restored tidal marsh and wetlands under current and future sea level scenarios.
Protecting Public Facilities from Rising Sea Levels–We evaluated the project alternatives under current and future sea level scenarios.  We placed soil disposal mounds and shaped upland areas to accommodate ADA-accessible facilities, and these areas were designed to be high enough to protect them from rising sea levels.

The Breuner Marsh Restoration and Public Access Project aims to restore 30 acres of tidal marsh and seasonal wetlands in Richmond, California.  The project will protect habitat for the endangered California clapper rail and salt marsh harvest mouse and will provide an extension of the San Francisco Bay Trail, filling a key 5,960-foot gap near Point Pinole Regional Shoreline Park.  Multi-goal projects are challenging, often involving a balance among conflicting objectives.  These challenges become more complex with sea level rise predictions and other issues related to global climate change.  To tackle these challenges, we developed a tool kit to evaluate design alternatives in the context of sea level rise, including topographic and vegetation analyses, evaluation of restoration design in the context of sea level rise, and graphic communication with stakeholders.  The project provides an example of innovative uses of existing tools to solve complex problems in landscape architecture.