Assessment of ecological functions and flood-related risk on floodplains along major rivers in the Puget Sound basin
Presentation Abstract
Floodplains are vital part of landscape around the Salish Sea. Their aquatic and terrestrial habitats support diverse and productive biological communities. They are a focus for agricultural and urban development in the region. Because the dual importance of floodplains, their protection and recovery must accommodate ecological and social values through, for example, “multiple-benefits” projects that improve ecological function while reducing flood-related risks to people. Floodplains along the 17 major rivers flowing into Puget Sound were assessed to identify areas of opportunity for multiple-objective floodplain projects as part of the “Floodplains by Design” project. The assessment integrated existing geospatial data to evaluate five main ecological functions and two components of flood-related risk. Most of functions and risks are evaluated in terms of classes of land cover and connectivity that likely represent gross differences in the level of function or risk across these floodplains rather than using a continuous scale. For example, the classes used in the assessment of flood storage are based whether the floodplain is connected to a river and whether it has medium or high levels of development. Likewise, most of the functions and risks are evaluated for 10 m x 10 m cells in geospatially-referenced grids that extend across the floodplains. Some functions and risks do not manifest at such small scales, so they are evaluated for larger spatial units of floodplains. This regional-scale assessment is intended to inform a range of floodplain recovery efforts. The assessment highlights areas across Puget Sound with flood-related risks but also the potential to support many of the ecological functions of floodplains. The Puget Sound Partnership is using this information to develop goals and indicators of floodplain recovery. The Floodplains by Design project is using the assessment in discussions with local, state, and federal floodplain managers about how to accelerate floodplain recovery. Floodplain managers can use the assessment to “level the playing field” of information across various floodplains values and, thus, give more thorough consideration of multiple objectives in planning. By emphasizing the integration of basic geospatial information into a category of function and risk rather than a value along one-dimension scale, the assessment products can serve a variety of audiences with distinct values and missions.
Session Title
Session S-06G: Integrating Landscape Scale Assessments Into Local Planning I
Conference Track
Planning Assessment & Communication
Conference Name
Salish Sea Ecosystem Conference (2014 : Seattle, Wash.)
Document Type
Event
Start Date
1-5-2014 1:30 PM
End Date
1-5-2014 3:00 PM
Location
Room 6E
Genre/Form
conference proceedings; presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Floodplains--Washington (State)--Puget Sound; Floodplain management--Environmental aspects--Washington (State)--Puget Sound; Floods--Risk assessment--Washington (State)--Puget Sound
Geographic Coverage
Salish Sea (B.C. and Wash.); Puget Sound (Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Assessment of ecological functions and flood-related risk on floodplains along major rivers in the Puget Sound basin
Room 6E
Floodplains are vital part of landscape around the Salish Sea. Their aquatic and terrestrial habitats support diverse and productive biological communities. They are a focus for agricultural and urban development in the region. Because the dual importance of floodplains, their protection and recovery must accommodate ecological and social values through, for example, “multiple-benefits” projects that improve ecological function while reducing flood-related risks to people. Floodplains along the 17 major rivers flowing into Puget Sound were assessed to identify areas of opportunity for multiple-objective floodplain projects as part of the “Floodplains by Design” project. The assessment integrated existing geospatial data to evaluate five main ecological functions and two components of flood-related risk. Most of functions and risks are evaluated in terms of classes of land cover and connectivity that likely represent gross differences in the level of function or risk across these floodplains rather than using a continuous scale. For example, the classes used in the assessment of flood storage are based whether the floodplain is connected to a river and whether it has medium or high levels of development. Likewise, most of the functions and risks are evaluated for 10 m x 10 m cells in geospatially-referenced grids that extend across the floodplains. Some functions and risks do not manifest at such small scales, so they are evaluated for larger spatial units of floodplains. This regional-scale assessment is intended to inform a range of floodplain recovery efforts. The assessment highlights areas across Puget Sound with flood-related risks but also the potential to support many of the ecological functions of floodplains. The Puget Sound Partnership is using this information to develop goals and indicators of floodplain recovery. The Floodplains by Design project is using the assessment in discussions with local, state, and federal floodplain managers about how to accelerate floodplain recovery. Floodplain managers can use the assessment to “level the playing field” of information across various floodplains values and, thus, give more thorough consideration of multiple objectives in planning. By emphasizing the integration of basic geospatial information into a category of function and risk rather than a value along one-dimension scale, the assessment products can serve a variety of audiences with distinct values and missions.
