Explicit Riparian Design

Current forest riparian protection practices within California and Washington mandate continuous buffer zones of relatively uniform width along all fish-bearing streams and along the lower reaches of many headwater streams. The scientific basis for most of these rules is typically drawn from broad trends and average conditions that often do not reflect actual conditions and ecosystem functions at the site-scale. There is growing interest within the forestry sector toward (and substantial scientific support for) using more site-specific information in the design of riparian buffers that will lead to more ecological diversity and improved overall riparian function for aquatic communities (especially salmonids and other endangered species). However, accepted cost-effective methods for evaluating and designing more active riparian management practices are generally lacking, and thus the ability to obtain regulatory approvals for site-based planning is limited, and filled with uncertainty. The result is continued reliance on state-wide rules despite the recognition of unintended negative consequences from such practices. The Explicit Riparian Design (ERD) Method Project proposes to provide a standardized method by which ecologically and economically effective buffer zone management practices can be determined by specific reach- and watershed-scale site conditions. The ERD Method will establish methods for evaluation and forecasting likely responses in several key riparian ecosystem exchange functions (tree growth and wood debris supply, nutrient cycling, thermal regulation, sediment supply, etc.) given site-specific information about the existing stand conditions and growth potential. It will set desired resource objectives and provide guidance for the priorities among competing objectives. It will also facilitate dialog with key agency staff so that the methodology can be accepted as a functional equivalent to existing regulations (both states currently have rules allowing alternative planning processes that the ERD will be designed to support). Once the ERD is fully developed, landowners will have a vetted procedure for the design of site-specific riparian practices that can maintain, restore and/or enhance ecological functions (e.g. thermal regulation, habitat development, etc) while reducing risks that may harm these functions over time (e.g. catastrophic fire, windthrow, infestation, etc). This will allow landowners to more efficiently manage the timber resource value from their lands while improving overall watershed and riparian response for fish, wildlife and water quality objectives. The ERD will also establish functional controls that will provide agency staff with greater confidence that proposed riparian management actions will not ultimately impose harm to beneficial uses and other ecosystem functions. These benefits will provide the context that will support more ecologically-based riparian management practices that can be used by consultants, landowners and others interested in more effective forest stewardship.