Riparian Conditions

The inclusion of Riparian Conditions to the SSHIAP system will allow for multi-scale assessment of riparian reserves in the State of Washington. Documentation of riparian conditions around the state will allow for the assessment of existing conditions relative to the three categories of function (“properly functioning”, “at risk”, and “not properly functioning”) presented in the National Marine Fisheries (NMFS) document entitled “Making Endangered Species Act Determinations of Effect for Individual or Grouped Actions at the Watershed Scale”. This 1996 document provides guidance for evaluating the effects of human activities in a consistent and accurate manner (Stelle 1996). Within this document the three categories of function relative to riparian reserves have been adopted from Winward (1989) and are written as follows:

• Properly Functioning - the riparian reserve system provides adequate shade, large woody debris recruitment, and habitat protection and connectivity in all subwatersheds, and buffers or includes known refugia for sensitive aquatic species (>80% intact), and/or for grazing impacts: percent similarity of riparian vegetation to the potential natural community/composition >50%.
• At Risk - moderate loss of connectivity or function (shade, LWD recruitment, etc.) of riparian reserve system, or incomplete protection of habitats and refugia for sensitive aquatic species (»70-80% intact), and/or for grazing impacts: percent similarity of riparian vegetation to the potential natural community/composition 25-50% or better.
• Not Properly Functioning - riparian reserve system is fragmented, poorly connected, or provides inadequate protection of habitats and refugia for sensitive aquatic species (<70% intact), and/or for grazing impacts: percent similarity of riparian vegetation to the potential natural community/composition <25%.

Modeled after the Washington State Watershed Analysis protocol (Washington Forest Practices Board 1995), both the SSHIAP and Watershed Analysis (WA) methods rely primarily on aerial photo interpretation to determine size (age), density, and species composition of riparian forests. The most significant departure from the WA method proposed by SSHIAP is the assessment of a wider area adjacent to stream channels. It is proposed that the riparian assessment area include a 240 ft band on either side of all channel/wetland/lake/slough segments. A justification for this buffer width is found in Pollock and Kennard (1998).

The SSHIAP team is currently developing methodology to allow for the quantification of riparian habitat. Approaches under consideration include Watershed Analysis methodology developed by the Washington Forest Practices Board and GIS driven analysis of satellite-derived data.

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