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Open Access Publications from the University of California

Scholarly Works (3 results)

  • Article
Restoration of Rivers and Streams (LA 227) (2004)

Post-project evaluation and monitoring of stream restoration projects are rarely conducted, and long-term evaluations are even less common but are needed in order to gage the success of a project and to determine the time scale of biological recovery in the system. This study is a 5-year comparison to an initial post-project assessment completed in 1999 that evaluated an urban stream restoration project in Poinsett Park (El Cerrito, California). The results of this study found that habitat quality differed spatially between reaches, but was temporally similar in 1999 and 2004 with slight improvements at the restored reach in 2004. The biological assessment in 2004 found no improvements in ecological condition of the biotic assemblage compared to 1999. This lack of improvement may be attributed to the detrimental and limiting effects of a highly urbanized watershed. It is also possible that the aquatic communities successfully colonized the restored reach within the 2 years following the completion of the restoration project in 1997. A survey of the neighborhood residents indicated that, overall, they were pleased with the restored creek site 7 years after the completion of the project. Approximately half of the residents that moved to the neighborhood after the restoration project was completed were unaware that this segment of creek was previously underground. Long-term evaluations of restoration projects can help managers and designers of future projects determine the timeline of the success of a project.

  • 1 supplemental file
Cover page: A long-term post-project evaluation of an urban stream restoration project (Baxter Creek, El Cerrito, California)
  • Article
Hydrology (2004)

Stream alterations and human disturbances over time have reduced salmonid fish populations in Redwood Creek (Marin County, California). A restoration project in fall 2003 sought to increase the number of juvenile fish rearing pools along an 1800-foot reach of Redwood Creek. To evaluate the success of this project, we characterized changes in channel morphology through feature and facies mapping and photo-documentation in a 432-foot sub-reach of the restoration site. Our post-project evaluation found that the installation of large woody debris weir structures was successful in creating pools and increasing the overall habitat complexity of this sub-reach. Our detailed survey map provides a basis for future monitoring at the Redwood Creek restoration site or other sites in need of evaluation.

    Cover page: Post-restoration changes in bed material and channel features, Redwood Creek, Marin County
    • Article
    • Peer Reviewed
    UC Berkeley Previously Published Works (2009)
    Long-term variability of bioassessments has not been well evaluated. We analyzed a 20-year data set (1984–2003) from four sites in two northern California streams to examine the variability of bioassessment indices (two multivariate RIVPACS-type O/E scores and one multimetric index of biotic integrity, IBI), as well as eight metrics. All sites were sampled in spring; one site was also sampled in summer. Variability among years was high for most metrics (coefficients of variation, CVs ranging from 16% to 246% in spring) but lower for indices (CVs of 22–26% for the IBI and 21–32% for O/E scores in spring), which resulted in inconsistent assessments of biological condition. Variance components analysis showed that the time component explained variability in all metrics and indices, ranging from 5% to 35% of total variance explained. The site component was large (i.e., >40%) for some metrics (e.g., EPT richness), but nearly absent from others (e.g., Diptera richness). Seasonal analysis at one site showed that variability among seasons was small for some metrics or indices (e.g., Coleoptera richness), but large for others (e.g., EPT richness, O/E scores). Climatic variables did not show consistent trends across all metrics, although several were related to the El Niño Southern Oscillation Index at some sites. Bioassessments should incorporate temporal variability during index calibration or include climatic variability as predictive variables to improve accuracy and precision. In addition, these approaches may help managers anticipate alterations in reference streams caused by global climate change and high climatic variability.
      Cover page: Long-Term Variability in Bioassessments: A Twenty-Year Study from Two Northern California Streams
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