Data and Interpretive Tools
Consolidated Standard Operating Procedures (SOP) for Calculating Bioassessment Indices and other Tools for Evaluating Wadeable Stream in California
This document describes steps in calculating three different ecological indices used to quantity stream conditions in California based on biological and physical data. The instructions herein are provided as support for analysts requiring scores for the California Stream Condition Index (CSCI), Algal Stream Condition Index (ASCI), and the Index of Physical Integrity (IPI).
Additionally, these instructions will help analysts calculate landscape-scale measures of human activity, which are used to determine if stream quality as reference sites.
- Instructions for Calculating Bioassessment Indices and other Tools for Evaluating Wadeable Streams in California: The California Stream Condition Index (CSCI), Algal Stream Condition Index (ASCI), and the Index of Physical Integrity (IPI) December 2020
California Stream Condition Index
The California Stream Condition Index (CSCI) is a biological index used to score the condition of BMI communities in perennial wadeable rivers and streams. Developed in 2013 to include a broader reference data set and to ensure better statewide applicability than previous regional indices, the CSCI combines two unique types of index that have traditionally been used separately: an observed-to-expected (O/E) index and a multimetric index (MMI). The CSCI is the first index to provide a consistent statewide standard for interpreting bioassessment data and is the basis of the new statewide Biological Integrity Assessment Implementation Plan.
- Bioassessment Scores Map
- CSCI Fact Sheet (December 2015)
- CSCI Technical Memo (October 2015)
- CSCI: Interim Instructions for Calculating Scores Using GIS and R (Revision date: August 1, 2018)
- Technical basis for the bioassessment scoring tool, the California Stream Condition Index - presentation by Pete Ode of the California Department of Fish and Wildlife to the State Board (Jan 2013)
Physical Habitat Integrity (IPI)
- The Physical Habitat (PHAB) Index of Physical Integrity (IPI): Interim Instructions (October 2018)
- Physical Habitat Index Technicial Memo (August 2018)
Indices of Biological Integrity - Archived
For most assessment applications, the CSCI should be used instead of these IBIs. The documents provided below are for informational purposes only.
Prior to the CSCI, several regional indices of biological integrity (IBIs) were developed for different portions of the state. An IBI uses multiple metrics to describe the biological condition of a stream or river. Included metrics vary by biogeographical region and benchmark values are based on reference sites considered to be relatively undisturbed by human activity.
- North Coast
- South and Central Coasts
- Development and comparison of stream indices of biotic integrity using diatoms vs. non-diatom algae vs. a combination - Abstract on Google Scholar (July 2013)
- A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams - Environmental Management 35(4):493-504 (2005)
- Calculating the South and Central Coast IBI (May 2009)
- Boundary map for the South Coast IBI (kml file) (Coming soon)
- Central Valley
- Western Sierra
- Eastern Sierra
- Development of a Benthic Macroinvertebrate Index of Biological Integrity (IBI) for Stream Assessments in the Eastern Sierra Nevada of California - D.B. Herbst and E.L. Silldorff (December 2009)
- Preliminary Index of Biological Integrity (IBI) for Periphyton in the Eastern Sierra (draft technical report) (August 2008)
- Calculating the Eastern Sierra IBI - MS-Excel spreadsheet calculator