This is the information and download page for inSTREAM 7 and inSALMO 7, the current versions as of September, 2021.

Training materials--presentations on various steps in applying and using the models from the inSTREAM/inSALMO training class in August, 2022--are now available below. Please contact us if you are interested in training.

Key differences from previous versions of inSTREAM and inSALMO are:

  • Simulation of the full daily light cycle (dawn, day, dusk, night) and how trout behavior and habitat use depend on light.
  • Completely new software in the NetLogo platform, making inSTREAM 7 much easier to install, use, and customize.
  • A thorough update of all model assumptions and parameter values.
  • An extensive new user manual that describes the model, its software, and its application to new sites.

The InSTREAM 7 User Manual is now available as an official US Forest Service report, from this site: We recommend this report as a citation for the complete model description. However, the most up-to-date (but unofficial) versions of the User Manual are available below on this page.

This publication summarizes what's new in inSTREAM 7 and how its use differs from traditional instream flow assessment, and provides a brief example application. This publication describes the method we introduce for modeling habitat and activity (feeding vs. hiding) selection behavior through the daily light cycle and demonstrates its capabilities. This publication illustrates how inSTREAM 7's predictions of trout population responses to flow and temperature can differ from those of models that neglect the daily light cycle.

The most current releases are inSTREAM/inSALMO 7.3, updated 11 January 2022 (file names with "2022-01-11"). 

All versions of inSTREAM and inSALMO 7 prior to those dated 11 October 2021 had a code error that appears to cause relatively small effects on population results, except when many fish use the "search" feeding mode. The error was found by Dr. Uwe Grueters and colleagues at Justus-Liebig-Universität Giessen, Germany, who completely re-programmed inSTREAM 7 in a different software platform and compared results to those of our NetLogo implementation. Our thanks to Dr. Grueters for sharing this very comprehensive code test with us.

Version 7.3 has only one difference from 7.2 in model formulation--how habitat and activity selection decisions depend on growth and size--but includes a number of minor software improvements. Version 7.3 also is better at extrapolating cell depths and velocities at flows between zero and the lowest provided in hydraulic input. Each code and documentation file includes a log of changes among releases.

We support inSTREAM 7 and inSALMO with limited free assistance, training, collaboration, or consulting; contact Steve Railsback for support.

The following table provides model software and documentation. Software is distributed as a ZIP archive of a directory containing the model's NetLogo file and example input files. Installing it requires only (a) installing NetLogo version 6.2 or later from here and (b) unzipping the inSTREAM or inSALMO distribution. The model can then be started by double-clicking on the NetLogo file, named something like InSTREAM***.nlogo.


VersionDescriptionSoftware and example inputDocumentationLast updated
InSTREAM 7.3The current public release of inSTREAM 7.File archive with code and input for two examples: (A) one trout species and one stream reach, (B) three species and three reaches (ZIP; 1.6 MB)Complete user manual (PDF, 7 MB), updated with each release.7 July 2023
InSTREAM 7.3-SDModification of inSTREAM 7.3 to represent sub-daily flow fluctuations such as from peaking hydropower.File archive with code and example input (ZIP, 1.5 MB)Documentation of differences from inSTREAM (PDF).7 July 2023
InSTREAM 7 test proceduresOptional NetLogo code file with procedures that produce test output files. Potentially useful for testing code modifications or debugging (ZIP archive containing a NetLogo code file, which is plain text)See notes at top of file.14 Sept 2021
InSALMO 7.3InSALMO salmon model: A modification of inSTREAM 7.3 to represent adult holding, spawning, redd incubation, and juvenile rearing and outmigration of anadromous salmon in addition to resident trout.File archive with code and example input representing three stream reaches, two salmon species, and one trout species. (ZIP, 1 MB)Documentation of differences in model and software from inSTREAM (PDF).7 July 2023
Output file filtererA utility program (in NetLogo) that filters large output files and keeps only lines with selected contents, such as specific dates, species, times of day.Zipped NetLogo code file: OutputFileFilterer.nlogoSee the "Info" tab in the NetLogo file.5 July 2023
Habitat report writerA NetLogo procedure that reports the area of user-defined "good" habitat for a specific species and size fish, over a selected time period. Useful for understanding the importance of physical habitat in InSTREAM/InSALMO results.Zipped auxiliary NetLogo code file InSTREAM7.3_HabitatReportWriter.nls (plain text format)See comments in the file.3 March 2024
Training materialsA zip file with 8 presentations (PDF format) on: model purposes and history, software introduction, model description, field methods, validation and credibility, simulation experiment design and analysis, calibration, and miscellaneous tools and add-ons. From our August 2022 training

We also maintain an archive of our extensive code tests, which are available upon request.