Milhous, Robert T., authorColorado State University, publisher2020-02-202020-02-202017https://hdl.handle.net/10217/201091http://dx.doi.org/10.25675/10217/2010912017 annual AGU hydrology days was held at Colorado State University on March 20 - March 22, 2017.Includes bibliographical references.At the beginning of the decade of the 1970's it was clear that unless an instream flow regimens was quantified the need for an instream flow. Three 1970's methods are reviewed: 1) a method based on the characteristics of the streamflows is the Montana Method, 2) a method based on the hydraulic attributes of the channel is the Water Surface Profile Method, and a method that uses hydraulic attributes contained in papers on the Montana Method. Strong points of the Montana Method are the relation between the magnitude of the instream flow and the quality of the habitat, and the variation of the instream flow between seasons. The WSP Method did link biological needs to river hydraulics which is a strong point. These links have proven to be very fruitful in instream flow studies. The Montana Method hydraulic criteria are useful but there is a stream size effect that was not accounted for in the application of the criteria.born digitalproceedings (reports)engCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.Text