R2Cross: Tool for Making Instream Flow Recommendations

Sponsor: Colorado Water Conservation Board

Duration: 2018–2019

PI: Ryan Morrison

Postdoc: Panagiotis Oikonomou

In 1973, the Colorado State Legislature vested the Colorado Water Conservation Board (CWCB) with the authority to appropriate instream flow water rights. Standardized field and office procedures help ensure that instream flow recommendations reflect the amount of water required to “preserve the natural environment to a reasonable degree,” as prescribed by state statute. R2Cross is one of the standard techniques used to model instream hydraulic parameters based on cross-sectional data collected in riffle habitat types. R2Cross has been used for a majority of the CWCB ISF appropriations over the last 45 years.

The latest upgrade to the R2Cross Program occurred 20 years ago to convert the model to a Microsoft Excel based program. This project updated the R2Cross Program to a web platform housed at the One Water Solutions Institute at CSU.

The updated R2Cross program can be found here: r2cross.erams.com

Ryan Morrison
Assistant Professor