Colorado River Basin Natural Flow and Salt Data
This documentation supports the Current Natural Flow and Salt Data for the Colorado River found on this web site.
NOTE: Several of these files are extremely large, and are best accessed by downloading before reading. To do so, "right click" on the link and select "Save Target As" to save the file to your hard drive.
Natural Flow and Salt Data IndexCurrent Natural Flow and Salt Data
Natural Flow Supporting Data
Natural Salt Supporting Data
Previous Natural Flow and Salt Data
Natural Flow and Salt Computation Methods (PDF,
780 KB) - presented at the Colorado River Forecasting Service meeting on November 22, 2005.
Natural Flow and Salt Computation Methods Technical Report (PDF, 4.2 MB)
Additional figures that are not provided in above documentation. Comparisons of 1971-1995 Recomputed Natural Flow and Salt with MHYDRO 1971-1990:
- Upper Basin Intervening Natural Salt Mass (Excel, 2.1 MB)
- Upper Basin Total Natural Flow (Excel, 2.3 MB)
- Upper Basin Total Natural Salt Mass (Excel, 3.2 MB)
- Lower Basin Intervening Natural Flow and Salt Mass (Excel, 3 MB)
- Lower Basin Total Natural Flow and Salt Mass (Excel, 3 MB)
CO Natural Flow Report (PDF, 4 MB) - Jeff Rieker, U.S. Department of the Interior, Bureau of Reclamation - Denver Office. Includes data analysis of the natural flow data last updated 9/7/04 from 1906-1995.
Record Extension of Monthly Flows for the Colorado River System, (PDF, 2 MB) T. Lee and J. Salas, Dept. of Civil Engr., Colorado State University, December 2006.
DRAFT Colorado River Simulation System Hydrology Data Base (PDF, 10 MB), U.S. Department of Interior, Bureau of Reclamation, Upper Colorado Region, June 1983.
Colorado River Simulation System, Hydrology Data Base Lower Colorado Region (Lees Ferry to
Imperial Dam) (PDF, 7.4 MB), U.S. Department of Interior, Bureau of Reclamation, Lower Colorado Region, May 1985.
Colorado River Simulation System, Hydrologic Flow and Salt Data Base for the Lower Colorado
Region, Lees Ferry to Imperial Dam (PDF, 8.4 MB), U.S. Department of Interior, Bureau of Reclamation, March 1992.
Upper Basin Consumptive Uses and Losses
Consumptive uses and losses reports (1971-2017) are available on Reclamation's Upper Colorado Region website.
Supporting data for consumptive uses and losses computation
Consumptive Uses and Losses spreadsheet 1971-2016 (Excel, 12.6 MB). The spreadsheet provides most all of the source data required to compute consumptive uses and losses data at a monthly eight digit HUC level. The irrigated agriculture data in the spreadsheet from 1971-1980 are supported in separate files available upon request.
NOTE: In order for embedded macros to work, macro security in Excel must be set at "medium" or "low". This security can be changed in Excel by clicking Tools, Macro, Security, and selecting either "medium" or "low".
Last Updated: 01APR2019