Colorado River Basin Natural Flow and Salt Data

This information has been updated; please see the Colorado River Current Natural Flow and Salt Data page for the most recent data.

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. Presently the consumptive uses and losses data from 2006-2012 used to compute natural flow are PROVISIONAL and will be revised in the future. These revisions will change the natural flow computation.

Natural Flow and Salt Data Index

Current Natural Flow and Salt Data
      Documentation
      Natural Flow Supporting Data
      Natural Salt Supporting Data

Previous Natural Flow and Salt Data
1906-2012

PREVIOUS natural flow data 1906-2012 (Excel file, 1.6 MB) - Updated 1/8/15
Upper Basin: CSU extensions and MHYDRO 1906-1970 combined with recompiled JPrairie 1971-2012
Lower Basin: CSU extensions and March 1992 Reclamation report 1906-1970 combined with recompiled RButler 1971-2012

PREVIOUS natural flow data 1906-2010 (Excel file, 1.6 MB) - Updated 4/2/13
Upper Basin: CSU extensions and MHYDRO 1906-1970 combined with recompiled JPrairie 1971-2010
Lower Basin: CSU extensions and March 1992 Reclamation report 1906-1970 combined with recompiled RButler 1971-2010

PREVIOUS natural flow data 1906-2008 (Excel file, 1.3 MB) - Updated 1/26/11
Upper Basin: CSU extensions and MHYDRO 1906-1970 combined with recompiled JPrairie 1971-2008
Lower Basin: CSU extensions and March 1992 Reclamation report 1906-1970 combined with recompiled RCallejo 1971-2008

PREVIOUS natural flow data 1906-2007 (Excel file, 2.8 MB) - Updated 9/16/09
Upper Basin: CSU extensions and MHYDRO 1906-1970 combined with recompiled JPrairie 1971-2007
Lower Basin: CSU extensions and March 1992 Reclamation report 1906-1970 combined with recompiled RCallejo 1971-2007

PREVIOUS natural flow data 1906-2006 (Excel file, 2.8 MB) - Updated 6/16/08
Upper Basin: CSU extensions and MHYDRO 1906-1970 combined with recompiled JPrairie 1971-2005
Lower Basin: CSU extensions and March 1992 Reclamation report 1906-1970 combined with recompiled RCallejo 1971-2005

1971-2005 flow data revisions (PDF file, 12 KB) resulting from changes identified during update through 2006
1971-2004 flow data revisions (PDF file, 12 KB) resulting from changes identified during update through 2005
1971-2003 flow data revisions (PDF file, 12 KB) resulting from changes identified during update through 2004


1906-2005

PREVIOUS natural flow data 1906-2005 (Excel file, 2.7 MB) - Updated 6/22/07
(NOTE: **Data Used for Shortage FEIS and Triennial Review**)
Upper Basin: CSU extensions and MHYDRO 1906-1970 combined with recompiled JPrairie 1971-2005
Lower Basin: CSU extensions and March 1992 Reclamation report 1906-1970 combined with recompiled RCallejo 1971-2005


PREVIOUS natural salt mass data 1906-2005 (Excel file, 2.2 MB) - Updated 8/8/07
(NOTE: **Data Used for Triennial Review 2008**)
Upper Basin: Direct from regression based on 1971-2005 data
Lower Basin: 1906-1970 direct from regression based on 1971-2005 data combined with recompiled RCallejo 1971-2005


PREVIOUS natural salt concentration data 1906-2005 (Excel file, 1.5 MB) - Updated 8/8/07
(NOTE: **Data Used for Triennial Review 2008**)
Upper Basin: Direct from regression based on 1971-2005 data
Lower Basin: 1906-1970 direct from regression based on 1971-2005 data combined with recompiled RCallejo 1971-2005


Shortage FEIS natural salt mass data 1906-2005 (Excel file, 2.2 MB) - Updated 6/22/07
(NOTE: **Data Used for Shortage FEIS**)
Upper Basin: Direct from regression based on 1971-1995 data
Lower Basin: 1906-1970 direct from regression based on 1971-2005 data combined with recompiled RCallejo 1971-2005


Shortage FEIS natural salt concentration data 1906-2005 (Excel file, 1.5 MB) - Updated 6/22/07
(NOTE: **Data Used for Shortage FEIS**)
Upper Basin: Direct from regression based on 1971-1995 data
Lower Basin: 1906-1970 direct from regression based on 1971-2005 data combined with recompiled RCallejo 1971-2005


1906-2004

PREVIOUS naturalflow data 1906-2004 (Excel, 2.7 MB) - Updated 10/13/06
Upper Basin: MHYDRO 1906-1970 combined with recompiled JPrairie 1971-2004
Lower Basin: March 1992 Reclamation report 1906-1970 combined with recompiled RCallejo 1971-2004

PREVIOUS natural salt mass data 1906-2004 (Excel, 2.1 MB) - Updated 10/13/06
Upper Basin: Direct from regression based on 1971-1995 data
Lower Basin: 1906-1970 direct from regression based on 1971-2004 data combined with recompiled RCallejo 1971-2004

PREVIOUS natural salt concentration data 1906-2004 (Excel, 1.5 MB) - Updated 10/13/06
Upper Basin: Direct from regression based on 1971-1995 data
Lower Basin: 1906-1970 direct from regression based on 1971-2004 data combined with recompiled RCallejo 1971-2004


1906-2003

PREVIOUS natural flow data 1906-2003 (Excel, 2.7 MB) - Updated 9/23/05
Upper Basin: MHYDRO 1906-1970 combined with recompiled JPrairie 1971-2003
Lower Basin: March 1992 Reclamation report 1906-1970 combined with recompiled RCallejo 1971-2003
1971-1995 corrections (PDF, 15 KB) resulting from problems identified during update through 2003.


1906-1995

PREVIOUS natural flow data CY1906-1995 (Excel, 2.1 MB) - Updated 9/7/04
Upper Basin: MHYDRO 1906-1970 combined with recompiled JPrairie 1971-1995
Lower Basin: MHYDRO 1906-1970 combined with recompiled RCallejo 1971-1995

PREVIOUS natural salt mass data CY1906-1995 (Excel, 1.9 MB) - Updated 9/7/04
Upper Basin: Direct from regression based on 1971-1995 data
Lower Basin: MHYDRO 1906-1970 combined with recompiled RCallejo 1971-1995

PREVIOUS natural salt concentration data CY1906-1995 (Excel, 1.4 MB) - Updated 9/7/04
Upper Basin: Direct from regression based on 1971-1995 data
Lower Basin: MHYDRO 1906-1970 combined with recompiled RCallejo 1971-1995
Contact: bcoowaterops@usbr.gov
Last Updated: 30NOV2016