PUB00155

• Year: 2007
• Title: The Colorado River The Story of a Quest for Certainty on a Diminishing River
• CWCB Section: Administration
• Author: Eric Kuhn
• Description: The Colorado River The Story of a Quest for Certainty on a Diminishing River
• Publications - Doc Type: Other

Table VI-l Natural Flow Estimates

Study or Effort Time Natural Flow at Lee Ferry Natural Flow at Yuma
Period
1922 Compact Negotiations 1903-1992 17-18 maf 20-22 maf
(Yuma)
1928 Siebert Commission' 1878-1926 15.3 to 16.2 maf 18-20 maf
(Yuma)
lID 419 (1947) USBR 1897-1943 16.27 maf 17.72 mat'
UCRC Engineering 1914-1945 15.64 mat" N/A
Committee 11/29/48
Tipton & Kalmbach for 1896-1965 14.9 maf5 N/A
UCRC, July 1995
USBR CAP Senate Hearings 1914-1958 15.07 ma:F 16.03 maf
1967
UCRC 2004 Annual Report 1896-2004 14.8 mafl N/A
USBR Natural Flow Data 1906-2000 15.28 mal: N/A
Base
USBR Natural Flow Data 1931-1977 13.59 maro N/A
Base
Kanzer & Kuhn 1906-1990 N/A 17.32 mar'

TABLE FOOTNOTES

IThe Siebert Commission Report did not actually present any numbers, but it concluded that previous estimates were too high by 10%.

2House Document 419, Table CXL, page 281.

3id., page 284.

4Engineering Advisory Committee, Final Report, November 29, 1948, page 62.

5I've shown an unlabeled graph from the 1965 report as Figure VI-I.

6Hearings before the Subcommittee on Water and Power Resources, Ninetieth Congress, First Session on S1004, S 1013, S1242, and
S1409, May 2-5. 1967, page 208.

7id., page 208. It is not clear from the testimony or chart whether this includes the Gila I suspect it does not.

8Fifty-Sixth Annual Report of the Upper Colorado River Compact Commission, September 30,2004, Table 3.

91 used the same USBR Lee Ferry natural flow estimates that were used for the pending review of the Hydrologic Determination. The
USBR natural flow data base is slightly different than the UCRC, especially for the 1950s.

Wid.

IIThis estimate is based on a correlation between the Little Colorado River natural flows from the Reclamation natural flow data base
and the Gila River natural flows from HD 419 to determine natural Gila flows at Yuma The Gila flows at Yuma are added to the
Colorado River natural flows at Imperial Dam from the Reclamation natural flow data base.

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