BOARD00088 ‎(2)‎

• Board Meeting Date: 11/14/2006
• Description: WSP Section and ISF Section - Arkansas River ISF Appropriation
• Board Meetings - Doc Type: Hearings

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The DOW has reviewed the data collected to date and believes a 100 cfs year-round in stream
flow would preserve the natural environment to a reasonable degree, as provided in the letter
(copy attached) to Ted Kowalski from Mark Uppendahl dated May 5, 2006. DOW recommends
that the CWCB appropriate the 100 cfs proposed in stream flow.

Hydrologic Data

After receiving DOW's biologic recommendation, the CWCB staff conducted an evaluation of
the stream hydrology to determine if water was physically available for an instream flow
appropriation. In determining water availability, CWCB Staff examined two of the historic
stream gages on the Arkansas River: (1) Arkansas River above Pueblo, Colorado (USGS Gage
07099400) and (2) Arkansas River at Moffat Street at Pueblo, CO (USGS Gage 07099970).
Table 2 displays the average and 50% exceedence monthly flows on the Arkansas River at the
Arkansas River above Pueblo gage. This gage is directly downstream from Pueblo Reservoir
and is located upstream of both proposed instream flows For the period of record of this gage
(1965 - 2004), both the monthly average and the 50% exceedence are greater than the
recommended 100 cfs flow amount. Table 3 displays the average and 50% exceedence monthly
flows on the Arkansas River at the Arkansas River at Moffat Street gage. This gage is located
between the two proposed instream flows and is affected by several diversions within the reach.
For the period of record of this gage (1988 - 2004), the monthly average and 50% exceedence
are greater than the 100 cfs recommendation for all months of the year with the exception of
December and January.

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