WAP 2001-2002 PRRIP

• Description: Staff Notebook for Platte River Research Cooperative Agreement ‎(aka Platte River Recovery Implementation Program or PRRIP)‎ Water Advisory Committee ‎(WAC)‎ Meetings including memos, comments, emails, minutes, letters, agendas, notes, etc. 2001-2002
• State: CO
• State: NE
• State: WY
• Basin: South Platte
• Water Division: 1
• Date: 1/1/2001
• Author: CWCB Staff
• Title: Staff Notebook for Platte River Research Cooperative Agreement Water Advisory Committee ‎(WAC)‎ Meetings for 2001-2002
• Water Supply Pro - Doc Type: Meeting

U-1
Peak Flows
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In the context of the Program, "peak flows" refer to the highest flows ma' fined for five
consecutive days in any given year. USFWS peak flow recommendations were presented in
Bowman and Carlson, 1994 (see Attachments B and Q. These are summarized as follows:
PEAK FLOWS
Exceedance probability
Recommended flow in cfs
Notes
(recurrence interval)
However, the Service recommends that efforts be made to protect the frequency and mamitude S�
of these naturally - occurring peak flows as new water - related activities occur in the Platte River
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basin. Because the Program is likely to augment the annual peak flow in many lower -flow years,
20% (l. in 5 years)
16,000 (Feb -Jun)
• 5 -day duration
existing conditions.
• At least 50% of these flows should occur/
Program Target Flows
between May 20 to June 20
• May -June preferred for habitat benefits
• Feb -June OK for channel maintenance
40% (2 in 5 years')
12,000 (Feb -Jun)
• 5 -day duration
10 -year running average
8,300 to 10,800 (Feb -Jun)
of 5- consecutive -day exceedance
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As described by Bowman and Carlson, the recommended peaks in excess of 12,000 cfs "will be
natural occurrences beyond the control of water resources managers in the Platte River basin ".
The Program is not will not create nor intentionally augment flows of this magnitude.
However, the Service recommends that efforts be made to protect the frequency and mamitude S�
of these naturally - occurring peak flows as new water - related activities occur in the Platte River
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basin. Because the Program is likely to augment the annual peak flow in many lower -flow years,
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it is anticipated that the Program will improve the 10 -year running average peak flow relative to`p�"
existing conditions.
Program Target Flows
`
Defined as the "species flow" plus the "annual pulse flow" recommendations, as described
above. The Program target flows are the flow levels that the Program actively seeks to establish
through provision of Program water and re- timing of river flows. Program target flows are used
as the basis for "scoring" the water - related benefits of Program activities relative to the 130,000 -
150,000 acre - foot /year First - Increment goal for reductions in shortages to targets (see discussion
in Section 3).1
1 "Scoring" refers to quantifying (in thousands of acre -feet) the extent to which a water - related activity
results (or is anticipated to result) in reductions in stream flow shortages to USFWS recommended flows, as
compared to the present condition. Scoring provides one tool for evaluating and comparing the potential benefits of
water - related activities in the context of the Program, however it is not the only means of assessing potential benefits
and adverse impacts.
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