BOARD00820

• Board Meeting Date: 7/26/2006
• Description: ISF Section - Pine River Proposed Water Donation - La Plata County
• Board Meetings - Doc Type: Memo

According to data provided by PRID and the Tribe, there were only
2 years of significant insufficient irrigation supply (1977 and 2002)
during Ihe period of record, and two other years when late .
irrigation demands could not be mel. In addition, there were 7
years out of 45 years of record (15%) where Vallecito Reservoir
did not fill to a level of 110,000 acre-feet.

U.S. Bureau of Reclamalion records of Vallecito Reservoir
releases reflect post-drought reservoir operations.
htto://www.usbr.cov/uclwcao/water/rsvrs/dslvallecito.html

Valleelto Reservoir - Average Monthly Releases (efs)

OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEPT
2002 303 50 50 46 25 25 48 532 524 70 107 86
2003 62 10 6 6 6 6 6 373 675 593 430 104
2004 69 6 6 6 6 6 113 692 823 676 614 541
2005" 413 224 165 17 486 547 558 1290 947 742 623 528
2006' 87 66 13 31 667

. provisional data

According to information provided by PRID and the Tribe, during
the dry year condition (60K storage), releases of 50 cfs might be
expected approximately 60% of Ihe time, and releases of 25 cfs or
less might be expected approximately 40% of the time. Except for
certain emergency conditions described in Ihe agreement,
releases would never be less Ihan 5 cfs.

Other Water RiQhts in Proposed Reach:

There are numerous water rights in the proposed instream flow
reach, the majority of which are decreed for irrigation. In addition,
there are many undecreed uses and exchanges of water being
made for stock water, irrigation, augmentation and other uses.
PRID, the Tribe and the State and Division Engineers are currently
working with water users to adjudicate these uses.

.

Potentlallnlurv to Existlna RIQhts:

The water to be used for instream flows will be stored in Vallecito
Reservoir under a junior priority water right. Water released from
storage for inslream flow use pursuant to Ihe donalion agreement
will not be subject to the priority system. As a result there should
be no injury to exisling water rights.

Effect of the proposed aCQuisition on the maximum utilization of the waters of the state?
Will the aCQuired water be available for subseQuent use downstream?

The amount of water donated to the Board for instream flow use
may also be water which is delivered to downstream contract
water users, Ihereby facilitating maximum utilizalion of the waters
of the state.

Effect of the proposed aCQuisition on anv relevant interstate compact issue?

Based on the information currently available, the proposed
acquisition does not appear 10 affect any interstate compact issue.

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