BOARD00368

• Board Meeting Date: 7/23/2001
• Description: WSP Section - South Platte Reconnaissance Study Update and Decision to Proceed with Feasibility Study
• Board Meetings - Doc Type: Memo

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The CA water goal is to increase flow in the Central Platte by 130,000 to150,000
annually. Colorado has committed to providing 27,000 acre-feet of water per year as our
contribution. Colorado believes that the best means of providing our portion of the water
is primarily through ground water re-regulation. This approach involves moving or
retiming river flows from periods when flows are in excess to South Platte Compact
(Compact) and endangered species needs to periods where there are flow shortages. The
plan is commonly referred to as the Tamarack Plan because it in part involves water
management at the Tamarack Ranch State Wildlife area,

CWCB staff believes that is prudent to evaluate how surface storage may help Colorado
"fine tune" our water management activities for the benefit of Colorado water users and
to facilitate our participation in the CA. The reconnaissance level Study helps clarify
specifically how this may be accomplished. However, it does not answer all the
significant question and logistics, and it is recommended that a feasibility level study be
implemented to further identify possible options and solutions.

As a final piece of background information the Board will recall that this project is on a
"fast track" and the Board approved (at the January 18,2001 meeting) up to $500,000.00
for completion of a feasibility study and design. The Board's approval requested that
staff obtain a formal recommendation from the Board prior to embarking on either a
feasibility study or design.

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The remainder of this memorandum will focus on the major findings the reconnaissance
level Study.

Reconnaissance Level Studv Summary

The purpose ofthe Study was to identify potential structural and non-structural water
management alternatives along the Lower South Platte River extending generally from
the Harmony Ditch No, 1 headgate near Crook, Colorado downstream to the State line.
The project would develop available water under a junior decree, Water thus developed
could be available for supplying a variety of beneficial uses, including:

· Providing an alternative and/or new source of augmentation.

· Improving water rights administration through increased flexibility for storing and
releasing augmentation water.

· Improving stream flows to improve habitat for Colorado minnow species of
concern and for other environmental purposes such as waterfowl and riparian
habitat.

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Each of the above uses have potential interrelationships with the water development
efforts for the CA. The current Study only focuses on the potential to develop and store
water. A feasibility level study would refine the specific uses and quantities of water that
could be allocated for various purposes, and any relationships that may exist with the CA
efforts,

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