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• Board Meeting Date: 7/11/2007
• Description: ISF Section - Hat Creek Water Right Acquisition
• Board Meetings - Doc Type: Memo

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Accepting this senior water right will potentially expand the period of time the existing instream
flow water rights on Hat Creek and East Brush Creek will be fully satisfied, which in turn should
increase the quality of the instream habitats associated with these two creeks.

10. Other Water RiQhts in Proposed Reach

Hat Creek - Except for two springs decreed to the U.S. Forest Service, there are no known
absolute water rights that divert from Hat Creek. The Town of Eagle has a conditional water
right for the Hat Creek Feeder Canal, decreed in CA 1529 on May 31, 1972 for 27 cfs with an
appropriation date of October 6, 1966. The proposed point of diversion is downstream of the
headgate of the Hat Creek Ditch.

East Brush Creek - There are several water rights on East Brush Creek decreed for irrigation,
domestic, municipal and industrial uses. Water Commissioner Bill McEwen has informed staff
that to his knowledge, there are no active diversions in the reach of East Brush Creek from just
upstream of its confluence with Hat Creek to its confluence with Brush Creek. Staff also
attempted to locate diversion records for these water rights with no success.

11. Potentiallniurv to ExistinQ RiQhts

Hat Creek - The Hat Creek Ditch water right, decreed for irrigation purposes in 1916, is the only
ditch that actively diverted water from Hat Creek until early 1990's. The donated water right was
historically used to irrigate approximately 22 acres of land. Except for a small amount of ditch
seepage losses that might have returned to Hat Creek, the diverted water was fully consumptive
to Hat Creek, as irrigation return flows accrued to East Brush Creek. There are no other
absolute water rights that divert downstream of the headgate of the Ditch that could be injured if
the Board changes the Hat Creek Ditch right to instream flow use. The Hat Creek Feeder Canal
conditional water right owned by the Town of Eagle is senior to the Board's existing Hat Creek
ISF water right and would be entitled to protection from injury related to any change of the Hat
Creek Ditch (donated) water right.

East Brush Creek - According to the Water Commissioner, there are no active diversions on
East Brush Creek. The Town of Eagle has two conditional water right decrees on East Brush
Creek. These rights, East Brush Creek Confluence Ditch and Town of Eagle Brush Creek
Intake 1, were each decreed for 10 cfs with 1977 adjudication and appropriation dates. The use
of the Hat Creek Ditch consumptive use credit to supplement the East Brush Creek ISF right is
not expected to impact the Town's conditional water rights.

12. Green Mountain Historic User Pool

The Hat Creek Ditch water right is junior to the principal water right for the Shoshone Power
Plant. According to Mr. Williamsen's engineering report, the Hat Creek Ditch benefited to some
degree in some years from the Green Mountain Historic Users Pool (HUP) releases with respect
to the Shoshone call.

By changing the use to instream flow, the Hat Creek Ditch water right would lose the HUP
protection and could be diverted by a downstream junior HUP water right. However, since there
are no downstream diversions, the water will likely flow downstream, thus supplementing the
ISF water rights on Hat and East Brush Creeks.

13. Effect of Proposed Acquisition on Maximum Utilization of the Waters of the State

The Hat Creek Ditch water right historically was used to irrigate hay and pasture grass, and the
consumptive use was historically lost to the stream. The proposal to change and use the water

Flood Protection' Water Project Planning and Fmance . Stream and Lake Protection
Water Supply Protection. Conservation Planning