BOARD00910

• Board Meeting Date: 7/13/1998
• Description: CF Section - Feasibility Studies - Ryan Gulch Reservoir Co. - Request for Feasibility Study Grant
• Board Meetings - Doc Type: Memo

Field and office procedures help CWCS
determine instream flow recommendations

Editor's Note: The following is a brief
description of procedures used by the
CWCB to develop instream flow recommen-
dations. The detail of each component will
be featured in future issues.

The Instream Flow statute sets forth
the guidelines for the administration
of Colorado's Instream Flow Program
(ISF Program). The statute vests the CWCB
with the exclusive authority to appropriate
and acquire instream flow and natural lake
level water rights. In order to encourage
other entities to participate in Colorado's
lSF Program, the statute directs the (WCB
to request instream flow recommendations
from other state and federal agencies prior
to initiating an instream flow appropriation.
The CWCB routinely requests instream flow
recommendations from the Colorado
Division of Wildlife (DOW), Colorado
Division ofparks and Outdoor Recreation,
:United States Department of Agriculture,
and United States Department ofInterior
(the "cooperating agencies").
Prior to appropriating an instream
flow water right, the statute requires the
CWCB to:
1) determine that the natural environ-
ment will be preserved to a reasonable
degree by the water available for the appro-
priation to be made;
2) determine that there is a natural
environment that can be preserved to a rea-
sonable degree with the CWCB's water
right, if granted; and
3) determine that such environment
can exist without "material injury to water
rights" [~ 37-92-102(3c), eR.S. (1990)1. The
CWCB makes these determinations based
upon a review of the supporting technical
data and a final instream flow recommenda-
tion prepared by the CWCB staff.
Determining the quantity of water
required to preserve the natural environ-
mentto a reasonable degree can be a diffi-
cult task. The CWCB, in cooperation with
the DOW, has developed standard field and
office procedures to ensure that each

instream flow appropriation is necessary and
reasonable and the amount of water recom-
mended is available for appropriation.
The established standard field proce-
dures concern selection of transect sites and
collection of hydraulic and biologic data.
Standard office procedures have been estab-
lished for determining biological instream
flow recofl1mendatlons using output from
R2CROSS and for analyzing water availabili-
ty.

Hydraulic
and biologic data
is generally col-
lected during a
single field visit.
Hydraulic data
collection con-
sists of setting up
a transect, sur~
veying stream
channel geome-
try and measur-
ing stream dis-
charge. Biologic
data is gathered to document the existence
of a natural environment. The biologic data
usually consist of a fish sample - collected

by electroflshing - and an aquatic inverte-
brate sample. A water availability analysis is
conducted to determine that water is physi-
cally available to satisfy the biologic recom-
mendation. Water availability analysis con-
sist of reviewing existing gage records,
and/or the use of standardized hydrologic
techniques such as areal apportionment or
synthetic streamflow modeling. The CWCB
also reviews the State Engineer's water
rights tabulation
and consult with the
Division Engineers
and local water com-
missioners to deter-
mine (1) what effect
the senior diversions
may have on a
stream reach, and
(2) if the instream
flow appropriation
would materially
injure the existing
water rights.
These proce-
dures ensure that instream flow recommen-
dations are scientifically sound and consis-
tent with statutory guidelines. .

The established
standard field proce-
dures concern selection
of transect' sites and
collection of hydraulic
and biologic data.

donations . . .
continued from page 1
new rights, and to some extent, deal with the
instream flow needs of federal and state
agencies. It also provides an opportunity for
members of the public to transfer water
rights to the Board for maintaining instream
flows.
The WAF assists the Board in improving
the priority of its instream flow water rights
and/or establishing new rights, as well as
meeting the instream flow needs offederal
and state agencies. It also provides an oppor-
tunity for members of the public to transfer
water rights to the Board in order to main-
tain instream flows in their area.
Our mission is clearly defined as pre-
serving the natural environment to a reason-
able degree, as defined by providing habitat
3

for fish and wildlife. However, many people
also see instream flows integral to the health
of their economies, beauty of their communi-
ties and quality oflife. .

Editors Note:
If you are interested in donating
your water, water right or interest in
water to the Board, please contact
Dan Merriman or Bahman Hatami
. at [phone]. The donation
process may take anywhere from a
few months to a few years, depend-
ing upon the complexity of the
donated water right. However, the
Board will do all it can to expedite
the process.