11 ‎(2)‎

• Board Meeting Date: 11/18/2007
• Description: ISF Section - Contested Instream flow Appropriation Hearing - Badger Creek
• Board Meetings - Doc Type: Memo

Insti•eam Flow Recommendation(s)
BLM recommended an enlargement of 2.50 cfs during the summer, based on its August 23, 2005 and
August 14, 2004 data collection efforts (see Appendix). The modeling results from this survey effort are
within the confidence interval produced by the R2Cross model.
Land Status Review
Total Length Land Ownership
U er Terminus Lower Terminus (miles) % Private % Public
Spring complex in
SE/4 SE/4, Section Confluence with 17.7 10% °
90 /o
Arkansas River
13, TS1N R10E
The 90% public land ownership is comprised of USFS (52%), BLM (26%), and State (12%).
Biological Data
The BLM has conducted field surveys of the fishery resources on this stream and have found a natural
environment that can be preserved. As reported in the letter from BLM to the CWCB "Badger Creek is a
moderate gradient stream with small substrate size that occasionally experiences very large flood events.
The stream supports riparian communities consisting of cottonwood/coyote willow, willow/alder, and
mesic grasses." Fishery surveys indicate that the stream environment is presently in stable condition, and
supports aself-sustaining brown trout fishery. Channel stability, bank stability, food supplies, and water
quality are good for salmonids. However, the fishery is limited by a high silt load and occasional high
stream temperatures. Accordingly, it is important to provide streamflows that keep stream temperatures
low and that flush sediments from the system." (See Fish Survey in Appendix B).
Field Survey Data
BLM staff used the R2Cross methodology to quantify the amount of water required to preserve the natural
environment to a reasonable degree. The R2Cross method requires that stream discharge and channel
profile data be collected in a riffle stream habitat type. Riffles are most easily visualized as the stream
habitat types that would dry up first should streamflow cease. This type of hydraulic data collection consists
of setting up a transect, surveying the stream channel geometry, and measuring the stream discharge. The
appendix contains copies of field data collected for this proposed segment.
Biological Flow Recommendation
The CWCB staff relied upon the biological expertise of the cooperating agencies to interpret output from the
R2Cross data collected to develop the initial, biologic instream flow recommendation. This initial
recommendation is designed to address the unique biologic requirements of each stream without regard to
water availability. Three instream flow hydraulic parameters, average depth, percent wetted perimeter, and
average velocity are used to develop biologic instream flow recommendations. The CDOW has determined
that by maintaining these three hydraulic parameters at adequate levels across riffle habitat types, aquatic
habitat in pools and runs will also be maintained for most life stages of fish and aquatic invertebrates
(Nehring 1979; Espegren 1996).