9571

• UCREFRP Catalog Number: 9571
• Author: Miller Ecological Consultants Inc.
• Title: Fryingpan-Roaring Fork Literature Review.
• USFW Year: 2002.
• USFW - Doc Type: Fort Collins, CO.
• Copyright Material: NO

1

U.S. Department of Interior, Bureau of Reclamation, Simons, Li and Associates Inc.,
Environmental Research and Technology, Inc. 1989. "Ruedi Reservoir, Colorado,
Round II Water Marketing Program, Final Supplement to the Environmental
Statement, Fryingpan Arkansas Project. Denver, Colorado.
r The
r
f thi
d
pu
pose o
s stu
y was to analyze three possible alternatives for water delivery
and one mitigation scenario. The No Action Alternative and Preferred Alternative are
considered along with the Preferred Alternative with Conservation Measures Alternative
as recommended by the United States Fish and Wildlife Service in the Biological
Opinion. Environmental impacts were expected due to decreases in Ruedi Reservoir
stage and streamflow patterns in the rivers downstream. The stream flows in the
Fryingpan River, and to a lesser degree in the Roaring Fork, would be decreased in wet
years and increased in dry years in comparison to the No Action Alternative. Summaries
are given concerning the potential monthly effects on streamflow in the Fryingpan and
Roaring Fork rivers. Changes in streamflow were expected to cause minor losses in fish
habitat.

Ruedi Reservoir
Predicted impacts on the reservoir resulted from loss of bottom area. The effects of this
action would be loss of rearing areas for juvenile trout, loss of feeding areas for adult
trout, reductions in macroinvertebrateproductlon and decrease in macrophyte production.
The magnitude of the effects would depend on the extent and duration of changes in
reservoir level. The loss of habitat would be mostly in the northern bays due to loss of
littoral areas. Average loss of total littoral areas in the reservoir would be 10
' increasing to 29% in dry years. The extent of this habitat loss was predicted to reduce the
numbers and or growth of trout.
Fryingpan River
The emphasis of this report was to use available data, much of which came from previous
studies, to predict how proposed changes in flow could impact the current physical and
biological conditions. The potential adverse effects from changes in flow regimes
included; a greater percent loss of incubating trout eggs, habitat loss for trout at various
life stages, loss of cover for fish, and reduction in benthic macroinvertebrate production.
During some months benefits to the fishery would come from additional habitat gained
due to increased flows.
Habitat loss for the limiting life stage of each trout species was calculated using IF1M.
Data was collected at two study sites, the Castle Rock and Old Faithful sites. No
significant habitat losses for rainbow or brown trout frY were predicted. Losses of habitat
for rainbow trout fry and juveniles in the 10% to 25% category were expected in 4
months in a dry year, 3 months in an average year. A wet year was expected to result in
some habitat gains. Brown trout fry could have losses of habitat during one or two
months in each type of year. The Preferred Alternative with Conservation measures was
not predicted to reduce the numbers of rainbow and brown trout fiy or juveniles.
Fryingpan-Roaring Fork Literature Review February 27, 2002
Miller Ecological Consultants, Inc. Page 1T