FLOOD04810

• County: Pitkin
• Stream Name: Roaring Fork River
• Basin: Colorado Mainstem
• Title: Roaring Fork Multi-Objective Planning Project - Pre-Project Information
• Date: 4/1/1998
• Prepared For: Pitkin County
• Prepared By: State of Colorado
• Floodplain - Doc Type: Community File

5) Describe Transbasin Diversions
Using existing sources, tabulate and briefly describe the transbasin diversions
from the Roaring Fork and Fryingpan watersheds. Indicate the effects of those
diversions on streamflow, environment and stream stability. Identify other
factors, such as reservoir operations, agricultural practices and municipal
wastewater return flows, which may affect streamflow and stability.

6) Identification of water quality issues for specific locations
Review water quality issues at two (2) specific locations: Brush Creek from the
Town ofSnowrnass Village to the confluence with the Roaring Fork River and 7
Castles Creek to its confluence with the Fryingpan River. These sites have been
identified as being the sources of sediment loading into the Roaring Fork and
Fryingpan mainstems and should be analyzed for the seriousness of those impacts
and for mitigation recommendations.

C. Conclusions & Recommendations

1) Develop Stream Stabilization Alternative
Generate a list of alternative stream stabilization measures for each identified area
of stream instability. Compare alternatives in terms of costs, habitat and
recreation considerations, likelihood of long-term effectiveness, ease or difficulty
of installation, and environmental impacts. Develop decision-making methods for
choosing between alternatives and recommend best available alternative for each
stream reach.

2) Design Stream Stability Monitoring Program
Develop a set of scientific parameters to define a stream stability monitoring
program. Provide threshold standards for each of these parameters to determine
when a stream reach is stable, prone to instability, unstable, or highly unstable.
Describe the equipment, methodologies, expertise, timeframe and prerequisites to
installation and maintenance of a stream stability monitoring program. Provide
cost estimates for equipment purchase, staff time, maintenance needs and other
program elements.

3) Prioritize Locations for Monitoring and Mitigation
Determine appropriate locations for ongoing stream stability monitoring activities
based on access, physical factors, cost factors and streambed characteristics.
Determine appropriate mitigation locations based on need, likelihood of success,
access, cost, maintenance needs and other appropriate factors. Show locations for
monitoring and mitigation on maps and describe these locations.