1400 ‎(2)‎

• UCREFRP Catalog Number: 1400
• Author: Simons, D. B., et al., ed.
• Title: Proceedings
• USFW Year: 1980.
• USFW - Doc Type: Workshop on Downstream River Channel Changes Resulting From Diversions or Reservoir Construction.
• Copyright Material: NO

7. Estimate sediment loading and the associated impacts on the
study reach during the construction phase (this requires site
data).

8. Estimate sediment loading to the river system during the
construction phase.

9. Establish the resistance to flow equations and sediment
transport characteristias for the study reach.

10. Conduct a qualitative morphological analysis (degradation,
aggradation, p1anform change, and bank stability) of the
system considering the clear water release from the dam. The
changes in flow over the long term future should be assessed.
The analysis would provide information on the expected bed
profile and cross section and bed material distribution over
time.

11. Evaluate the changes in the hydraul ic parameters that affect
the fish habitat utilizing a water-sediment routing program.

12. Conduct an initial thermal study of the temperature regime in
the study reach and the impacts of the reservoir. If changes
in thermal regime are found to be significant, a more detailed
study will be necessary that considers the thermal routing in
the system and selected withdrawal of water from multilevel
intake structure from the reservoi r to improve the thermal
regime. This requires a mathematical model study.

13. Use a mathematical model if a more detailed study of the
thermal regime is required to identify the potential thermal
problem associated with fisheries. Suggestions to modify the
position and openings of the multilevel intake should be made
if the study shows that serious temperature effects occur.

14. Evaluate one proposed construction plan and, if required,
recommend alternatives for evaluation.

---lS.--prepar~ reports documenting the results of analysis and
recommendations.

PROPOSED APPROACH

Storage and release of water from a reservoir will have effects on
instream flow, discharge rates, channel morphology, velocity,
substrate, depth, top width~ and temperature. The modification of flow
in a reach below a reservoir also may have both beneficial and adverse
effects on the fisheries over time. The hydraulic, morphological, and
thermal changes, as well as channel stability, .are functions of
hydrologic changes. A systematic approach to the analysis of the
hydrologic, hydraulic, sedimentation, morphological, and thermal changes
is requ; red to adequately evaluate the potential effects on the creek
and its fish habitat.

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