FLOOD04263

• County: Statewide
• Basin: Statewide
• Title: Design of Open Channels
• Date: 10/1/1977
• Prepared By: USDA Soil Conservation Service
• Floodplain - Doc Type: Educational/Technical/Reference Information

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Analysis of Channel Stability

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With the longitudinal profiles, logs and laboratory test data available,
the geologist and engineer are in a position to make an analysis of the
stability of the proposed channel improvement. In addition, information
is needed on the design discharge if bed-material load is not involved
as a problem, and the hydrographs for design as well as more frequent
discharges if bed-material load has been determined as a problem. Chapter
6 of this Technical Release or designated supplements are to be used for
determining the stability of channels that are not affected by bed
material transport. NEH, Section 3, Chapter 4, is to be used for the
analysis of bed-material transport that may affect channel stability.

Report Outline and Documentation

The ~ongitudinal profile, the plan view, logs, field and laboratory test
results, and stability analysis are to form the documentation for a brief
report based upon the following outline. Geologists and engineers are
both involved in an analysis of these problems. They should work closely
together in the determinations and report preparation.

A. Conclusions and Recommendations

B. Description of the geomorphology of the channel improvement
area

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Basis for stratigraphic unit delineation with reference to
longitudinal profiles or reasons for lack of stratigraphic
unit delineation.

C. Copies of logs and test data

D. Criteria used to establish stability

I. Condition of flow to be used in stability analysis: clear
or sediment-laden water. Basis for criteria used.

2. Bed material evaluation procedure used among those recom-
mended in NEH, Section 3, Chapter 4.

E. Stability analysis

I. Stability under proposed as-built conditions

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