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A preliminary study of sediment transport parameters, Rio Puerco near Bernardo, New Mexico
| Content Provider | Semantic Scholar |
|---|---|
| Author | Nordin, Carl F. |
| Copyright Year | 1962 |
| Abstract | Preliminary findings of a study of sediment transport in streams with high concentrations of suspended fine sediment indicate that for the Rio Puerco near Bernardo, N. Mex., the velocity varies logarithmically with depth, and the concentration distribution for several size classes of sand may be described by a conventional distribution equation if the fall velocity of the sand is corrected for the influence of the fine sediment. A corrected fall velocity, empirically defined for a temperature of 24° C and for concentrations of as much as about 150,000 parts per million, is given. Through the period of the study, the channel of the Rio Puerco changed rapidly. The bed material varied from cohesive fine material to coarse sand. At the beginning of the study, the sand bed of the channel was impregnated with clay, and the clayimpregnated layer acted as an effective "armoring" which persisted for several weeks, forming a cohesive boundary for the flow and limiting the availability of sand for transport. For the last several observations, a "headcut" in the armored layer had progressed upstream into the study reach. The influence of the headcut was reflected in an increase in the water-surface slopes and in the concentrations of suspended sand. Flow resistance, as measured by Manning's n, was approximately constant and was independent of the condition of the bed (cohesive or noncohesive) and of the average size distribution of the bed material. Some observations of extreme sediment concentration are cited, and some of the problems involved in attempting to explain or to predict sediment transport rates for extreme conditions are discussed briefly. The rapid changes in the channel geometry and in the characteristics of the bed material, and the extreme sediment concentrations that were observed, reflect conditions which, in general, are not described adequately by conventional sediment transport relations. Observations in this report point out the extreme complexity of the natural processes operating in the Rio Puerco watershed and indicate the need for a better understanding of the factors controlling the flow and the sediment transport in ephemeral streams. |
| File Format | PDF HTM / HTML |
| DOI | 10.3133/pp462c |
| Alternate Webpage(s) | https://permanent.access.gpo.gov/gpo83865/report.pdf |
| Alternate Webpage(s) | https://digitalrepository.unm.edu/cgi/viewcontent.cgi?article=1182&context=ce_etds |
| Alternate Webpage(s) | https://doi.org/10.3133/pp462c |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
