Reconnaissance of sediment transport and channel morphology in the Lower Rio Bermejo Basin, Argentina - with a section on reconnaissance of the lower Rio Pilcomayo Basin, Argentina and Paraguay

Reconnaissance of sedimentation in the Rio Pilcomayo Basin, May 1975, Argentina, Bolivia, and Paraguay

“…The average annual discharge there is about 100 million tonnes 1/ per year (t/yr). That figure is calculated from the sediment-transport curve and the flow duration for the periods 1962-65, 1967-69 and 1971-72 and coincides with that given by Ritter (1976), which was based on a shorter period.…”

“…The observations of the previous reconnaissance of the Rio Pilcomayo (August -September 1974) can be found in the reports by Maddock (1974) and Ritter (1976). The observations in this report are limited to those made in May 1975.…”

“…The Rio's Pilcomayo "Superior" and "Inferior", however, had been previously visited on a trip during August and September 1974. That trip, which was described in reports by Maddock (1974) and Ritter (1976), was made during a period of law flow; the more recent trip was made during a time of flooding.…”

Geological Survey research 1978

“…To verify the satellite image interpretation proce-dure, approximately 15 percent of the study area was interpreted on high-altitude 1:120,000-scale photographs. Cropland area determined from the aerial photographs was compared with cropland area determined from a Landsat image of the same date (May 1975). A discrepancy of only 2 percent was found.…”

“…Rio Pilcomayo sedimentation J. R. Ritter (1977a) reported that results of a sedimentation reconnaissance of the Rios Pilcomayo Alto (Bolivia) and Pilcomayo Superior (Bolivia, Argentina, and Paraguay) made under the auspices of the Organization of American States (OAS) em phasized the need for a complete analysis of sedi ment movement in the basin before dams or irrigation projects are started. The brief study sup plemented an earlier reconnaissance (Ritter, 1977b) of the Rios Pilcomayo Superior and Pilcomayo In ferior (Argentina and Paraguay) made during a period of low river discharge. S. T. Algermissen, J. N. Jordan, and W. J. Spence (USGS), along with Bolivian coinvestigators Ramon Cabre, S. J. Flores, and Jose Flores, have started a project to assess the seismic hazard of the Cochabamba region of Bolivia.…”