Polyacrylamide Decreases Furrow Erosion
Erosion from furrow irrigated land is a serious problem in southern Idaho and several other areas. Polyacrylamide, a very long chain polymer, increases aggregate stability and flocculates...
A New Look at the Potential of Hygroscopic Seeding in Summertime Convective Clouds
Hygroscopic seeding was conducted in the sixties and early seventies in the USA, but since then, most cloud seeding efforts have used glaciogenic seeding materials, usually silver iodide...
Selenium in Soil, Water, Sediment, and Biota of the Lower Sun River Area, West-Central Montana
A U.S. Department of the Interior study started in 1990 examined the source, movement, fate, and possible biological effects of selenium associated with irrigation drainage from the Sun...
IRRICAD ? Computerized Irrigation Design
IRRICAD is a software program that helps irrigation designers by using a computerized systems approach to design. The program features drawing CAD input, interpolation of elevation data,...
Soil Bulk Density Sampling for Neutron Gauge Calibration
The ASCE Task Committee on Neutron Gauge Calibration met in Logan, Utah in July 1992 to investigate the various methods of soil sampling, installation of access tubes, effect of various...
Measuring Soil Bulk Density Profiles with a Single Probe Gamma Density Gauge
Calibrating neutron depth gauges for measuring soil water content profiles requires soil bulk density data. In this study, the feasibility of using a single probe gamma density gauge to...
Error Analysis of Bulk Density Measurements for Neutron Moisture Gauge Calibration
Six bulk density sampling methods were evaluated for use in neutron gauge calibration. All six methods provided estimates of bulk density which were generally within 5% of bulk density...
Effect of Moisture and Bulk Density Sampling on Neutron Moisture Gauge Calibration
Three moisture and bulk density sampling methods were evaluated for use in neutron gauge calibration. Each of the methods was comprised of a single core or portions of a core taken during...
London Linkage
Although it measures just 1.8 km, the Limehouse Link tunnel in London is both a complex engineering project and a gateway to urban renewal. The link is a $350 million highway tunnel connecting...
Optimization Modeling for Sedimentation in Alluvial Rivers Considering Uncertainties
A nonlinear optimization model is formulated for determining optimal reservoir releases to minimize channel bed aggradation and degradation in downstream rivers. The model is based upon...
A Model for Low-Drag Landslides
Field observations and experimental records indicate that the primary mode of motion of many large landslides is that of sliding rather than flowing. Most of the shear during sliding is...
Simulation of Subsurface Drainage of Highway Pavements
An analysis of the drainage of a pavement system from initial saturation incorporates a realistic assessment of the drainable porosity of the base. This analysis indicates that if a granular...
The Tidal Inlet Characteristics of a Small California Estuary
The inlet channel of the Russian River estuary in Northern California is subject to frequent closure. The formation of a barrier beach across the inlet channel creates ponding of the river...
San Francisco Bay and Delta Oil Spill Fate Studies Part I: Hydrodynamic Simulation
A two-dimensional vertically-averaged finite element model was used to simulate the hydrodynamics in San Francisco Bay and Delta to support oil spill fate studies. Simulations were performed...
San Francisco Bay and Delta Oil Spill Fate Studies Part II: Oil Spill Simulation
Because of the presence of oil refineries and significant tanker and barge traffic in the bay and delta region, the possibility of a moderate or major spill in the area must be considered....
Incipient Motion in Gravel-Bed Rivers
Incipient motion processes are reviewed for bed material in gravel-bed rivers. Prediction difficulties are identified. Research results are reported for field and flume studies to investigate...
Sediment Budgets in Gravel Bed Streams
A sediment budget/mass balance technique is presented for use in assessment of sediment transport by river reach in gravel bed streams. Selection of appropriate gravel bed transport equations,...
Extreme Events and Coastal Wetlands
Temporal ecosystem behavior in tidal wetlands can be static, dynamically stable, progressively changing, or subject to catastrophic change during extreme events. Catastrophic change in...
Bed Sediments Size Changes, Atchafalaya River
During low flows of 1989 and 1991, we collected bed sediment samples from the thalwegs of the Mississippi River from Cairo, Illinois, to Head of Passes and along the Atchafalaya River...
A Study of Lateral Bed Slopes Developed at Bend
A study was conducted to compare seven actual cross section profiles of Philip Bayou Realignment with the lateral bed slopes estimated from the model derived by Ikeda titled `Sediment...
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