Dynamic Perspective on the Capillary Barrier Effect at the Interface of an Upper Fine Layer with a Lower Coarse Layer
The theoretical principles behind the determination of infiltration rate into a coarse layer overlain by a tight layer are reviewed. As a descending unsaturated wetting front hits the...
Kinematic Mixing in Stratified Aquifers
The mixing process in heterogeneous aquifers is presented as the bending and stretching of material lines. A linear mixing efficiency is defined in terms of the mean values of a unit length...
Retrofitting a Detention Facility for Improved Quantity Control
Historically, detention facilities in the U.S. were first designed, constructed and operated for the single purpose of flood control. This led to a second phase, in which recreation and...
Computerized Maintenance Planning for Agency-Managed Irrigation Systems
Computerized maintenance planning has been established to facilitate: (1) preparation of the 'Catch-Up' Maintenance Plan using the field data collected while conducting the Diagnostic...
Managing Urban Growth an Irrigation District's Perspective
Urban growth within the Turlock Irrigation District has converted some property from agricultural to urban use. The District has established policies and developed documents and procedures...
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...
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,...
Streamflow Depletions Resulting from Ground Water Transfers
An application to move the point of diversion of a quasi-municipal ground water right from about 4.8 km to a second well about 0.3 km from a river channel was made in the Reno/Sparks,...
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...
Getting Along: The Geotech and the CM
The opinions of geotechnical engineers are usually respected within a consulting firm, but when such a specialist gets out in the field, he or she is seen as merely part of the backup...
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...
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....
Return to search