Infiltration as a Dependent Variable in Modeling Furrow Irrigation
Most surface irrigation models assume that infiltration is independent of surface flow hydraulics. However, wetted perimeter has been shown to significantly affect infiltration in furrows....
Selenium: Essential Nutrient or Toxic Threat?
The essential nutrient selenium is believed responsible for numerous deformities, reproductive failures, and deaths of migratory birds at Kesterson Reservoir in the San Joaquin Valley,...
Steady State Fluid Transport Model for Plants
Knowledge of water potentials throughout the xylem and phloem elements as well as in individual cells is fundamental for understanding effects of water and temperature stress on transport...
Estimation of Mean Water Depth for Border Irrigation
The mean water depth for border irrigation is derived, using dam-break simple wave solution and boundary layer theory, as a function of inflow discharge, bottom slope, bottom roughness,...
Evaluation of Basin-Furrow Irrigation Systems
The division of the total flow into basin-furrows is analyzed using both energy and momentum principles. A zero-inertia model is applied to simulate the advance phase using different infiltration...
Estimating Number and Duration of On-Times for Surge Irrigation
Research shows surge flow can achieve efficient and uniform irrigation on some soils. However, most available information focuses on computerized analysis and modeling for research purposes....
Investigation of Main Supply Canal and Lateral Fluctuations
The Imperial Irrigation District and the U. S. Water Conservation Laboratory of Phoenix, Arizona are conducting a joint project to study the causes and effects of water level fluctuations...
Rating Curves for Adjustable Tricklers
This paper presents the approach and results of evaluating adjustable drip/trickle emitters to obtain rating curves. The emitter discharge depends on both system pressure and emitter opening...
Subsurface Drains Solve Groundwater Rise Problems
Four sub-surface drainage alternates were evaluated for lowering the rising water table. Horizontal gravity drainage system offered the best solution to the problem. Disposal of drained...
Surge Flow?Automation of Surface Irrigation?At Last
The studies which led to the development of Surge Flow at Utah State University, began as an effort to automate surface irrigation systems. The first prototype models, were electric control...
Theoretical Flow Model for Drop Structures
A theoretical model based on the momentum equation is reviewed for a trapezoidal weir drop structure operating in a trapezoidal channel. Preliminary qualitative results indicate agreement...
Flutter Derivatives from 14 Generic Deck Sections
The results of a series of wind-tunnel bridge-deck section-model experiments are discussed. Fourteen section models, seven with H-shaped cross-sections and seven with rectangular cross-sections,...
Wind Tunnel Investigation of a Twin Deck Suspension Bridge
Wind tunnel measurements of the response of a twin deck suspension bridge to dynamic wind loads are presented. The investigation was concerned with the determination of the deck response...
Furrow Modeling with Variable Hydraulic Characteristics
A zero inertia furrow irrigation model was developed to run on an IBM-compatible micro-computer. The depth gradient term of the momentum equation is approximated by averaging over the...
Are Soil Moisture Accounting Models Needed for the Real Time Forecasting of River Flows?
The difficulties inherent in using conceptual rainfall-runoff models in conjunction with filtering techniques, for the real time forecasting of river flows, are reviewed. The issue of...
Missouri River Basin Water Accounting System
A water accounting system was developed for the Missouri River Basin to establish an accurate and acceptable base of information describing water availability and uses, and to provide...
Optimizing a Minimum Instream Flowby
The Commonwealth of Virginia is currently investigating methods to establish minimum instream flow requirements which may be applied to flow allocations statewide. The Crump Creek Reservoir...
Mesonets--A Solution to Improving Flood Forecasting
Floods continue to cause major destruction annually despite the efforts of Federal water resources agencies. Improved flood forecasts can reduce flood damages and corresponding loss of...
The Northwest Watershed Research Center, 1959-86
Hydrologic research has been conducted on the Reynolds Creek Experimental Watershed by the Agricultural Research Service for nearly 27 years. Some noteworthy instrumentation, developed...
HEC-1 and HEC-2 Applications on the Microcomputer
The Hydrologic Engineering Center (HEC) has developed versions of the HEC-1 Flood Hydrograph Package and the HEC-2 Water Surface Profiles programs for MS/PC-DOS compatible microcomputers...
Return to search