Improving Drainage with Laser Controlled Land Grading in the Red River Valley of the North
This paper evaluates a laser controlled land grading project in the Red River Valley of the North. Graded fields are compared with ungraded fields to measure changes in dryland crop yields...
Lessons from the Failure of a Needle Valve
In 1984 a manually operated, hydraulically actuated 66-inch needle valve ruptured due to water hammer. The circumstances that caused the failure were reconstructed through extensive analysis...
Non Linear Economic Models for Crop Production
Most economic models for crop production rely on the traditional linear programming approach, in spite of the fact that the objective function is almost always non linear. This paper briefly...
Delivery System Management Via Dynamic Programming
Management of irrigation water delivery systems may involve allocating limited water supplies over both time and space under uncertain future demands. The physical delivery systems are...
Interactive Surface Irrigation Design and Evaluation Software
This paper outlines the features and capabilities of a comprehensive personal computer software system for use by irrigation engineers in design and evaluation of continuous and surge...
Bowen Ratio and Penman: Australian-California Tests
Results are presented of evapotranspiration (ET) studies conducted in Davis, California and at two locations in Australia. Good agreements were obtained in early comparisons of Bowen Ratio...
The Relationship of Benefits to System Size for Irrigation Projects
This paper presents a generalized linear programming (LP) and farm budget model for optimization of on-farm irrigation benefits resulting from variations in irrigation project size. The...
Weather Modification Versus Drought?No Contest
The Colorado River Municipal Water District has sponsored a summertime West Texas cloud-seeding program to increase rainfall in each year since 1970. Because of the program's...
Evaluation of Methods to Determine Peak Period Irrigation Water Requirements
Methods for estimating the peak period irrigation water requirement were evaluated as a component of the review of irrigation facility sizing criteria conducted for the Engineering and...
Satellite Remote Sensing for Regional Crop Inventories
LANDSAT 4 and 5 Satellite spectral images of the Columbia Basin were obtained during the 1984, 1985 and 1986 growing seasons by Cropix, Inc. of Hermiston, Oregon. A field classification...
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,...
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....
Establishing a Monitoring Program for Formulating Water Quality Objectives in a Transboundary Reach
A systematic approach to the establishment of a monitoring program for formulating water quality objectives in the Similkameen River should include the following interactive steps: 1)...
Spread Sheets for Irrigation and Drainage Projects
Land use planners as well as planners from other disciplines use overlays for site analysis but these are usually a qualitative display. Recently the advent of spread sheets coupled with...
Water Table and Salinity Movement in a Silty Clay Soil
The movement of the water table and profile salinity in a shallow drained soil in permanent pasture overlying an artesian aquifer was observed. Soil samples were taken before and after...
Physical Model Verification of a Coastal Discharge
A 1:75 scale physical model of a thermal discharge into a rocky, semi-enclosed bay was verified against extensive field data. The model accurately reproduced the prototype temperature...
Redundancy Evaluation of Existing Bridges
The redundancy of an existing bridge can only be correctly assessed by considering the full superstructure as a single entity. Any formulation based on the analysis of bridge components...
Evaluation of Corroded Steel Bridges
In the United States there is a large inventory of corroded steel bridges. The evaluation of these existing bridges is difficult when considering all the uncertainties involved in deterioration....
Three Automatically Erected Folding Spans
The U. S. Navy has identified three rapidly erected bridges. Each is capable of spanning 400 feet (120 m) with a 70 ton (63 tonne) live load at mid-span. Each will also fold into a 15...
Prediction of Deformations Due to Heat Curving
This paper summarizes the state of the art in the thermal deformation techniques. Alternate analytical methods are described. The limitations and accuracy of these models are noted, and...
Return to search