GWPATH: Ground-Water Flow Path Analysis
GWPATH is an interactive software package for estimating horizontal fluid pathlines and travel time in fully saturated groundwater flow domains. GWPATH was developed for the IBM PC-AT...
A Vectorized Polynomial Preconditioned Conjugate Gradient Solver Package for the USGS 3-D Ground-Water Model
A vectorized polynomial preconditioned conjugate gradient (PPCG) numerical algorithm is presented as an additional solver package interfaced with the Modular Three-Dimensional Finite Difference...
Reef Breakwater Response to Wave Attack
A method of predicting stability of a class of low-crested rubble mounds referred to as reef breakwaters is presented. Findings are based on a study which included an extensive series...
Unconventional Rubble-Mound Breakwaters?Concerns
A Seminar on Unconventional Rubble-Mound Breakwaters was held in Ottawa, Canada, on the 15th and 16th of September 1987. This paper is an attempt to summarize the general discussion that...
Comprehensive Rehabilitation Results From Stege Sanitary District
Seven sewer agencies, including Stege Sanitary District, in the East Bay of the San Francisco Bay Area embarked on a 20-year capital improvement program in 1987. The 300 million construction...
Simple Furrow Advance Ratio Evaluation Technique for Upgrading Management
A simple procedure using the Advance Ratio (AR) is presented. It utilizes on-farm gathered information of advance time, water application time, and depth applied for furrow irrigated field....
Evaluation of Infiltration Equations Used in Surface Irrigation
Computer simulations of an irrigation event were conducted using 6 full hydrodynamic models. All 6 models used the same surface flow equations and a different infiltration component. The...
Hydraulic Studies of Surface Drainage from Level Furrows
Field studies have been completed to quantify the surface drainage phenomenon from level furrows which were rapidly flooded and then drained from the inlet end of the furrow. The proportion...
Furrow Irrigation Performance Using Real Time Control
Computer simulations were conducted, using a simple feedback control algorithm, to determine the potential for improvement of irrigation performance using real-time feedback control. Field...
Surface Water-Groundwater Relations for Open Channels
For losing channels with clean wetted perimeters (no clogging layers), the seepage rate varies essentially linearly with depth to groundwater if the groundwater is relatively shallow,...
Simulation of Contaminant Transport Using NMOL Technique
In this paper, a new numerical method, called Numerical Method of Lines (NMOL), is used to solve initial-boundary value problems for solute transport in soils. The simulation results are...
Use of the Penman Equation in Inter-Mountain Valleys
H.L. Penman equation as well as the J.L. Monteith version of this equation were compared under the advective conditions of the Grand Valley of Colorado. The wind function in the general...
Proposed Improvements in Lateral Canal Operations
Uniform and flexible supplies of irrigation water are required for farmers to make the best use of their on-farm application systems. Results of a study of deliveries at the lateral canal...
Random Characteristics of Sediment-Laden Flows and the Techniques of Effective Sediment Exclusion on Dujiangyan Irrigation Project in China
The irrigation system is over 2,200 years old and discharges water at a rate of 340-740 m3/s from the Minjiang River. The average slope of the river...
Large Scale Evapotranspiration from Remotely Sensed Surface Temperature
Large scale evapotranspiration requires a blend of ground-based and remotely sensed data. To evaluate the utility of the extension from a small to a large scale, studies were conducted...
Measurement Systems in the Hapex-Mobilhy Regional Evapotranspiration Experiment
The HAPEX-MOBILHY (Hydrologic-Atmospheric Pilot Experiment - Modelisation du Bilan Hydrique) regional evapotranspiration experiment was conducted in the south-west of France during the...
Bulk Stomatal Resistance in Operational Estimates of Evapotranspiration
General relationships for estimating canopy or bulk stomatal resistance and aerodynamic resistances of grass and alfalfa reference crops for use in the Penman-J.L. Monteith equation are...
Ultrasonic Flow Meter Testing
Six ultrasonic flow meters were tested in a hydraulics laboratory. Accuracies better than 2% were obtained with two transit-time meters on 14 inch diameter steel tubing. Poorer accuracies...
Visual Estimates of Flume and Weir Operating Conditions
Laboratory studies were conducted on a rectangular broad-crested weir to determine the effects of entrance and exit conditions on the prediction of discharge and required energy loss....
Achieving Accurate Irrigation Water Measurements with Propeller Meters
Propeller meters are now being used extensively to help quantify and manage the huge but poorly distributed water supplies available to irrigated agriculture in the western states. Careful...
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