Evaluation of the portable furrow infiltrometer
Abstract Twenty infiltrometer tests were conducted to compare infiltration rates estimated by the recirculating infiltrometer (RIF) and the newly developed portable infiltrometer (PIF). Two types of furrows commonly used in the western United States; small and steep, and large and less steep; were considered in high and low infiltration soils. Comparison of the PIF and RIF infiltration rate measurements indicated that PIF was most accurate in estimating steady infiltration rates. Use of the PIF for predicting infiltration rate functions was not recommended because of the need for collecting accurate measurements early during the infiltration process. Considering ease of installation, accuracy in measuring steady infiltration rates, and ability to collect data during irrigation, the PIF is a promising device for use in surface irrigation management.
Recirculating furrow infiltrometer design guide
Determination of infiltration parameters is critical for the design and 
operation of efficient furrow irrigation systems. The complexity of the physical 
processes which govern infiltration in furrows, and the nonhomogeneous, anisotropic 
conditions which often exist in irrigated fields, have hindered the development of an 
infiltration theory which can accurately predict infiltration rates based on easily 
measured soil parameters. Therefore, the practicing irrigation engineer continues to 
depend on direct measurement of infiltration using infiltrometers or volume balance 
methods for determining field infiltration during continuous flow or surge flow furrow 
irrigation. Volume balance methods use advance, surface storage, inflow, and outflow 
data collected during an irrigation event to determine the infiltration parameters. 
Elliott and Eisenhauer (1983) outline the details of several volume balance methods for 
continuous flow irrigation. Latortue (1984) outlines a volume balance technique for 
estimating infiltration and surface storage for surge flow irrigation. The infiltration 
parameters determined from these methods are likely to be more representative of 
average field conditions than data obtained from an infiltrometer.
Designing furrow irrigation systems for improved seasonal performance.
ABSTRACT Atraditional approach to furrow irrigation system design was evaluated to determine its effect on the seasonal performance of a typical farmer-managed system. Results indicate the need for an improved design approach that better accounts for seasonal changes in field conditions. Recently, attention has been focused on the need for more wise and efficient use of water on the farm. Irrigated agriculture, in particular, is faced with the dilemma of using a diminishing supply of water to meet an increasing demand for food and farm income. Much of the responsibility to meet this challenge falls upon the agricultural engineering profession. Traditional methods of system design and operation need to be evaluated and new methods developed that will help to strengthen irrigated agriculture as an economically justifiable, productive, and socially responsible endeavor. Surface irrigation (used here to refer to surface flooding by gravity flow) is the method used on most of the world's irrigated land (Goldberg, 1974). Improving irrigated agriculture on a worldwide scale must address the problems related to surface irrigation. Many surface irrigation systems ideally can supply crop water needs at field application efficiencies of 70 to 85 percent (Willardson, 1972; and Merriam and Keller, 1978). Studies conducted around the world indicate typical efficiencies to be only 40 to 50 percent (Bos and Nugteren, 1974; Clyma and Ali, 1977; Kruse and Heermann, 1977; Clyma et al., 1975). Solving the problems of inefficient surface irrigation practices requires the use of good system design. A good irrigation system design is the product of a reliable design procedure and the appropriate application of that procedure. The design procedure should be based on a model that adequately predicts system hydraulics and performance. It is used to select the values of system and operational (or management) variables that constitute the right conditions for achieving a specified level of performance. If the system is built and given to the operator without instructions as to how the system should be operated, the system cannot be expected to function to produce the desired results. Traditionally, design procedures for surface irrigation have specified operational variables based on field conditions during the period of peak consumptive use of the crop (USDA, 1979; Corey and Hart, 1974; Withers and Vipond, 1974). Thus, the design does not account for the change in field conditions during a cropping season. In the case of the SCS method and various other empirical methods of furrow irrigation system design, operational variables are explicitly selected in the design process. However, when system and operational variables are specified and implemented based upon conditions existing in the field at one point in time, the resulting system performance may be poor. How do furrow intake rates and required water application depths vary on a typical farmer managed furrow irrigation system? What system performance would result if each irrigation, as scheduled by the farmer, were operated with the flow rate and inflow time designed for the peak capacity period? If seasonal variations in field conditions are considered in design, what changes in the system or its operation might be needed to achieve acceptable performance through the season? This study was conducted to address these questions.