Estimating the savings from improving pumping plant performance.

This brochure describes a method to estimate the cost of pumping water and to compare the amount of energy used to that for a well maintained and designed pumping plant. The results can help determine the feasibility of repairing the pumping plant

Irrigation Pumps - Preserving Performance

This paper describes how pumps must be matched to operating conditions and power units to provide the desired performance and efficiency. We have recently seen installations where one or more components are not properly matched causing higher than necessary pumping costs. Inspection and maintenance of systems and measurement of flow and pressure will go a long way toward monitoring if the proper conditions are being met. This paper also covers types of pumps, pump components, pump curves, impeller speed and trim, pump staging, affinity laws, pump drives, power units, cavitation, and net positive suction head

A Physically Based Two-Dimensional Infiltration Model for Furrow Irrigation

A two-dimensional physically based infiltration model was developed for furrowirrigation. Infiltration was simulated using the Green-Ampt infiltration method. The Green-Ampt infiltration parameters are available from numerous sources, unlike the Kostiakov infiltration parameters. Simulation tests showed the two-dimensional model capable of estimating cumulative infiltration volume within 8% compared to simulated infiltration using the finite element model, Hydrus-2D. Application of the two-dimensional model in a surface irrigation advance model allows irrigation performance parameters to be predicted without extensive soil experiments

WELFARE DIFFERENCES BETWEEN GROSS WATER PUMPED AND CONSUMPTIVE USE AS ALTERNATIVE POLICY CONTROL VARIABLES TO MEET AQUIFER MANAGEMENT OBJECTIVES

The welfare cost of using gross water pumped instead of consumptive use as a control variable to meet consumptive use goal was estimated for Southwestern Nebraska. The results show that the widespread use of gross water as a policy control variable substantially overstates the welfare cost of reducing consumptive use.Resource /Energy Economics and Policy,

A Physically Based Two-Dimensional Infiltration Model for Furrow Irrigation

A two-dimensional physically based infiltration model was developed for furrowirrigation. Infiltration was simulated using the Green-Ampt infiltration method. The Green-Ampt infiltration parameters are available from numerous sources, unlike the Kostiakov infiltration parameters. Simulation tests showed the two-dimensional model capable of estimating cumulative infiltration volume within 8% compared to simulated infiltration using the finite element model, Hydrus-2D. Application of the two-dimensional model in a surface irrigation advance model allows irrigation performance parameters to be predicted without extensive soil experiments

Effect of Limited Water Supplies on Center Pivot Performance

When appropriately designed and operated, center pivot irrigation systems can efficiently irrigate many crops grown on diverse soil and terrain conditions. However, a significant number of pivots are not supplied with an adequate water to operate as envisioned. We simulated the hydraulics of a center pivot irrigation system, including the pump curve, flow rate, pipeline hydraulics, pressure regulators, nozzle flow rate, and irrigation application uniformity. This was used to analyse the performance of a center pivot for a sloping field for both adequate and inadequate water flow rate. The performance was simulated for a range of inlet pressures when pressure regulators were used and for systems without pressure regulators. Inadequate inflow causes major degradation of the uniformity of water application and the ability of the system to meet crop needs. Results show that regulators improve uniformity for high-flow conditions but do not improve the discharge uniformity when inlet pressures—and therefore system inflow—drop below design specifications. The variability of discharge at the distal end of the pivot is less for unregulated conditions than when regulators are used for limited inflows

Performance of Seedigated and Conventionally Planted Crops

Seedigation is the use of a moving sprinkler irrigation system to broadcast seeds on the soil surface. Seed germination, plant characteristics and yield for grain sorghum, winter wheat and soybeans that were seedigated and conventionally planted are compared. When the seeding rates for seedigation were increased above that for conventional planting, and adequate moisture was available for germination, grain sorghum and wheat seedigated on tilled surfaces produced yields similar to conventionally planted crops. Seedigation of soybeans into fallow conditions, or when used as a relay crop, was unsuccessful. Shallow disking following seedigation did not improve germination or yield of grain sorghum or winter wheat. Using seedigation to plant wheat into soybeans offers good potential. Seedigating wheat into dense grain sorghum canopies was less successful

Performance of Seedigated and Conventionally Planted Crops

Seedigation is the use of a moving sprinkler irrigation system to broadcast seeds on the soil surface. Seed germination, plant characteristics and yield for grain sorghum, winter wheat and soybeans that were seedigated and conventionally planted are compared. When the seeding rates for seedigation were increased above that for conventional planting, and adequate moisture was available for germination, grain sorghum and wheat seedigated on tilled surfaces produced yields similar to conventionally planted crops. Seedigation of soybeans into fallow conditions, or when used as a relay crop, was unsuccessful. Shallow disking following seedigation did not improve germination or yield of grain sorghum or winter wheat. Using seedigation to plant wheat into soybeans offers good potential. Seedigating wheat into dense grain sorghum canopies was less successful

Needs Assessment: Watershed Science for Water Resources Directors

We conducted a needs assessment to identify watershed science training needs for locally elected directors of Nebraska\u27s 23 natural resources districts (NRDs). We interviewed NRD staff and surveyed NRD directors to determine training needs and identify relevant topics and preferred delivery formats. We found that training would be valuable; however, directors are busy, meaning that opportunities for training are limited. Additionally, we learned that directors rely on printed material and other NRD personnel for watershed science information. Therefore, web-based information may be most useful if designed for collaborative learning through hybrid delivery during regular NRD activities. Our findings are relevant to current and future regulatory systems reliant on locally elected boards

Irrigation Systems Management

Like most textbooks, this book grew out of our desire to have written material that matches the educational needs of both the students and the instructor of a college course, in this case a course entitled Irrigation Systems Management. The book is the culmination of course notes which have been in development and use for nearly 30 years. The emphasis of this book is on the management of irrigation systems that are used for agricultural crop production. There are two distinct components of the book, starting with the soil-water-plant-atmosphere system and how soil water should be managed to achieve the desired crop production outcomes. This includes in-depth presentations on soil water storage and movement, plant water use, managing the soil water reservoir through irrigation scheduling, and salinity management. The book then shifts to the second component, which is the description and management of the various forms of agricultural irrigation systems along with their water supply. Whether it be a surface, sprinkler, or microirrigation system, the irrigation manager must not only know how much water to apply but also how to manage the system itself to achieve efficient application. High application efficiency can only be realized by minimizing runoff, deep percolation, evaporation, and drift onto non-target areas. Since energy costs are an integral part of the management equation, one chapter in the book deals with the hydraulics and energy requirements of pumping and distributing water. One of the key themes spread throughout the book is providing guidance to irrigation managers on how to improve irrigation water productivity (production per unit of irrigation water) and minimize water resource contamination. Our goal is for the reader to understand the complexities of irrigation systems and how they are to be managed to meet the water needs of the crop production system. This is not an irrigation engineering design book; we have purposely minimized the presentation of design steps and the supporting equations. The intended audience of the book is upper-level undergraduate students and graduate students who are pursuing degrees in Agricultural or Natural Resource Sciences. Example majors include Agricultural Systems Technology, Agronomy, Crop Science, Mechanized Systems Management (or equivalent), Natural Resources Management, Soil Science, and Water Science. We expect the reader to have a basic understanding of soils, crops, physics, and the application of algebraic equations. We have also tried to add enough advanced material to challenge graduate students when the book is used in courses that are taught simultaneously at the undergraduate and graduate level. We hope the book will match the needs of students who plan to work in irrigation and related industries, university extension and outreach, private consulting, government service, or production agriculture and that it will continue to serve as a useful reference to them following completion of their formal education