Water Optimizer   

A Decision Support System for Agriculture Producers with Limited Irrigation Water. 


A Policy Analysis Tool for Water Policy Decision Makers

Water Optimizer is a suite of optimization programs to predict the profit maximizing cropping strategy and corresponding amount of applied irrigation water when water supplies are limited. The Water Optimizer Suite consists of four separate, but similar models; the basic Water Optimizer, a multi-field Water Optimizer, a multi-year Water Optimizer and an independent budget calculator. The single-field single-year model seeks to maximize the average annual net return subject to water supply constraints and user specified cropping limitations. The single-field single-year model is the platform for which the multi-year and multi-field tools are built upon.

The Water Optimizer tool was developed to assist in addressing water shortages created by drought and interstate water rights litigation. The current model released November 2010, supports all 93 Nebraska counties.

These tools are Microsoft Excel spreadsheets that allow users to describe a field in terms of soil type, irrigation system options, well and pump characteristics and water supply. Irrigation options include center pivot or gravity irrigation systems, well or canal delivery, and systems powered by electricity, diesel or natural gas. After entering this basic information, producers can either use the default values in the model or enter their own production costs, irrigation costs, crop prices and crop choices. After these parameters have been set, the program calculates what crops and irrigation application levels will be most profitable with the amount of land and water available.

Each tool evaluates several crop options. Irrigated crops include: alfalfa, corn, edible beans, soybeans, grain sorghum, sugar beets, sunflowers, wheat and canola and camelina. Dryland crops include: alfalfa, corn, soybeans, grain sorghum, sunflowers, wheat and ecofallow.

We have developed the optimization programs into an Excel model where we use the nonlinear version of the “Solver” add-in to determine the optimal mixture of crops and to distribute the water. We have found this to be robust and relatively easy for user operation. Many of the required functions for modeling the response have been built into Visual Basic functions in Excel such that they are easily called and better documented than many spreadsheet applications. PLEASE KEEP THE FILENAMES THE SAME AS THEY ARE DOWNLOADED HERE. This will allow to the MACROS to run flawlessly.

Initial Developers

• Derrel Martin, Professor, UNL Biological Systems Engineering
• Ray Supalla, Professor, UNL Department of Agricultural Economics
• Scott Nedved
• Brian McMullen

Other Contributors

• Chris Thompson, Research Associate – UNL Department of Agricultural Economics
• Gary Hergert, Agronomist, UNL Panhandle Research Center
• Paul Burgener, Market Analyst, UNL Panhandle Research Cenenter

Limitation of Liability
The University of Nebraska and Nebraska Cooperative Extension shall have no liability of responsibility to the user or any other person or entity with respect to any liability, loss, or damage caused or alleged to be caused, directly or indirectly, by this computer program. All computer programs distributed by the University of Nebraska are on an "as is" basis without warranty.