SURDEV

Content of the package

The SURDEV computer package was developed by the International Institute for Land Reclamation and Improvement (ILRI), Wageningen Environmental Research and the Institute of Land and Water Management of the Catholic University of Leuven (ILWM), Belgium, in 2001. SURDEV consists of three software programs: BASDEV (for level basins), BORDEV (for sloping borders) and FURDEV (for graded furrows).

Background

Surface irrigation relies on gravity to spread water over the farmers’ fields. Following the pull of gravity, the water flows over the fields from one end to the other, infiltration into the soil as it goes. The most common surface irrigation techniques are level basins (with or without level furrows), sloping borders and sloping furrows to distribute irrigation water. The purpose of all of these techniques is to supply water in the right quantity, at the right time and in an even layer, to achieve a uniform crop stand and minimise water losses. Success of the techniques depends on a proper design and operation of surface irrigation systems at field level, to help farmers achieve good crop yields, use precious water resources more efficiently and limit waterlogging and salinization of the soil.

For decades, engineers have been developing mathematical models of the entire process of surface irrigation to improve irrigation efficiencies in the farmers’ fields. The many variables involved in these models include field dimensions, field slope, flow rate, cut-off time, soil-infiltration and flow resistance. Interactions between the variables determine advance time, recession time, infiltrated depths and corresponding irrigation efficiencies and uniformities. The software included in SURDEV will help users to evaluate the effects of certain decisions in the design and operation of the irrigation process on the efficiencies and uniformities. The user should however realize that the computer models are simplifications of the real world. Basdev, Bordev and Furdev assume uniform conditions in time and space. In reality one knows that infiltration rates, for example, may vary considerably within a single field and between irrigations. It is therefore important to be aware of the capabilities and limitations of the presented programs and to urge the user to apply the models only to the situation foe which they were designed.

Theory and examples and manual

The SURDEV software was designed to run under 32-bit Windows. The software is accompanied by ILRI Publication 59 which contains theory, examples and the manual for the computer models. It can be downloaded without costs: ILRI Publication 59: SURDEV - Surface Irrigation Software.

Installation and running the SURDEV software

Download the zip-file SurdevInstall.zip from the link on this page. Unzip the contents into a folder called Surdev on a local drive. Execute the file named Surdev.exe and select one of the three modules Basdev, Bordev or Furdev. Proceed by selecting a pre-programmed example or start a new example under Files, Load or type a new file name in the text box. The Surdev publication 59 contains detailed information about the pre-programmed examples that come with the software.