Project Background

Project Background

The NAWMN* Project

*Since it has grown to over 1400 participants, it's no longer a demonstration, it's a network! Thus the NAWDN has undergone a name change to Nebraska Ag Water Management Network (NAWMN).

The Nebraska Ag Water Management Network (NAWMN, Irmak (2005)) project is designed for encouraging the adoption of newer technologies that will enable farmers to use water and energy resources associated with irrigated crop production efficiently.

Education and information about the use of appropriate technologies are delivered to agriculture professionals and irrigators through the NAWMN. The NAWM Demonstration Network project established a system for testing cutting-edge technologies and creating a network with growers, UNL Extension, Natural Resource Districts, the Natural Resource Conservation Service, crop consultants and other interested partners that will enable the adoption of water and energy efficiency measures. Collaborating to maximize the net benefits of irrigated crop production is of growing importance in Nebraska because many areas in the state are involved in significant management changes to conserve irrigation water.

History and goals of demonstration projects

NAWMN formed in partnership with the UNL Extension and the Upper Big Blue Natural Resources District from an interdisciplinary group in early 2005 involving growers from south central Nebraska. The state Natural Resources Conservation District (NRCS) became a valuable partner in this Network in 2006. The demonstration projects started in the Upper Big Blue NRD and have been extended to other parts of the state in 2007.

The main goal of the Network is to enable transfer of high quality information to Nebraskans through a series of demonstration projects established in farmers' fields, and to implement newer tools and technologies to enhance crop water use efficiency and energy savings. We believe that this interdisciplinary demonstration project will:

  • help to increase the adoption of appropriate newer technologies and methods to obtain higher crop water use efficiency on a field scale;
  • enable and enhance communication and information exchange between farmers, academics, NRCS, UNL Extension, NRDs, and other state and federal agencies.
  • The Network will promote water conservation.

The Network is working hand-in-hand with growers and crop consultants on strategies on how to achieve efficiency through a series of field demonstrations, initiated in the Upper Big Blue NRD in south central Nebraska. The NAWMN is supported by Dr. Suat Irmak's extensive field research projects, including research on the accuracy, durability and other operational characteristics of ET-based tools, watermark sensors, frequency-domain reflectometry, time-domain reflectometry, capacitance type, and other soil moisture sensor technologies since 2004.

ET Gage Sites map

Example: The Upper Big Blue NRD has a million acres of irrigated cropland, which is the largest of all of the NRDs in the state. With over 12,000 irrigation wells, saving one inch of irrigation water in this area would reduce pumping of groundwater by 27.1 billion gallons (3.6x109 ft3). With current diesel fuel prices, this would result in about 5 million dollars of savings in energy cost due to reduced pumping in this district alone.

Initial progress and accomplishments

In the first year of the NAWMDN (2005), 20 growers joined the Network as collaborators. As a first step, field demonstration sites were established in growers' fields in that year in the month of May (See Figure 1 at right: ETgage® and Watermark sensors demonstration sites in the growers fields in south central Nebraska in 2005 and 2006.)


ET corn sensors photoField demonstration procedures and initial results:

  1. One ETgage and four Watermark sensors were installed in each field (at 12, 24 and 36 inches up to 4 ft deep in the soil profile).
  2. An important aspect of the project was to ensure that on-site, one-to-one instruction with each grower was provided. Growers were shown how to use the ETgage to collect and interpret the data for irrigation management.
  3. Varying length of pipe was cut to ensure consistent depth placement.
  4. As sensors were installed, soil samples for analysis of texture and organic matter content were also taken.
  5. Modified Atmometers (ETgages) were installed at different locations in and around corn and soybean fields to monitor crop water use and determine the location effect on ETgage performance.
  6. Some of the ETgage and Watermark sensors were read by the growers and some by the Network core group members on a weekly basis.
  7. The NAWMDN team organized several meetings during the growing season to implement the project, review the results, assess the progress made, set future goals, and obtain feedback from the growers on the demonstrations.

The first year results and collaborations with growers yielded excellent outputs. Another significant outcome of 2005 demonstrations was a significant increase in grower interest in joining the NAWMDN. In 2006 the network grew to over 60 collaborators with an increase to over 120 producers in 22 counties and 9 NRDs in 2007.

Feedback reported:

  • Some growers reported between 2 to 3 inches of irrigation water reduction when they used the ETgage and Watermark sensors to make irrigation management decisions.
  • The first year exposed growers to the Watermark sensors and the ETgage for monitoring soil water status and crop water use.
  • Surveys from 2006 and 2007 indicate growers benefited from water savings starting at .5" to an average 1.0-3.0" as a result of using the ET gages and Watermark sensors to make irrigation management decisions.

Cost Sharing:
Several NRDs provide cost share funds for interested cooperators. The Upper Big Blue NRD is currently cost sharing 50% of the ETgage and Watermark sensors for growers in their district. In the cost share program, growers are required to report their weekly crop water data back to the Network to be posted on the website. Collaborators report their weekly crop water use and crop growth stage to the Network and the information for all demonstration sites is posted on the Upper Big Blue NRD Web site and other sites listed below. The user can click on each numbered location (a demonstration site) to view the weekly crop water use for corn or soybeans. The main objective of posting the crop water use data on the Web page is to share the information with the other growers, crop consultants, and other users. As a result of these first examples, other NRD's are now also providing cost share to their producers. The Little Blue NRD and Central NE Public Power and Irrigation District post reported water usage on their Web sites.

Table 1. An example of weekly crop water use, crop coefficient, and crop growth stage information for one demonstration site in the Nebraska Agricultural Water Management Demonstration Network (NAWMDN) as it appears on the Upper Big Blue NRD Web page.

Tools and Sensors Used:

Modified atmometer in corn fieldAn Atmometer (ETgage) is one of the alternative tools that can be used to mimic ET rates and subsequently this information can be utilized for irrigation management. The simplicity of use and interpretation of the ETgage data, as well as the economic feasibility, make it easy for farmers to monitor their own crop water use and irrigation practices.

The success of this project is dependent upon the type of existing and/or newer technologies. Tools selected must be accurate but easy to understand and operate; the data gathered from these tools should not be difficult to interpret.

For this reason, Atmometers (ETgage, at right) were used to monitor crop water use in the NAWMDN. For more information on the Atmometers (ETgage) see the UNL Extension NebGuide G05-1579, Modified Atmometers (ETgage) for Irrigation Management.  For more information on the Watermark sensors see the UNL Extension circular EC783 Watermark Granular Matrix Sensor to Measure Soil Matric Potential for Irrigation Management (PDF 8pgs, 530KB).

The Network will research and demonstrate other new tools or sensors as they become available.

Contact Information for the NAWMN

Growers, crop consultants, state and federal water regulatory agencies and other interested partners can contact one of the members of the Network if they would like to sign up and be a part of the project and efforts. Contact Us

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