Steve Stevens says the first time his employees heard about the new irrigation program he wanted to try on his farm they weren’t exactly thrilled at the prospect.
Stevens, who raises 4,300 acres of cotton, corn, rice and soybeans around Tillar in southeast Arkansas, decided last spring to test the “Phaucet” computer program on six fields to see if it could reduce his irrigation costs.
“When they saw how much work was involved in setting up the fields, they kind of balked at it,” he told persons attending a session on the Phaucet program at the National Conservation Systems Cotton and Rice Conference in Marksville, La.
“And I think they may have seen it as criticism of the job they were doing. But once we began using the program on more fields, and they realized they were finishing on Thursday and Friday rather than having to work Saturday and sometimes Sundays, they began to see the program in a different light.”
The employees weren’t the only ones who became sold on the program, which was developed by USDA Natural Resources Conservation Service employees in Missouri. Stevens decided to expand it from those six test fields to all 155 fields on his farm.
“We went from ‘country boy’ engineering to very precise application of water,” he said. “This program allows you to eliminate the guesswork and actually sit down and figure out the best approach to irrigating a field.”
The program, which is designed for furrow irrigation systems using flexible tubing, offers the potential for providing several types of information, says Phil Tacker, associate professor/Extension engineer with the University of Arkansas. Those include:
1. Design of holes to punch in irrigation tubing;
2. Calculation of pressure (head) changes along the tubing;
3. Adjustment of hole sizes for different row lengths in the same irrigation set;
4. Ability to evaluate different layout options for the field and irrigation tubing;
5. More uniform watering of the field in a shorter time period.
Tacker, who was a presenter along with Stevens at the conference, said the University of Arkansas Extension Service has been using the Phaucet program to help Arkansas producers irrigate their fields more efficiently.
“That has become doubly important because of the high cost of diesel fuel and the water shortages some of our growers are experiencing,” he noted.
One of the first steps Stevens took was to use a flow meter to check the output on each of the 43 wells on his farm. The output measurement helps determine the optimum speed or rpm setting for the pump on each well.
“We found we had a lot of variation in our wells,” he said. “Some of them actually weren’t working much at all.”
Stevens also used field maps from his Farm Works software to determine field dimensions and row lengths for each field. On fields where the turn row slope was known, he used a Laser unit to determine the elevation change along the turn row.
The Phaucet program allows the grower to enter a number of factors such as row length in 100-foot increments, elevations along the turn row, the distance between the holes punched in the irrigation tubing, pipe diameter, the hole diameter and the thickness of the flexible pipe.
“Once the input table is completed and a design option selected, the program produces an output data screen,” says Tacker. “The design data can be printed out in a format that can be taken to the field and used for punching the holes in the irrigation tubing.” (The program uses three different sizes of tubing for uniformity, and the operator can open more than one hole per furrow if needed.)
One piece of information from the program is the “Distribution Uniformity” value, which is an indication of how uniform the furrow water will be as it reaches the end of the field.
“The goal is for this value to be 90 or better so that the water in the furrows will reach the end at about the same time even though some furrows are longer than others,” says Tacker. “As a result, field runoff is reduced and less time will be required to irrigate the field.”
Stevens’ 4,300 acres are spread over 155 fields, ranging in size from 11 acres to 108 acres with sandy to clay soils. The fields vary from “fairly square” to rectangular to triangular shapes with furrow lengths ranging from 100 feet to 1,600 feet.
Tacker acknowledged that Stevens’ irrigation crew wasn’t excited when Stevens first began talking to them about using the irrigation program. That changed as the workers saw what the program could do.
“The irrigation crew realized that knowing the layout for the field before they got there helped them get the fields going quicker because of the reduced guesswork,” he said. “They also realized that since the fields watered more uniformly and quicker, they didn’t have to spend as much time checking them.”
Stevens and his employees did invest a considerable amount of time setting up the data sheets for each field. In addition to the time involved with gathering the field data, he averaged about 30 minutes of computer time for each field. The information is now stored on the computer for use in future seasons.
He and Tacker calculate the program helped reduce Steven’s pumping time by about 25 percent in 2008. That reduced his $4 per gallon diesel fuel cost by about $100,000 and cut the number of hours on his pumps.
“The reduced pumping also conserved about 670 million gallons of the southeast Arkansas region’s dwindling supply of ground water,” says Tacker. “That is the equivalent of 5.6 inches of water covering all of his acres, and the savings would have been greater if the August rainfall had not been well above average in 2008.”
Stevens says he was sold on the program almost as soon as he began learning how to use it, and he hasn’t changed his mind. “I wouldn’t go back to the old way of irrigating even if diesel dropped to 50 cents a gallon.”
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