UACES Facebook Arkansas Irrigation - Agriculture | PHAUCET software, Online Scheduler
skip to main content

Irrigation for Agriculture in Arkansas

 

Computerized Hole-Selection

Computerized Hole Selection (CHS) is a computer software application which designs and evaluates furrow irrigation systems. CHS uses pipe friction loss, pipe elevations and flow rate, and pressure to calculate punched hole sizes in layflat tubing (flexible poly-pipe) for uniform application of water, even in systems with varying row lengths.  Down-row uniformity means rows are watered evenly, reducing tail water, improving irrigation efficiency and conserving water and energy.  Use of CHS has the potential to reduce water usage and irrigation cost by 25% or more in most cases.

The PHAUCET (Pipe Hole and Universal Crown Evaluation Tool) is a free GNU General Public License (GPL) computer software application.  It was designed by engineers with the National Resources Conservation Service (NRCS) in Missouri to calculate existing irrigation system performance and define alternatives for improving irrigation efficiency. 

PHAUCET assists farmers determine the sizes of the holes in the layflat flexible poly-pipe that best distribute the available water. The program also helps farmers improve timeliness of watering fields having different row lengths.

PHAUCET 2012 version 8.2.20 (self-extracting; 8.7MB)

PHAUCET installation "Read Me" file

 

PHAUCET Training Materials and Design Examples

Source Title
PHAUCET (Pipe Hole and Universal Crown Evaluation Tool) | Arkansas Extension PHAUCET User Manual with Design Examples
updated by Arkansas Extension (1.5MB; 56 pages)
PHAUCET (Pipe Hole and Universal Crown Evaluation Tool) | Arkansas Extension PHAUCET Entry Sheet for Poly-Pipe
Producer form to return to County Extension Agent for hole-punching instructions | Arkansas Extension
PHAUCET (Pipe Hole and Universal Crown Evaluation Tool) | Arkansas Extension PHAUCET Quick Start Instructions
by Mike Hamilton, Poinsett County Extension Agent | Arkansas Extension
PHAUCET (Pipe Hole and Universal Crown Evaluation Tool) | Arkansas Extension Tips for Conserving Irrigation Water in the Southern Region
Irrigating Smart fact sheet (3241-K)
PHAUCET (Pipe Hole and Universal Crown Evaluation Tool) | Yazoo Mississippi (YMD) Delta Joint Water Management District PHAUCET Design Examples
slideshows by Yazoo Mississippi Delta (YMD) Joint Water Management District
PHAUCET (Pipe Hole and Universal Crown Evaluation Tool) | Water Resources Research Institute | Mississippi State University LIDAR Data for Furrow Irrigation System Design in the PHAUCET Program
presentation by Shane Powers (YMD Joint Management Water District) at the Mississippi Water Resources Conference; Jackson, Mississippi.
Texas A&M AgriLife Extension Service Using Flexible Pipe (poly-pipe) with Surface Irrigation (L-5469)
fact sheet by Texas A&M AgriLife Extension Service

 

Delta Plastics' Pipe Planner is a subscription-only Web-based application designed to help create the most efficient irrigation system for row crops.  Pipe Planner features include:

  • Store all your information on the Delta Plastics secure server
  • Access your data at any time
  • Easily maintain and upgrade your plans as needed
  • Access real-time support services

To learn more about Pipe Planner offerings and pricing, contact a Delta Plastics representative at 800-277-9172 or at http://www.pipeplanner.com/

Disclaimer:  Links to external commercial websites are provided for convenience and information only.  Inclusion of websites does not imply approval of the commercial product or service by the University of Arkansas' Division of Agriculture to the exclusion of other products or services that may be similar.

The mention of any commercial product or service in this website does not imply endorsement by the University of Arkansas' Division of Agriculture over other products or services not named, nor does the omission imply that other products or services are not satisfactory.

The University of Arkansas' Division of Agriculture does not guarantee the standard or accuracy of information on external websites, or its accessibility for people with disabilities.

 << BACK TO TOP

Irrigation Scheduling

The goal in irrigation scheduling is to determine the timing of irrigation, the duration of irrigation, and the amounts of water applied based upon crop needs, soil water storage capacity and climatic conditions, all leading to efficient water use. [courtesy of Agricultural Water Conservation Clearinghouse]

 

Soil Moisture Sensors

Soil Moisture Sensors are a tool that is useful to directly assess the crop water balance.  There are many different types of soil moisture sensors, but most commercial sensors used for agricultural irrigation fall into three categories, total domain reflectometry, capacitance or dielectric sensors, and soil matric potential sensors.  TDR sensors typically use produing wires or probes and measure soil moisture by measuring the time difference of a signal passed along the probe, the water content changes the time it takes the wave to travel the probe, this delay is directly proportional to the volumetric soil water content. Capacitance probes sense the water molecules in the soil which have a dielectric property (soil has no dielectric response), and this is related to volumetric soil water content.  Soil Matric Potential Sensors, the most common is a WatermarkTM, measure the matric potential or tension.  Tension is a measure of the energy that a plant exerts to extract water from the soil, typically measured in centibars.

Factsheet on How to Make a WaterMark Sensor

Factsheet on How to use Watermark Sensors for Scheduling Irrigation

Factsheet on how to Predict the Last Irrigation of the Season using Watermark Soil Moisture Sensors


 

Scheduling Irrigation Using an Atmometer with Chris Henry | YouTube ARextension channel | Arkansas ExtensionScheduling Irrigation Using an Atmometer with Chris Henry

Atmometers are simple to setup and require minimal upkeep.  They should be placed adjacent to crop fields, and mounted at least 39 inches high and above the crop canopy, to provide accurate on-site evapotranspiration (ET) information.

At the beginning of the growing season, the atmometer reservoir should be filled with distilled water, and will likely need to be refilled once during the season.  The paper wafer, which prevents rainwater from entering the atmometer, should be replaced annually.

Setting the Atmometer

The following sheets have been developed to help Arkansas producers set their atmometers and may not be appropriate for use outside the region.  Currently, a chart has not been developed for rice.

ET Gauge Sheet - Corn

ET Gauge Sheet - Soybean


The decision process of determining when to irrigate crops is referred to as irrigation scheduling.  There are several different irrigation scheduling methods available to producers who irrigate.  Most of these methods have been evaluated in Research and Extension studies by the University of Arkansas System's Division of Agriculture.  The water balance approach to irrigation scheduling has been determined to be the most practical and suitable method for Arkansas producers.  This approach is also used by producers in Mississippi, Louisiana, Tennessee and Missouri.

The Arkansas Irrigation Scheduling website can be used for corn, cotton, grain sorghum and soybean crops that are irrigated with furrow, center pivot, border or levee irrigation methods.

Arkansas Online Irrigation Scheduler

 

<< BACK TO TOP

Irrigation Methods


Center pivots offer the ability to irrigate fields that have surface slopes that make it impossible or impractical to irrigate with surface methods. They also offer more water management options than surface irrigation. The need for good surface drainage still exists with pivot irrigation and should not be overlooked.

Pivots are best suited for large square-, rectangular- or circular-shaped fields free of obstacles such as trees, fences, roads, power poles, etc. Field ditches are also a concern if the pivot towers must be able to cross them. Pivots can cover a range of acreage depending on the allowable length, but the common 1/4-mile system will cover approximately 130 acres of a 160-acre square field. It is also possible to tow a pivot from one field to another. It is usually best for a system not to be towed between more than two points during the season.

The biggest challenge with center pivots is the initial cost. However, it does offer some advantages that can justify the initial cost, especially when surface irrigation is not possible and the cost is spread over an expected service life of at least 15 years.

 

Center Pivot Irrigation Resources

 


The concept of border irrigation is to flush a large volume of water over a relatively flat field surface in a short period of time. Borders are raised beds or levees constructed in the direction of the field's slope. The idea is to release water into the area between the borders at the high end of the field. The borders guide the water down the slope as a shallow sheet that spreads out uniformly between the borders. Most of the border irrigation in Arkansas has been used for soybean irrigation.

Border irrigation is best suited for precision graded fields that have slope in only one direction.

The crop should be flat planted in the direction of the field slope or possibly at a slight angle to the slope. Planting across the slope tends to restrict the water flow, especially on fields with less than 0.1 ft. fall per 100 feet. Fields with slope in two directions are not as well suited to border irrigation, but it may still be possible if the borders spacing is relatively narrow.

Border irrigation will not work on all fields and is not necessarily a better method where the crop is already grown on good beds and furrow irrigated. However, if a grower wants to move toward flat planting and reduced tillage on these fields, then border irrigation may be more appealing than flood.

Border Irrigation Resources

 


Surge Irrigation | Arkansas ExtensionFurrow irrigation can be a very effective irrigation method.  One of the biggest requirements for furrow irrigation is that the field must have a positive and continuous row grade.  This usually requires precision land grading, which can be rather expensive.  However, the grading results in positive field drainage that greatly enhances production.  The row grade should be a minimum of 0.1 percent and no more than 0.5 percent; row grades between 0.15 and 0.3 percent are especially desirable.

Furrow irrigation by necessity requires that there be some amount of tail water runoff from the end of the rows.  All the middles will not water out at the same rate, especially those that are wheel middles.  Also, cracking soils can make furrow irrigation management more challenging.  However, irrigating on the appropriate schedule will reduce the problems associated with too much cracking.

Surge Irrigation

Surge Irrigation | Arkansas Extension"Surge irrigation is a combination of computerized and mechanized methods used to improve the uniformity of water entering the soil down a row in a furrow irrigation system.  Water is introduced to one area of the irrigated field for a certain or period of time duration, then switched to a different irrigated area, then returned to the original area.  Surge valves automatically switch the irrigation water between lateral lines, on a timed sequence.  Switching back and forth is continued until the entire length of the furrow is watered."

"By pulsing, or surging, the water advances down the furrow faster than it would with the constant flow in a conventional furrow irrigation system, thus improving the uniformity of application of water throughout each irrigated furrow.  By decreasing the time needed to advance to the end of the furrow, deep percolation is reduced.  This is particularly true in coarse-textured soils.  Irrigators have reported the surge systems averaged between 20 percent and 30 percent reduction in water use per irrigation, depending on soil type and system flow rate."

[definition courtesy of Agricultural Water Conservation Clearinghouse]
  Surge Valve Installation

Mississippi County Extension agent, Ray Benson, talks about surge valves and how to install them.

Watch the video
  Surge Valve Profile

This animation demonstrates how a surge valve can be used to improve furrow irrigation efficiency.

Watch the video

Furrow & Surge Irrigation Resources

 


Flood irrigation with levees should really be thought of as flush irrigation. The challenge is to get the water across the field as quickly as possible. It is also important that irrigation is started before the crop experiences drought. If plants are drought stressed and then subjected to an extended wet soil condition, plant development can be delayed and some plants may die.

Levees are often broken in several places or completely knocked down to get the water into the next bay. Rebuilding the levee in time for the next irrigation is often difficult because the levee area tends to stay wet. Some growers install gates or spills in the levees to avoid irrigation delays due to rebuilding the levees between irrigations. When possible, it is recommended that gates or spills are also installed in the outside levee. This provides better drainage of a field in a situation where a rain occurs during or soon after the irrigation.

It is recommended that water not be allowed to stand on any area for longer than two days. This can be difficult on big, flat fields. Some growers are able to divide these type fields into two smaller fields when they start irrigating so they can better manage the water. If this isn't practical, then providing multiple water inlets to the field can be helpful. Multiple inlets help avoid running water too long at the top of the field in order to get water to the bottom of the field. One multiple inlet method is to water the upper half of the field from the pump discharge or riser and then run irrigation pipe or tubing from the discharge down the field to water the lower half. A canal or flume ditch alongside the field can also be used for multiple inlets. The water can be directed from the ditch through cuts or spills into individual bays down the length of the field.

Levee Irrigation Resources

 

<< CLOSE


Irrigation Methods - Subsurface Drip Irrigation (SDI) between cotton rows | Water Conservation | Environment & Nature | Arkansas Extension
Subsurface drip irrigation tube installed between the rows of cotton [Photo courtesy of Cotton, Inc.]

Subsurface drip irrigation (SDI) is one of several types of micro-irrigation.  It is defined as "efficiently applying water directly to the root zone of plants by means of applicators operated under low pressure and placed below the surface of the ground."

"Water drips from openings (emitters) located at regular intervals along the pipe.  The pipe/tubing may be porous to allow further water seepage.  Less water is used in drip irrigation than with conventional methods."

[definition courtesy of Glossary of Agricultural Production, Programs and Policy]

Subsurface Drip Irrigation (SDI) Resources

 

<< BACK TO TOP

Irrigating Smart: Pumping Plant Efficiency Series

Most agricultural producers are using older diesel power units and old wells where upgrading to newer wells and diesel or electric motors need to be technically and economically evaluated.  As the price of gasoline and diesel fuel rises, the cost of irrigating crops in Arkansas dramatically increases.

Irrigators need a mechanism by which to evaluate the state of their pumping systems. With the current high diesel cost, this information is crucial in determining the profitability of switching to an electric motor or rebuilding existing diesel power plants. Additionally, producers need such analyses when applying for federal grant funds from the Resource Conservation & Development Councils (RC&D) or Natural Resources Conservation Service (NRCS) to assist them with electrical infrastructure or well replacements, respectively.

How is pumping efficiency determined?

A pumping system’s efficiency is calculated by comparing the amount of fuel used with the amount of water pumped. This efficiency will change due to the depth of water being pulled from a well, the condition of an engine and the rate at which the motor is turning. The calculated performance is then compared with the performance of the motor under perfect, laboratory standards. Typically, electric pumping systems will have a 75-85% overall efficiency, and diesel-powered pumps will have between 18-35% efficiency, depending on the age and care of the engine.

To calculate a system’s pumping efficiency, several pieces of information are needed. If this information is not able to be collected, assumptions can be made to estimate the efficiency. However, great care needs to be taken to make appropriate assumptions to prevent a gross over- or underestimation of the system’s performance.

Irrigating Smart conserves water, saves money and reduces energy.  The Irrigation Pumping Plant Efficiency Series was developed by the LSU AgCenter, Texas A&M University, University of Arkansas System's Division of Agriculture and New Mexico State University.

3241-A Understanding Water Horsepower | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionA brief explanation of the origin of the horsepower unit and how it relates to the power ratings of modern irrigation pumps – along with information about water horsepower, pump horsepower and pump efficiency.

Blair Stringam, Extension Plant Sciences, New Mexico State University

Understanding Water Horsepower 3241-A

3241-B Variable Frequency Drives (VFD) | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionA variable frequency drive, known as a VFD, is an electronic drive system used to control electric motors. Its purpose is varying motor speed by controlling input frequency and voltage.

Christopher G. Henry, Biological and Agricultural Engineering, University of Arkansas
Blair Stringam, Extension Plant Sciences, New Mexico State University

Variable Frequency Drives 3241-B

3241-C Soft Starters for Electric Motors | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionA brief explanation of Electrical Motor Soft Starters.

Blair Stringam, Department of Extension Plant Sciences, New Mexico State University

Soft Starters for Electric Motors 3241-C

3241-D Determining the Cost of Electricity of a Natural Gas Generator | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionInfrastructure costs associated with delivering necessary electrical power from the grid often make this conversion to properly sized, efficient pumping plants an economic compromise. An alternative method for electrical power delivery in these scenarios is the installation of an on-site natural gas generator that can power multiple smaller electrical pumping plants.

Nicholas Kenny, Extension Irrigation Specialist, Texas A&M University

Determining the Cost of Electricity of a Natural Gas Generator 3241-D

3241-E Measuring Natural Gas at an Irrigation Pumping Plant | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionAccurately measuring natural gas consumption at an irrigation pumping plant is a vital aspect of evaluating engine and pumping plant performance. Unfortunately, determining natural gas consumption usually is not as simple as reading a natural gas meter. This document will provide basic information about, as well as methods of, measuring natural gas from a common natural gas meter.

Nicholas Kenny, Extension Irrigation Specialist, Texas A&M University

Measuring Natural Gas at an Irrigation Pumping Plant 3241-E

3241-F Basics of On-site Pumping Plant Evaluations | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionA pumping plant evaluation is a testing method that allows for individual pumping plant components to be evaluated for efficiency to help in determining component sizing, replacement, compatibility and the associated economics.

Nicholas Kenny, Extension Irrigation Specialist, Texas A&M University

Basics of On-site Pumping Plant Evaluations 3241-F

3241-G Diesel and Natural Gas Dual Fuel | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionIn recent years, personal and private demand for diesel fuel has increased and diesel fuel prices have steadily risen to that of a premium fuel. This evolution has had a dramatic effect on irrigation pumping costs, to the point where many farms cannot economically continue to pump irrigation water using diesel fuel.

Nicholas Kenny, Extension Irrigation Specialist, Texas A&M University

Diesel and Natural Gas Dual Fuel 3241-G

3241-H Pump Curves | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionThe best pump performance occurs when the pump is correctly matched to the application. This requires knowledge of the application and the pump.

David Bankston, Food Sciences, LSU AgCenter

Pump Curves 3241-H

3241-I How to Read Electrical Meters | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionElectric utility companies bill clients in kilowatt-hours, abbreviated kWh. The typical American electric meter is a device that looks like a clock. The clock-like device is driven by the electricity that moves through it.

Christopher G. Henry, Biological and Agricultural Engineering, University of Arkansas
Blair Stringam, Extension Plant Sciences, New Mexico State University

How to Read Electrical Meters 3241-I

3241-J Pump Efficiency | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionThis publication includes a definition of pump horsepower, an explanation of pump efficiency and information about how to calculate those values.

Blair Stringam, Extension Plant Sciences, New Mexico State University

Pump Efficiency 3241-J

3241-K Tips for Conserving Irrigation Water in the Southern Region | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionThese irrigation management tips are designed to promote applying the water needed by the crop uniformly and efficiently while minimizing surface runoff. Combine these tips with local crop agronomic practices for a systematic approach to water conservation.

Christopher G. Henry, Biological and Agricultural Engineering, University of Arkansas
Joseph H. Massey, Plant and Soil Sciences, Mississippi State University
Horace C. Pringle, Irrigation Research Engineer, Mississippi State University
L. Jason Krutz, Extension Irrigation Specialist, Mississippi State University
Blair Stringam, Extension Plant Sciences, New Mexico State University

Tips for Conserving Irrigation Water in the Southern Region 3241-K

3241-L Measuring Irrigation Flow | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionMeasuring irrigation flow contributes to better management and scheduling of irrigation events, thus improving profitability.

Ron E. Sheffield, Biological and Agricultural Engineering, LSU AgCenter
Christopher G. Henry, Biological and Agricultural Engineering, University of Arkansas
David Bankston, Food Sciences, LSU AgCenter
William A. Hadden, Extension Specialist (retired), LSU AgCenter

Measuring Irrigation Flow 3241-L

3241-M Irrigation Pumping Plant Safety | Irrigating Smart: Pumping Plant Efficiency Series | Arkansas ExtensionAgricultural irrigation systems move large quantities of water over short periods of time, consuming and creating a significant amount of energy in the process. So these systems require caution during operation and service.

Christopher G. Henry, Biological and Agricultural Engineering, University of Arkansas
Ron E. Sheffield, Biological and Agricultural Engineering, LSU AgCenter
Nicholas Kenny, Biological and Agricultural Engineering, Texas A&M University

Irrigation Pumping Plant Safety 3241-M

 

Additional Extension Resources

 

 


Top