A basic drainage system was installed on the site during the 1940’s and 1950’s when Spence Field was a military airbase. Additional drain tile was installed during the late 1970’s in the early years of the farm show. Then over the next 30-years drain tile was added, replaced and repaired. Despite this, the Expo farm has long suffered from saturated soils.
The first phase of the newest drainage project took place in a small field where University of Georgia Extension weed scientist Stanley Culpepper conducts research on controlling difficult weeds such as glyphosate-resistant Palmer amaranth. A nearby second field behind the Expo farm shop will be used for drain tile demonstrations and educational seminars during the Oct. 16-18 farm show. Expo visitors will learn why and where drain tile will benefit land in the Southeast.
Expo farm manager Michael Chafin coordinated the drainage project. “Farming that land was like driving over a dry lake,” said Chafin. “You couldn’t get through it when it got wet.”
Others involved included John Burnham with Burnham Soil & Water Management, Matt Palmer with Advanced Drainage Systems (ADS) who supplied the drain tile used at Expo and Steve Dean with Trimble Navigation.
They placed the lateral lines about 40 feet apart, so the lines will drain excess water from 20 feet on each side. The lateral lines for the new drainage system feature four-inch ADS perforated plastic drain pipes. These were connected to a six-inch main line. It empties the excess water into a large capacity storm drain system installed when Spence Field was an airbase. Chafin says most of the lateral lines extend about 450 to 500 feet into the field.
Trimble, the official global positioning system provider at the Expo, is now bringing precision farming technology to drainage installation with a product called WM-Drain. The tools included in WM-Drain streamline the surveying, design, installation and mapping steps associated with drain tile. WM-Drain insures that the designed grade and soil depth will be maintained during the installation.
Burnham is based in Michigan has extensive experience with drain tile installation in the Midwest and in Florida. At Expo, he used an all terrain vehicle with rubber-tracked wheels and GPS to survey the field and to design the tile layout. “We took the tires off and put the rubber tracks on,” says Burnham. “This gives us a more accurate survey, especially in the bottoms of ruts and in the wettest areas of fields.”
Burnham collected the data and used his computer to calculate the size of the main lines and the drainage coefficients that tell how much water can be removed in a 24-hour period.
GPS speeds up the time it takes to survey a field and design the drainage system.
“GPS allows us to fine tune the designs so they are much better for the farmer,” says Burnham. GPS also allows for precise location of the tile when later repairs or maintenance are needed.
Burnham says it’s a good idea to run the lateral lines perpendicular to the direction that the crops are planted. “Larger tractors and equipment today tend to form compacted lanes,” he says. “If the laterals run in the same direction as the planting row, then the lateral lines need to be placed closer together. By running the laterals perpendicular to the row, they draw water from a wider area and work great.”
As a distributor for ADS, Palmer has exhibited at Expo during the past three years. He is also a principal in a Florida-based firm called SWAT. This stands for Soil & Water Agricultural Technology. During the past two years, SWAT has managed several large-scale turnkey irrigation and drainage projects in Florida. Burnham is also a member of Palmer’s SWAT organization. “What I do now is way more than selling tile,” says Palmer.
Palmer hopes to work with Expo on additional projects. For instance, he would like to see GPS and telemetry added to one of the Valley pivots at Expo. “We want to work with these at Expo to show the potential for increased yields,” he says.
Dean, who is based in Ohio, brought a Wolfe trenchless plow to Expo equipped with Trimble’s WM-Drain technology and used it to install the drain tile. He also used the Expo farm to test some updates to the WM-Drain system. Dean says the WM-Drain and its associated tools eliminate hand labor while placing the tile at a consistent depth and maintaining the designed slope. Properly designed and installed drain tile creates better root structure, according to Dean. “The roots reach the water and we see more uniform crop growth because we maintain the ideal water levels,” he adds.
According to Burnham and Dean, the older drain tile at Expo was not working properly because the original tile was installed too deep, most of it at depths of about five feet and below a layer of compacted soil. Most of the new tile at the farm was placed about 36 inches deep, with at least 32 inches of soil covering the lateral tile lines.
“I would like to thank Expo farm manager Michael Chafin for the opportunity to make this happen,” says Dean. “We will get the data on this project and get the word out to farmers who come to the farm show so they will see the value of tile drainage.”