Finding success in the turf industry requires having the ability to think ahead. Even as the golf season continues full bore in the northern half of North America, superintendents are preparing for the close of their golf season.One major step in the season-ending ritual involves shutting down the irrigation system and taking steps to protect it from the weather over the winter. A properly executed shutdown protects the system’s components and minimizes the risk of weather-induced damage or other issues over the winter.
Because of the acreage and the topography of a typical golf-course property, shutting down the irrigation system should be a meticulous process. Brian Vinchesi, a design engineer for Irrigation Consulting Inc. in Pepperell, Mass., stresses it’s important not to rush things. “With a golf course, it is important to go slow,” he says. “Speed gets you nowhere. (An 18-hole facility) should take two or three days to winterize.”
To complete the process efficiently and safely, it’s essential to have a written plan in place. Scott Pace is the Eastern regional manager for Rain Bird’s Golf Division He’s spent his entire career, more than two decades, dealing with irrigation issues.
“If you don’t have a good plan and do things step by step in the winter, you’re going to have problems in the spring that could be really, really bad,” he says. “You could end up with broken pipes, you could end up with broken sprinklers, you could end up with a pump station with broken pipes. It’s very, very important that you have a plan, be systematic about it and not rush in any way.”
The plan, according to Rain Bird’s Golf Technical Bulletin (11-19-01), should include an accurate drawing or drawings of the irrigation system, highlighting the location of “All ‘Zone Shut-Off’ or ‘Zone Isolation’ valves, All ‘Drain’ valves, all remote control valves, valve-in-head sprinklers, all quick coupling valves, controller locations and areas they control, etc.” Mark these locations with flags so you and your team won’t have to spend time looking for them during the actual shutdown process.
At the same time, be sure each valve is operating properly. The written shutdown plan should list the areas to be evacuated in sequence, starting with the areas farthest from the compressor and working back toward it from there.
“(Superintendents) should drain the main line if they have drain valves or use quick couples,” Vinchesi says, “and then blow the system out with compressed air. It works best if you can blow it out from the pump system location. The amount of compressed air is what is important, not pressure.”
Vinchesi recommends a minimum air volume of 160 cubic feet per minute (CFM) for an 18-hole facility, but the ideal volume will vary from course to course depending on the capacity of the irrigation system and the topography of the property. Most courses will require something in the range of 250-300 CFM range and some larger systems may require as much as 600 CFM.
It’s also essential that the air pressure in the system during the blow out not exceed what the system is designed to handle. This should be calculated by determining the maximum pressure at the weakest part of the system. This figure will be somewhere in the neighborhood of 60 pounds per square inch (PSI). During the blow out, the air pressure should be well below that figure. “Our recommendation is somewhere between 40 and 50 PSI and to not exceed that,” Pace says.
Over the course of his career, Pace has seen superintendents exceed their systems’ air-pressure specifications with calamitous results. “That’s probably one of the biggest mistakes I’ve seen over the years,” he says. “Not adjusting (the air volume) and compensating with pressure. They’ll turn the pressure up to 100 PSI and damage the system.”
The compressor should be inserted into the irrigation system at the system’s highest point. Care must be taken to dissipate the heat generated by the compressed air before it enters the system, because overly hot air will damage the components.
“(Superintendents) will make a connection with their compressor and that air is hot,” Pace says “and it heats up as it goes through the fitting. I’ve seen guys melt pipes right at the connection point so you need to figure out the best place to connect to system without doing damage caused by that heated air coming out of the compressor.”
Pace suggests using a 2- or 3-foot piece of galvanized pipe as a heat sink to absorb the heat coming off the compressor and pipe at the connection point. He notes it’s important to use a compressor that’s compatible with the irrigation system itself. If the air flow or air pressure through the system continues to generate excessive heat, he suggests using a longer piece of pipe as the heat sink.
Vinchesi says that in some cases it may be preferable to blow out the system from more than one location, depending on the topography of the property. Depending on the layout of the golf course, elevation changes especially, you may have to blow out from several places, he adds.
Pace says when blowing out from multiple sites, it’s best to start at the highest point on the property and go from there. “Typically, you would like to go from the high points to the low points on the golf course and if you have multiple high points on the golf course, you would want to connect the compressor at those locations and then work through it systematically from the low point back to the compressor when you’re turning on stations or sprinkler heads,” he adds.
Frank Tichenor is the superintendent at Forest Hill Field Club in Bloomfield, N.J., where he oversees a staff of 14 that tends to an A.W. Tillinghast design that dates back to 1926 and features an abundance of elevation changes. The club installed a Rain Bird irrigation system roughly a decade ago and Tichenor takes a systematic approach when he shuts it down each year. “I have a checklist,” he says. “We’ve got a few different things that we do when we blow out.”
In addition to having a written plan for handling the shutdown, Tichenor will make sure to order a compressor in timely fashion and have a sufficient number of fittings on hand. “It’s almost like a countdown to the day we blow the system out,” he says.
During the period prior to the actual shutdown, Tichenor and his team strive to extract as much moisture from the system as possible. “The key is to get as much water as possible out of (the system) early,” he says. “We’ve got quite a few drains out there where we can drain it in different sections. A couple days in advance, we open up the drains. We have a dedicated (2-inch) fitting for the air compressor that we put in when we put in the system.”
Although the golf course remains open through Dec. 31, Tichenor blows his system out around Halloween. “We’re not really watering anything in November,” he says. “I want to get it done before it gets real cold. It’s really kind of a pain in the neck to blow it out when it is freezing out because you get stuck heads and everything. It’s not a lot of fun if you get a stuck head and it’s 30 degrees.”
While the irrigation system may not be operational after the shutdown is completed, its components must still be protected. Like many superintendents, Tichenor keeps a heater running in his pumphouse during the winter months. “We have a heater in our pumphouse that we keep at (approximately) 40 degrees,” he says. “I just would rather keep the temperature above freezing.”
Vinchesi recommends keeping the pump system control panel powered up during the winter months. “If the pump house is not heated, some components, such as a pressure-relief valve will need to be disassembled,” he says. “Some other components, such as backflow prevention devices, may need to be heat taped for the winter if water cannot be drained out of them.”
Pace recommends leaving all stain valves open during the winter. He also advises running the system through a full cycle on a weekly basis with all sprinkler heads activating all valves. “If water settles out to a slow point, you can relieve some of the pressure,” he says. Pace also recommends superintendents continue to provide power to their satellite control boxes and weather stations during the winter months.
Vinchesi cautions against waiting too long to perform the shutdown. “Anything with water in it above ground is going to be susceptible to damage during freezing temperatures,” he says. “The in-ground equipment can wait until the soil starts to freeze, but if you wait too long, the water in the sprinklers will freeze or damage them and make your eventual blowout problematic.”
Pace emphasizes planning ahead, including ordering the right compressor far in advance and getting the task done as quickly as expeditiously as possible. He notes that some in the industry underestimate the time it takes complete a shutdown properly.
“If you rush it, you have a tendency not to get all the water out,” he says. “We recommend you shut the system down and then come back the next day to see what’s settled back and to see if there is any more water from those areas.”
Pace says that it’s literally impossible to eliminate 100 percent of the water from an irrigation system, even if the shutdown is done properly. But in the end, Pace adds that executing a proper shutdown and winterization of the irrigation system, while it may be a time-consuming process, will pay off handsomely.
“My thing is, get it winterized as early as possible that you can do it,” he says, “and leave your golf course in good condition and your irrigation system ready for next year.”