Project: Washington State Irrigation Project State: Washington Pipe Type: CW FRP Length (ft): 10, 794 Diameter: 47" Pressure (PN): 6 PSI: 16 Installation Type: Open Cut Use: High Pressure Irrigation
USA’s Washington State is one of the most fertile food-producing areas in the world. But with low rainfall, the state’s agricultural boom is dependent on irrigation systems to feed its crops. IRZ Consulting and Engineering and Infrastructure Solutions International recently supplied a major food producer in the area with an energy-efficient fiberglass-reinforced plastic (FRP) irrigation solution that provided significant cost savings to their clients.
Washington State’s booming agricultural industry and the importance of irrigation systems
The rich sandy loam soil of Washington State makes it one of the most productive areas in the world, with large commercial farms that feed populations globally. The volcanic soils of the region and a long growing season means that the area produces large amounts of fruits and vegetables, including potatoes, corn, peas, carrots, apples, peaches, cherries, wheat, alfalfa, onions and more.
But the area doesn’t get a lot of rainfall, sometimes receiving less than 10 inches of moisture each year, making irrigation systems integral to the farms’ ability to produce a reliable and sustainable supply of food.
Local contractor, IRZ Consulting and Engineering has been providing turnkey mechanized irrigation solutions to farms in the area for over 35 years. In 2011, the company was purchased by global mechanized irrigation provider Lindsay Corporation and has since completed irrigation projects all over the world.
IRZ President Fred Ziari says “The average irrigation farm size in Washington State is 5,000 acres, but we have a lot that are 10,000 or more acres per farm. So we have very large-scale commercial farming, and the area is very advanced as far as irrigation is concerned.”
He explains that mechanized, center pivot irrigation systems supply approximately 1.8 million acres of farming land in Washington State.
Fiberglass-reinforced plastic vs steel pipe: selecting the right material
In 2019, IRZ was contracted by a corporate farm to install large diameter, high-pressure irrigation pipeline systems to pump water from the Snake River to prime farmland.
Water security and efficiency of irrigation systems are one of the most commonly reported material management issues for commercial farmers, so the irrigation solutions provided needed to be reliable, efficient and sustainable.
IRZ launched a competitive bid process to find a pipe supplier. Both steel and fiberglass-reinforced plastic (FRP) pipe solutions were proposed as part of the tender process, and both types of pipe presented pros and cons.
Steel pipe is locally made and has commonly been used in the region for high-pressure irrigation projects.
Ziari says “We have completed over 2,000 irrigation system designs all over the world, from Africa to Australia and New Zealand, to all over the United States and western Europe. Traditionally, for large diameter pipe projects, we’ve used steel pipe, or large PVC or HDPE pipe.
“But we started looking at FRP when we were completing a project in Sudan about six years ago. There, we used FRP with great results.”
When Ziari reviewed the bids for pipe supply for the Washington State projects, he found that FRP pipe had two main advantages over steel pipe for the project.
The first was a big price advantage, which in some cases came to around 30 per cent cheaper than alternative pipe materials.
Ziari explains that the cost of installing FRP pipe is much lower than steel because no welding is required during the construction process. Instead, FRP pipe has gasketed, ‘push-to-fit’ joints.
“It is a lot easier to install compared to steel pipe because welding isn’t required, and when you are dealing with large diameters, welding can be difficult. With FRP, it is mainly gasketed, so it is joined together like PVC pipe.”
“The cost savings for us came to millions of dollars compared to steel pipe. When you go to a large scale project, up to 1.2 meter diameter or more, it becomes very expensive. The installation is expensive and the pipe material is expensive,” says Ziari.
But Ziari notes that FRP pipe must be handled with care.
“You have to make sure it is bedded the right way, and it needs to be installed and handled much more carefully than when you are dealing with steel pipe.”
Once installed properly, FRP’s overall lifetime cost is also cheaper than steel pipelines as it doesn’t require costly cathodic protection systems to protect the pipe from corrosion – translating to a longer design life of up to 100 years.
Ziari says that the second advantage was the energy-efficient properties of the FRP pipe.
Ziari says “It is very energy efficient because the inner pipe wall is smooth, so there isn’t as much friction loss as with steel pipe. Most people are familiar with PVC pipe – FRP is like PVC but can handle higher pressures, which is what we required for these projects. You can use FRP with any pressure class basically. This gave it a big advantage over other types of pipe.
“The fact that we were able to install it economically, and it is energy efficient during operation, was very important to our clients.”
A project with a truly international scope
FRP pipe was sourced from Infrastructure Solutions International (ISI), an Australian-based company with dedicated personnel focussed on supplying materials for major construction projects.
In Melbourne, ISI’s Andy Holman sourced pipe to meet the projects’ needs, which came from the Middle East and was then shipped to Washington State.
The pipe supply timeline happened in the middle of the coronavirus pandemic, which challenged supply chains worldwide.
But Ziari says that this wasn’t a problem.
“Working in between the different time zones, we collaborated very well together. Andy is a very nice person to work with…this year, we’ve had many projects where we’ve worked with Andy and chosen to use FRP.”
“We chose to work with Andy again on these projects via a competitive bid process,” Ziari says. “We selected based on price and serviceability. Andy was competitive against steel and other FRP pipe suppliers.
Following the successful delivery of FRP pipe, IRZ installed:
- 20,000 feet (5,900 m) of 48 inch (DN1200) pressure pipe to pump water from the Snake River near Burbank, Washington to diversified crops like potatoes and corn.
- 10,800 feet (3,200 m) of 48 inch (DN1200) pressure pipe to pump water from the Snake River near Burbank, Washington to diversified row crops.
An irrigation market becoming aware of FRP pipe advantages
The projects were completed in May 2020, and Ziari says that the feedback on pipeline performance from the commercial farms has been good.
“When you install irrigation pipelines, you expect there to be a few leaks, but the performance of the FRP pipe has been very good, we’ve had very few leaks. The farms have been really happy and some of them have reordered pipe and projects with us.”
Ziari says that using FRP pipe is becoming increasingly popular as farmers become more aware of the advantages of using the pipe material for irrigation systems.
“FRP pipe is going to be used a lot more in the future. At the moment, it’s something that lots of farmers are not familiar with. Based on our good experiences, we will continue to use FRP pipe for large-diameter projects, and will try to educate others on the benefits of FRP.”
Ziari’s colleague IRZ Director Wayne Downey explains that FRP “is a really cost-effective alternative to steel and PVC. The irrigation market is just now becoming aware of the benefits of FRP.”