18 September 2018, 12:00AM
Over time, two different types of irrigation have been recognized as superior methods — drip and centre pivots. Growers now associate certain pluses and minuses with each. Some of these assumptions are true. Some are myths. 
So how do you make a decision between the two? You compare the facts. This is the first of a series of blog posts that will address some of these misconceptions. 

Separating Fact From Fiction

There are many important factors, but here are three main things to consider: 
1. Initial Investment Cost – Pivots cost less, and retain their value.
2. Labour – One person can remotely manage numerous pivots irrigating thousands of acres.
3. Peace of Mind – Drip systems depend on water quality, consistent maintenance and other factors.

Both options offer water efficiency of 90% or more, and drip irrigation definitely has its place; it can be effective in some settings. For example, in small or irregularly shaped fields, drip is often a viable option. But in many other situations, centre pivot irrigation is more cost effective and offers growers maximum control – and greater peace of mind.
Centre pivots provide growers with peace of mind, water efficiency and maximum yields in their large fields.

Centre pivots provide growers with peace of mind, water efficiency and maximise yields in their large fields.

Of course, when it comes to centre pivots, you will never find better, more durable products and technology than those from Valley® Irrigation.

1. Initial investment costs 

When it comes to initial investment costs, centre pivots are much less expensive than drip irrigation.
On average, pivots also last longer – 25 years or longer is normal for Valley® equipment. The longevity of drip systems is improving, but that still depends on numerous factors and some “big ifs,” including error-free system management.
Plus, even after 15 years of consistent work, Valley pivots retain 50% of their resale value. Sellers of drip systems cannot say the same.

Out of sight, out of mind -- until there's a problem. The nature of drip irrigation systems makes it hard to identify and address problems, since they are buried underground.

2. Labour

Drip systems require more labour and a higher level of management to operate and maintain. Some remote technology exists, but drip irrigation management is still largely a manual process – it can take several hours to walk a field monitoring, flushing and maintaining the filters and lines. Centre pivots are a different story.

One person can remotely manage multiple machines covering thousands of acres in minutes, using today’s computerized controls. Plus, you don’t have to hire people to install and remove equipment season after season.

Labour Comparison Between Subsurface Drip Irrigation and Centre Pivots




 Daily Maintenance
Flush Filter
Flush Lines; Chlorinate
 Weekly Maintenance
 Check system pressure at various points; Monitor system flow rates  n/a
 Monthly Maintenance
 Flush lines  Grease swivel
 Annual Maintenance
 Filter; Check valves; Confirm emitter performance; Chlorinate  Check oil levels in gearboxes and centre drives


3. Peace of Mind

Drip irrigation requires more management even if everything goes correctly, which is often a very big if. Too often, sub surface drip systems are “out of sight, out of mind.” With a pivot, you have greater peace of mind.

  • Drip systems are dependent on the skill of the person doing the work and cannot be changed after installation. Centre pivot installations are comparatively simple, the system is more flexible to changing demands, and the equipment is more forgiving.
  • Centre pivots offer more advanced remote monitoring, and it is easier to address potential problems than with drip, when pipes and tape are buried under the ground. A clogged irrigation nozzle is a brief inconvenience; a clogged drip system is a large, time-consuming expense.
  • Plugging remains a persistent problem with drip irrigation, and performance is highly dependent on water quality. Using wastewater requires more – and larger – equipment.