SPRINKLER VERSUS DRIP IRRIGATION
With Melbourne water restrictions lifted and permanent water use rules in place, households can make the decision of having a sprinkler (spray) irrigation system or a drip irrigation system on their property.
During the long drought sprinklers were banned altogether for Gardens as well as lawns.
If people wanted to have an irrigation system they were only allowed to have a drip system on their garden and were not allowed to water their lawns at all from mains water. Now they can have a sprinkler system on their garden as well as their lawn. (Subject to current water rules)
In the years of the long drought Smart Water Shop and Wave Irrigation have converted many sprinkler irrigations systems over to drip as well as helping the DIY customer to do it themselves.
Two things happened in the 2011/2012 summer that have lead many people to either put in a new irrigation system, fix their existing system or convert back to their sprinkler irrigation systems. The first was the lifting of the water restrictions in December 2011 and second was the dry summer we were expecting.
We can’t quote you the number of people that walked into our stores over that summer with damaged sprinkler heads in their hand but I can say it was extraordinarily high.
The storey they told were similar “we mowed the top off it years ago and didn’t bother fixing it until now”
WHAT ARE THE DIFFERENCES BETWEEN SPRINKLER AND DRIP IRRIGATION SYSTEMS?
Above ground sprinklers, whether pop up or fixed head, distribute either a jet of water along with spray or a fixed arc of spray over an area of garden or lawn. For the vast majority of people with a sprinkler system, they ran off mains water and were broken down into small zones around the property. Some of the reasons for zoning the system were: water pressure not being sufficient to run the whole system at the same time and some zones having different watering requirements than others.
It had always been recognised that there were many inefficiencies in the spray system of watering and the drip system had always been a less popular option. It’s only since the drought and the water restrictions that drip irrigation has risen to dominance.
Some of the problems often associated with the spray system are:
- Wind drift
- Water runoff onto paths and roads
- Easily broken
- Many areas were watered that didn’t need as much water as other parts of the same zone and.
- Easily vandalised, particularly in public areas
THE DRIP SYSTEM, WHILST NOT PERFECT, DID OVERCOME MOST OF THESE INEFFICIENCIES OF THE SPRAY SYSTEM AND INTRODUCED SOME EFFICIENCIES NOT MENTIONED ABOVE. FOR EXAMPLE:
- Reduces evaporation due to the drip line being under the mulch (ideally)
- Reduces weed growth by not putting water in areas not requiring water
- Totally eliminates the wind drift issue
- Avoids run off because the water is emitted so slowly that it has a chance to soak into the soil rather than pool and run off
- More efficient for the same reason when irrigating sloped areas
- Eliminates the overspray problem because there is no spray
- Reduces water consumption when designed correctly and the right run times are programmed.
- Delivers water directly to the root area of the plant where it’s needed the most
- Reduced vandalism because it’s out of site
Under level 2 water restrictions you were allowed to irrigate your garden using drip irrigation methods but only in your allocated times and days of the week.
For those with other sources of water, special drip lines could be used to irrigate lawn areas (as long as you install them before the lawn is laid) by running drip lines under the ground and at a depth that efficiently provides water to the roots.
One of the arguments against inline drip systems is that the emitter holes are spread evenly along the hose and many people run the dripper hose from one part of the garden to the next over areas that don’t need water.
Another is that you can’t see whether the drippers are working or not like you can with sprinklers.
Many people tell us that they just like seeing water spraying in their garden.
However, there are ways around these problems: firstly instead of installing inline dripper tube, use Low Density Polyethylene (LD Poly) hose and have individual drippers only at each plant or have Miniscape (which is a 6mm inline drip tube) coming off the LD Poly at the point closest to the plants.
You should also schedule an annual check of your drip system to ensure every part is working correctly.
As dripper systems don’t need nor can be run on the high water pressure of the mains, pressure reducers are used to reduce the mains pressure down from the 600Kpa to 800Kpa range to the 180Kpa to 300Kpa range.
Other components of the drip system include the air release valve, which is used at the highest point of each zone in order to prevent a vacuum occurring when the water is turned off in the zone and water flowing out of the lowest positioned drippers.
There’s the flush valve, which is normally placed at the lowest or end point of the zone to flush out any impurities that have found their way into the tubes and there is the filter which does the job of reducing impurities getting into the system in the first place.
Some dripper hose layouts are shown in the diagram to the left.
NEW WATER EFFICIENT SPRINKLER NOZZLES
In recent times, irrigation component manufacturers have introduced more efficient watering nozzles that are fitted to the top of pop ups and risers that use up to 30% less water and provide lower precipitation rates thus reducing many of the pitfalls of the traditional spray heads.
Click on the Hunter Logo below to view the range of Hunter MP Rotator water efficient nozzles.
PLANNING YOUR IRRIGATION SYSTEM
Our suggestion is that you let us help you.
The first option is to have Smart Water Installations (A division of Smart Water Corporation) come and provide you with a quotation on designing and installing an irrigation system for your property, be it your home or commercial property.
Whether it be a new system (sprinkler or drip) or converting an existing system to a drip system or visa versa, we can provide you with an obligation free quotation to do the work for you.
Just call us on 03 9754 0900 or drop in at one of our stores to have a preliminary discussion about your needs.
The second option is to do it yourself. It's not that difficult!
With our assistance in planning your project, understanding the components required, tips and ideas as well as the pitfalls to avoid, we can help you to achieve an efficient irrigation system.
Please click on the following link to our free Irrigation Planner.