Equestrian Arena Irrigation: Complete Guide to Horse Arena Watering in New Zealand
Updated: Sep 3
A well-designed equestrian arena irrigation system does much more than control dust.
Consistent moisture can help maintain the performance of the arena footing, reduce airborne dust and provide a more predictable riding surface for both horse and rider. For larger or high-use facilities, effective water management can be a critical part of maintaining the arena throughout the year.
But there is no single irrigation system that suits every horse arena.
A 20 × 40 m home arena has very different requirements from a 20 × 60 m competition arena or a large multi-purpose equestrian facility. The right system depends on the arena size, footing, drainage, water supply, available flow and pressure, local weather conditions and how the arena will be used.
WTS designs and supplies irrigation systems for equestrian arenas of all surface types throughout New Zealand, from private home arenas through to large equestrian facilities and specialist Ebb & Flow arenas.
Why does an equestrian arena need irrigation?
Arena footing needs the right amount of moisture to perform properly.
As an arena dries out, fine particles in the footing can become airborne, creating dust. Dry footing can also behave differently under the horse's hoof and may become less stable or consistent.
Regular, even watering helps maintain a more consistent moisture level throughout the riding surface.
The objective is not simply to put as much water as possible onto the arena.
Good arena irrigation is about applying the right amount of water, at the right rate, as evenly as possible.
An effective irrigation system should:
Provide even coverage across the riding surface
Minimise dry areas
Avoid excessive wetting
Apply water at a suitable rate for the footing
Work within the available water supply
Operate at the correct pressure
Allow watering to be adjusted for weather and seasonal conditions
Work alongside the arena's drainage system
Arena size considerations
Arena size is one of the first things to consider when planning irrigation because the size of the riding surface directly affects water requirements, sprinkler coverage, pump capacity and irrigation zoning.
There is no single arena size that suits every horse property.
The appropriate size depends on how the arena will be used, the disciplines being ridden and the space available.
What type of arena are you irrigating?
The footing and construction of the arena are just as important as its dimensions.
Sand arenas
Sand-based arenas are commonly irrigated for dust control and to help maintain consistent footing.
The characteristics of the sand, depth of footing and drainage all influence how quickly the arena dries out and how much water it requires.
A free-draining arena may require more frequent irrigation than one using a footing material that retains moisture well.
Sand and fibre arenas
Fibre or other additives can change the way an arena holds and distributes moisture.
The irrigation system therefore needs to be considered alongside the footing specification.
Applying water too quickly can result in water sitting on or moving across the surface rather than penetrating evenly through the footing.
Grass equestrian surfaces
Grass arenas have different irrigation requirements.
The objective is not simply dust suppression. Irrigation needs to support healthy turf while accounting for soil type, drainage, rainfall, evaporation and horse traffic.
For larger grass arenas and showjumping facilities, irrigation can become a substantial water-management project.
Ebb & Flow or flooded arenas
Ebb & Flow systems are fundamentally different from conventional overhead irrigation.
A network of pipes is installed beneath the arena surface. Water can be introduced into the arena profile and subsequently drained away.
This provides a much greater degree of control over moisture within the riding surface.
Ebb & Flow systems are generally most practical when incorporated into the arena during new construction because the underground pipe network forms part of the arena design.
WTS has experience designing and installing Ebb & Flow arena irrigation, including the system at Takapoto Estate in Cambridge.
Above-ground arena irrigation
For an existing arena, an above-ground irrigation system is often the most practical solution.
Sprinklers can be positioned around the perimeter of the arena and selected to provide the required coverage.
Depending on the arena size and water supply, a system may use:
Impact sprinklers
Gear-drive rotors
Pop-up sprinklers
Raised sprinklers
Multiple irrigation zones
Automatic irrigation controllers
The important consideration is not simply whether a sprinkler can "reach" the arena.
The sprinklers need to be positioned and selected to provide uniform application across the whole riding surface.
This means considering sprinkler spacing, overlap, nozzle selection, operating pressure and wind conditions.
Generally, we recommend impact-type sprinklers rather than misting for many above-ground arena applications, particularly where effective water delivery and dust suppression are required.
Impact sprinklers vs misting
Arena irrigation is about getting water onto the footing.
For outdoor arenas, impact sprinklers can be effective because they can deliver relatively large volumes of water across substantial areas.
Misting systems are a different application. Fine droplets can be more susceptible to wind drift and evaporation, which is generally not what you want when the objective is to put water into the arena footing.
The sprinkler is only one part of the system, however.
A sprinkler needs the correct:
Flow rate
Operating pressure
Nozzle
Throw radius
Spacing
Zone configuration
A sprinkler operating at the wrong pressure can produce a very different result from its published performance.
Pop-up sprinklers
Pop-up sprinklers can provide a neat and automated irrigation solution, particularly where an arena is being constructed from new.
When retracted, the sprinkler sits within a suitable housing rather than remaining exposed above the surface.
For equestrian applications, however, sprinkler selection and installation require particular care.
The installation must avoid creating a hazard for horses and riders and should be appropriate for the arena construction and footing.
Suitable protective housings, installation depth and sprinkler selection are important.
For some arena and sports turf applications, pop-up sprinklers with appropriate protective housings (sod cups) can provide a very tidy finished installation. Pop up sprinklers with sod cups can be installed in both grass and sand arenas and provide a safe footing option with their rubberised cups.
Ebb & Flow: irrigation from beneath the arena
For facilities where consistent surface conditions are particularly important, an Ebb & Flow system can provide a more sophisticated approach to water management.
Instead of relying on sprinklers above the surface, a network of pipes is installed beneath the arena.
Water is introduced into the arena profile and allowed to move through the footing. The system can then remove or redistribute water as required.
This provides much greater control over the moisture level within the arena.
Ebb & Flow systems are particularly suited to new arena construction because the underground pipework needs to be incorporated into the arena design.
WTS has designed and installed Ebb & Flow systems for equestrian facilities including the Takapoto Estate showjumping arenas in Cambridge.
Existing arena or new arena?
The stage of your project makes a big difference to the options available.
If you already have an arena
An above-ground or perimeter sprinkler system is often the simplest option.
We can assess:
Arena dimensions
Existing water supply
Pump
Pipework
Available pressure
Footing
Drainage
Sprinkler locations
The irrigation system can then be designed around the existing arena.
If you are building a new arena
You have considerably more options.
Irrigation can be incorporated into the arena construction from the beginning, including underground pipework and Ebb & Flow systems.
This is also the ideal time to consider water storage, pumping, drainage and irrigation as one complete system.
How much water does a horse arena need?
This is one of the most common questions we receive — and there isn't one universal answer.
Water requirements depend on:
Arena dimensions
Footing material
Footing depth
Drainage
Temperature
Wind
Sun exposure
Humidity
Rainfall
Frequency of use
Desired moisture level
Sprinkler application rate
A free-draining outdoor sand arena in a hot, dry and windy location may require considerably more irrigation than an arena that retains moisture well.
For this reason, arena size alone cannot be used to determine the required pump or water supply.
The irrigation system needs to be designed around the actual water demand and the hydraulic performance required to deliver it.
How do you calculate arena irrigation water requirements?
A useful starting point is the area being irrigated.
For example:
20 × 40 m = 800 m²
20 × 60 m = 1,200 m²
Once the area is known, the required application depth can be converted into a volume of water.
For example, applying 1 mm of water over 1 m² uses 1 litre of water.
Therefore:
800 m² × 1 mm = 800 litres
And:
1,200 m² × 1 mm = 1,200 litres
This does not mean that every arena should receive a particular number of millimetres of water. It simply demonstrates why arena size, application rate and water availability need to be considered together.
The actual irrigation requirement depends on the footing, weather, drainage and desired moisture condition.
Water supply is critical
Before choosing sprinklers or a pump, determine what water supply is available.
Possible sources include:
Rainwater tanks
Bores
Dams or ponds
Farm water supplies
Mains water
A combination of sources
A large tank does not necessarily mean you have a suitable irrigation supply.
For example, a 30,000-litre tank may contain plenty of water but still be unable to supply an irrigation system at the required flow without an appropriately sized pump.
Conversely, a bore may provide a good flow rate but may not provide enough instantaneous flow to run a large sprinkler system without storage.
For arena irrigation, we need to consider:
Available flow
How many litres per minute or cubic metres per hour can the water source provide?
Available pressure
What pressure is available at the irrigation system?
Pump capacity
Can the pump deliver the required flow at the required pressure?
Storage
How much water is available for irrigation?
Refill rate
How quickly is the tank, bore or other water source replenished?
Distance
How far is the water source from the arena?
Elevation
Is the arena significantly higher than the pump or water source?
These factors all affect the final system design.
Do you need a booster pump?
Sometimes the water supply is adequate but the pressure available at the arena is not.
A tank may have plenty of water but very little usable pressure. A mains supply may provide pressure but insufficient flow. A bore may require a separate pumping arrangement.
A booster pump can be used where additional pressure and/or flow is required to operate the irrigation system correctly.
However, a booster pump should not simply be selected based on the size of the arena.
The pump needs to be matched to the actual hydraulic requirements of the sprinklers, pipework, valves and water source.
This is why our DIY arena packages offer booster-pump options where appropriate, rather than assuming every property needs one.
Why pump sizing matters
A common mistake is choosing the sprinkler first and then trying to find a pump that will make it work.
The irrigation system should be designed as a complete hydraulic system.
If a group of sprinklers requires a particular flow at a particular pressure, the pump needs to deliver that performance after accounting for the losses through the system.
Pressure can be lost through:
Long pipe runs
Small-diameter pipe
Fittings
Valves
Filters
Elevation changes
Flow through the irrigation equipment
This is why a pump that appears to have plenty of pressure or flow on its specifications may not actually be suitable for the completed installation.
WTS irrigation designs use hydraulic calculations to consider flow, pressure, pipe friction losses and system demand.
How should an arena be watered?
The best watering approach depends on the footing and arena construction.
The objective is generally to introduce water into the footing rather than simply wetting the very top of the surface.
If water is applied too quickly, the surface can become excessively wet while the underlying footing remains comparatively dry.
Application rate is therefore important.
Weather also has a major influence.
Wind can increase evaporation and alter sprinkler distribution. Hot, sunny conditions can increase drying rates, while rainfall can significantly reduce irrigation requirements.
For outdoor arenas, watering during cooler and calmer periods can reduce evaporation and wind-related losses.
Automation makes arena watering easier
A manually operated irrigation system can be perfectly suitable for a small home arena.
As the arena gets larger or usage increases, automation becomes increasingly useful.
An automated system can include:
Irrigation controller
Solenoid valves
Multiple irrigation zones
Automatic watering schedules
Rain sensors
Pump control
Manual override
Automation allows watering schedules to be adjusted according to seasonal conditions and reduces the need to manually operate the system.
For a busy equestrian facility, this can make arena water management considerably easier.
Don't forget the drainage
Irrigation and drainage should always be considered together.
An arena designed to drain quickly may require a very different irrigation approach from one designed to retain moisture.
This is particularly important in New Zealand, where an arena may experience very wet winter conditions followed by hot and dry summer conditions.
An irrigation system should be considered alongside the arena's:
Base construction
Footing
Drainage
Fall
Soil conditions
Water table
Surrounding ground conditions
For a new arena, irrigation should ideally be considered during the planning and construction stage.
Common arena irrigation mistakes
1. Choosing sprinklers before checking the water supply
A sprinkler may have the required throw distance but still be unsuitable if the available water supply cannot provide the required flow and pressure.
2. Using too few sprinklers
Fewer sprinklers does not necessarily mean a cheaper or better system.
If sprinkler spacing is too wide, the arena can develop dry areas and inconsistent moisture.
3. Ignoring wind
Wind can significantly affect sprinkler distribution and evaporation.
Site conditions should be considered when selecting and positioning sprinklers.
4. Applying water too quickly
A high application rate can result in runoff or excessive surface wetting rather than allowing water to infiltrate evenly into the footing.
5. Watering only the surface
An arena can look wet without actually having sufficient moisture through the footing profile.
6. Ignoring drainage
The ability of the arena to accept and remove water needs to be considered alongside irrigation.
7. Treating the pump as a separate item
The pump, pipework, valves and sprinklers work together as one hydraulic system.
8. Forgetting future requirements
If the arena is likely to be used more heavily or expanded in the future, it can be worth allowing for this when designing the water supply and irrigation infrastructure.
Maintaining your arena irrigation system
Even a well-designed system requires maintenance.
Check sprinklers periodically for:
Blocked nozzles
Damaged nozzles
Uneven spray patterns
Leaks
Broken risers
Changes in pressure
Sprinklers that stop rotating correctly
Also check that the irrigation controller is operating correctly and that valves are opening and closing as expected.
If one sprinkler suddenly looks different from the others, don't automatically assume the sprinkler itself is the problem.
It could indicate:
A blocked nozzle
Pressure problems
A damaged valve
A pipework issue
A pump problem
Regular maintenance helps keep water distribution even and can prevent small problems from becoming larger and more expensive.
WTS can assist with all your arena irrigation servicing and repairs
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READ MORE about the WTS approach to arena irrigation and how we can help with your arena irrigtaion servicing
How WTS designs an equestrian arena irrigation system
At WTS, we don't start by asking which sprinkler you want.
We start with the arena and work backwards.
For an arena irrigation project, we consider:
This approach allows the irrigation system to be designed around the actual requirements of the property rather than simply selecting a standard collection of products.
WTS provides irrigation design using hydraulic calculations, site information and professional irrigation layouts for projects ranging from lifestyle properties to large equestrian facilities.
Equestrian arena irrigation throughout New Zealand
WTS designs, supplies, installs and maintains irrigation systems for equestrian arenas and sports turf throughout New Zealand.
Our experience includes:
Private horse arenas
Training arenas
Professional Showjumping facilities
Local riding centres
Grass arenas
Sand arenas
Sports turf
Dust suppression systems
Perimeter sprinkler systems
Automated irrigation
Ebb & Flow arena systems
Our work ranges from smaller home and lifestyle properties through to large specialist equestrian facilities.
WTS is based in Cambridge and provides equestrian and sports turf irrigation services New Zealand-wide.
Planning an equestrian arena?
The earlier irrigation is considered, the more options you have.
If you are building a new arena, talk to WTS before construction begins so that water supply, storage, pumping, drainage and irrigation can be considered together.
If you already have an arena and are struggling with dust, uneven watering or maintaining the right moisture level, we can assess your existing water supply and recommend an appropriate irrigation solution.
For smaller arenas, our upcoming DIY Arena Irrigation Packages will provide an easier way to purchase a complete system online, with water requirements and optional
booster pumps clearly specified.
WTS provides equestrian arena irrigation consultation, design, supply, installation and servicing throughout New Zealand.
CONTACT US to discuss your irrigation project
READ MORE about the WTS approach to arena irrigation and how we can help to design and install your irrigation system
SHOP ONLINE for irrigation parts, pipes and fittings
Frequently Asked Questions
How often should I water my horse arena?
There is no universal watering schedule. It depends on the footing, weather, arena construction, drainage and frequency of use.
Monitor the condition of the footing and adjust irrigation according to the conditions.
How much water does a 20 × 60 m arena need?
A 20 × 60 m arena has an area of 1,200 m². Again, the actual requirement depends on the footing and conditions.
For reference, 1 mm of water across 1,200 m² equals approximately 1,200 litres.
Can I irrigate an existing horse arena?
Yes. Existing arenas can often be fitted with perimeter or above-ground irrigation systems without rebuilding the arena.
Can irrigation be installed under a new arena?
Yes. Underground irrigation can be incorporated during new arena construction. Ebb & Flow systems use a network of pipes beneath the riding surface to provide greater control over moisture.
Can I run arena irrigation from a rainwater tank?
Yes, provided the available storage, refill rate, flow and pressure are suitable.
A pump or booster pump may be required depending on the tank and irrigation system.
Do I need a booster pump?
Not necessarily.
A booster pump may be appropriate where the available water supply has sufficient volume but insufficient pressure or flow to operate the irrigation system correctly.
The requirement should be determined from the water supply and irrigation design.
Can I use a bore for arena irrigation?
Yes. Bore water can be an excellent irrigation source where the bore provides an appropriate flow rate and water quality.
The bore yield and recovery rate need to be considered alongside the irrigation demand.
Can an arena irrigation system be automated?
Yes. Automated controllers and solenoid valves can operate multiple irrigation zones and allow watering schedules to be adjusted throughout the year.
Can you irrigate an indoor arena?
Yes. Indoor arenas have different requirements because they do not receive rainfall and may have different evaporation and ventilation conditions.
What is the best irrigation system for an equestrian arena?
There is no single system that is best for every arena.
The right solution depends on the arena surface, size, construction, water supply, drainage, budget and desired level of moisture control.
Do you sell DIY arena irrigation kits?
Yes, WTS sell DIY arena irrigation packages for common arena sizes.
The packages include clearly stated water-flow and pressure requirements, with booster pump options available where appropriate.
Can WTS design a custom arena irrigation system?
Yes.
For larger arenas, unusual water supplies, Ebb & Flow systems and projects where a standard DIY package is not suitable, WTS can provide a custom irrigation design.
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