• The most important consideration when choosing the site for your arena is the natural drainage of the site as this is going to have a great effect on the overall cost of the project.
• Try to construct the arena on slightly higher ground than surrounding land to facilitate water drainage.
• Access to the site by trucks during construction is also important (roadways must be cleared of low tree branches and any culverts or stream crossings must be able to support a 45 tonne truck and trailer unit.
• Freight can end up being a significant component of the overall cost of materials and can be reduced if the site can be accessed by truck and trailer units rather than smaller trucks.

• Making sure the drainage of the arena adequate is critical to its sucess. It doesn’t matter what you put on top, if the water has nowhere to go you are going to get pooling.
• Adequate drainage also increases the life of the surface material and will make it more enjoyable and consistent for horse and rider. 
• The amount of drainage necessary will depend on the nature of the site including the amount of rainfall, the type of soil, the geography of the site and the surrounding features. Get advice on what you will need.
• The entire site should be structured with a gentle fall (1 – 2%) or a crown with 200 - 300mm fall to the outside so that water flows off. Most contractors will use a levelling device or even a stringline to ensure that there are no low spots that will pool water.
• Some arenas, especially in areas of high rainfall, have been constructed using drainage trenches filled with porous rock (scoria or graded aggregates) and piping ("Novaflo" coil or field tiles). Geotextile barrier cloth can be used to prevent base layer and sand particles clogging up these drainage systems.
• There must be drainage around the perimeter so water draining off the arena surface can flow away.
• Care should be taken not to impede the flow of water from the arena surface when surrounding it with boards or other types of boundary.

Base Layer:

• The arena consists of a soft surface layer on which the horse works that provides cushioning and traction. Beneath this you have the base layer which provides a stable, uniform platform to the working surface.
• All soil will have to be excavated until a good base, usually clay, is achieved. Some arenas truck clay in to form a sound base. It may be advisable to try and find a site near the arena to dispose of the material or use it for landscaping features and seating embankments rather than trucking it away.
• Ensure that no sediment from the site can enter waterways or streams during construction. Local or regional councils can prosecute both landowners and contractors if muds enter streams. Any disturbed ground (including topsoil removed from the arena site) should be regrassed immediately. Spreading hay over the disturbed ground reduces runoff in heavy rain and promotes grass germination.
• A basecoarse rock should be evenly spread as the first layer to a depth of at least 100mm and rolled with a compactor. Water can be added during this process to aid compaction. It is important that the sub base is firm enough so the horse's hooves do not dig this layer up. If an arena measures a standard 40 metres by 60 metres, it will require about 240m³ of basecoarse, weighing about 380 tonnes (13 truck and trailer loads or 38 truck only loads).
• Depending upon the nature of the basecourse, some arenas then have a layer of limestone followed by a finer rock to seal the sublayer from the sand carpet

Geotextile:

Surface Material:

• The surface material should be a loose free draining material, usually sand. A good surface will provide good traction and a consistent base. Too hard and you run the risk of injuring the horse through too much impact on the horses joints and bones. If the surface is too soft, the horse can develop muscle strains from overwork.
• The surface material should be free of rocks that can cause hoof injuries or hit riders, other horses or spectators. Sand should be free of silts and clays, which can cause excessive compaction and reduce drainage as well as produce large amounts of dust in drier conditions.
• McCallum Bros Ltd has a range of equine products suitable for use as surfacing material for horse arenas. These products are natural marine sand mixes screened to remove large items that may cause injury. The products are washed free of silt and clay which can cause excessive compaction and reduce drainage as well as producing large amounts of dust in drier conditions. They are entirely free of pumice which crushes easily to produce a fine dust that is very undesirable to inhale. The particle shape of the McCallum’s equine mixes is classified as angular to sub angular providing a stable surface for the horse to work off. They are suitable for use by themselves or in conjunction with other footing materials.
• We recommend the top layer of McCallum Bros. Ltd equine mixes should be about 100mm deep. On a standard 40 metre by 60 metre arena, this will require about 240m³ of sand, weighing about 320 tonnes (11 truck and trailer loads or 32 truck only loads).

View the McCallum Bros equine products page

Care and maintenance:

• Avoid using the arena immediately after heavy rain as this will damage the base layer, causing rock and other material to migrate to the surface and may lead to hoof bruising. If clays within the base layer migrate to the surface the sand's drainage ability (hydraulic conductivity) will be reduced and it will lead to increased dust problems in dry weather
• The completed arena will require periodic maintenance. A light set of harrows or levelling bars pulled by a ute, quad or small tractor will redistribute the sand evenly over the arena. It is important that the base layers are not damaged. Compacted areas need special attention and frequent use by horses in some areas will result in the reduction in sand layer depth.
• Over time, surface sand will be lost through use. It is important that the base layer is maintained with 50-100mm sand to prevent stone bruising and mixing of the sand and base materials.

Recommended Contractors: