An efficient drainage system is a fundamental element of a horse riding arena, and therefore needs to be a key consideration during the planning process before you begin construction. This is because poor drainage will not only negatively impact the performance and lifespan of your arena’s surface, it could also compromise it’s safety too.
In this article we highlight some of the key points that you need to consider when putting together horse arena drainage plans, and offer guidance on how to design and install the most effective drainage system possible. While this post aims to provide you with useful tips, we also recommend that you consult with a professional installer who has direct experience of planning horse arena developments – as with any job, there may be additional factors that are specific to your requirements and your land, and a well-seasoned contractor will ensure that they are carefully considered as part of the arena plan.
Why Drainage is Critical
As an outdoor equestrian arena is exposed to weather conditions that can vary greatly throughout the year, this can have a significant impact on it’s riding surface and lead to water pooling problems and unstable ground. While this mostly isn’t an issue for an indoor equestrian riding area, indoor setups are still unfortunately prone to shearing, which is where a surface becomes corrugated and uneven after dry areas of an arena have shifted to a moist area – this can make it easy for horses to lose their footing which can be dangerous for both the animals and the people riding them.
While these two issues are very different, strong drainage systems can go a long way to remedying both by controlling and regulating the moisture levels for the ongoing longevity of your arena. Although the installation of a drainage system will increase the initial cost of your horse arena project, in the longer term it will save you money and significantly reduce the risk of surface damage and even horse or rider injuries.
Building Equestrian Arenas
There are a number of key stages involved in constructing horse arenas, which should always include a comprehensive drainage design. Below we have provided a brief overview of each of these stages, along with some pointers you may wish to consider and incorporate into your own horse arena plans.
Choosing a Location
Firstly, you need to choose a suitable site for your horse’s arena, and bear in mind that it will need to offer easy access to riders once it is ready for use, and be accessible to trucks, large vehicles and other heavy machinery that are transporting material and equipment during the construction process.
You will also need to consider the proximity of the arena to a discharge point for any water collected via its drainage system once it’s in place. If you’re planning on expelling water into a soakaway system, make sure there is enough additional space for it to be installed, and if you are going to rely on a natural water source as a discharge point, ensure that it is located nearby (for reduced pipework) and that you have the relevant permission from your local authority to make use of it.
Where possible, it is also worth positioning the arena in an area where it can be – at least partially – protected from the elements by nearby properties, buildings, trees and hedges. To minimise the work required in the excavation stage, you might also want to look for a location that is already reasonably level, and positioned on higher ground to allow water to naturally drain off your finished riding surface.
Your arena size should be dictated by it’s purpose as well as your budget – in general, a 40 metre x 20 metre rectangle arena is best used for novice dressage, while a 60m x 20m is suitable for advanced dressage, and show jumping requires a space that is at least 25m wide.
Excavating the Area
A riding arena needs to include a base layer as well as a layer of the preferred riding surface, which means that, along with the requirement for an installed drainage system, a level of excavation is required. Once the layer of topsoil has been removed from the land, you should dig deep enough to accommodate your chosen drainage system as well as a generous base layer and surface layer, and ensure the excavated area is level.
Installing a Drainage System
There are two main options for drainage within an equestrian riding arena, and which option you choose should largely depend on the volume of expected rainfall and the soil conditions. For relatively dry areas, it may be sufficient to have drainage channels installed along all of the sides of the arena, ensuring that it’s surface has a gentle fall so water can naturally flow into the drains to be carried away.
Alternatively, a more robust solution for areas with heavy soil and frequent rain is to install a series of land drainage pipes in a herringbone pattern, with side branches connecting to a central spine via Y junctions or using a land drain multi junction. The 110mm 3m perforated sewer pipes should be secured between a cover layer and bedding layer of aggregate, and installed at a slight gradient to enable collected water to easily flow through to either a soakaway system or a nearby natural water source such as a ditch or stream.
You can find more information about land drains here in our recent blog post.
Adding Base and Surface Layers
Once your drainage system is installed, you can add a 6 – 8 inch base layer to your equine arena construction – base materials are usually a mixture of coarse stone and gravel that aims to support the top layer whilst also helping water to flow away from the surface. Hardstones such as limestone or granite are usually recommended for this layer, whereas rounded gravel should be avoided, and it is important that the stones are tightly packed to provide a stable foundation.
You should also cover the base layer with a layer Terram T1000 non woven geotextile membrane to stop sand, dust and other materials from working their way into the perforated drain pipes if installed underneath. Using geotextiles not only helps to prevent a gradual build up of sediment within your drainage system, but also stops the sub-layers from mixing together.
For your arena surface, silica sand is by far one of the most popular arena surface materials and it is often augmented with another substance, such as chopped rubber. This helps to retain the moisture of the sand topping and provide a level of cushioning on riding surfaces to protect horses hooves, whilst also improving the ride quality.
Once installed, to ensure that your riding arenas stay in optimum condition for as long as possible, it is recommended that you regularly check your drainage system to ensure there are no blockages that could lead to waterlogging.
It is also advised that you avoid using an equestrian riding arena immediately after a period of heavy rainfall, as this will likely disrupt the sublayers and riding surface, and any horse waste should be removed immediately.
To deal with surface displacement in the most used areas of your arena, you should also regularly level it, and keep the surface lightly damp during dry spells.
If you are carrying out a horse arena development project, check out our selection of drainage solutions available on our website, or call our team for advice and expertise. At EasyMerchant we offer a wide range of drainage pipe products designed for equestrian arena drainage, including, underground drainage pipe, land drainage pipe coils, land drainage multi junctions, Black woven geotextile membrane and non-woven membranes, and Fibreforce 5005 Geotextile adhesive 310ml.
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