Outdoor Riding Arena Drainage
When building an outdoor arena, one of the main considerations is the way the ring will be designed to drain. Fundamentally, there are two ways that an arena can drain excess water: horizontally across the surface or vertically down through the base. A combination of both ways can also be used together in the same arena.
The type of base you choose makes a big difference in regards to how often you have to get your arena re-graded. Your base design also decides whether you can ride during or right after a heavy rain. A base with poor drainage can result in you having to wait a day, or sometimes even several days, to be able to ride. If you have an indoor and can be flexible on where you ride, then waiting for a few days after rain may not be a big deal to you. However, if you’re a busy facility where the arena is in high demand either by boarders or as a show venue, then needing to regularly postpone lessons and events can result in significant lost revenue and a lack of confidence in the venue.
The Main Types of Riding Arena Base Construction
Traditional Compacted Base
A compacted base creates a sealed layer that is built with either a slope or a crown to the base and the footing. Once the footing becomes saturated, this style base will shed water horizontally across the arena’s surface towards the edge of the arena.
Vertical or Free-Draining Base
Why does it matter which direction the water goes when draining from the arena?
The direction of water drainage is the key determining factor for:
1. The amount of time it takes for the arena to drain (i.e. how long you have to wait before it’s suitable to ride on).
2. Footing migration – water traveling horizontally across the surface is going to take some footing material with it. This can be negligible at first, but the footing migration adds up over time. As a result, you can end up with a deep side and a shallow side and an arena that has to be re-graded quite often to correct these imbalances.
Side note: We know some of you aren’t opposed to splashing through a few puddles in your arena (eventers, we’re talking to you in particular). However, this can cause long-term damage to your base, so it’s definitely not recommended!
Which base is best for your arena?
There are pros and cons to consider for each system.
A compacted base is the most commonly constructed type of riding arena.
- Very durable.
- The most economical to build at the outset.
- Surface has to be sloped or crowned.
- It is the slowest of the three types to drain, particularly with larger arenas where the water has to travel a great distance to get to the edge of the ring.
- The water traveling horizontally carries footing with it, which can form deeper footing towards the lower side of the arena and shallower footing on the high side.
- Care must be taken to allow the arena enough time to dry sufficiently before riding after a heavy rain to avoid damaging the base.
The hybrid system is a common “all-weather” arena option that is offered by a lot of professional horse arena builders and offers good drainage in a variety of conditions. This base style is typically in the mid-high price range.
- Good drainage in most rain conditions.
- Surface is still sloped or crowned.
- Vertical drainage capacity is limited.
- Excess water traveling horizontally carries footing with it.
- Footing migration increases the risk of developing shallow areas that expose the geotextile membrane beneath. It is crucial to keep grooming equipment in the top layer of footing to avoid damage to the membrane below.
- Requires a more experienced builder.
A vertical draining base offers the highest capacity and most efficient drainage system of all the options but also requires a greater upfront investment.
- Completely level surface – horses will always go best on a level and consistent surface making this an ideal design for optimum performance.
- No migration of surface materials during drainage so the footing remains in place and very uniform.
- Highest and most efficient drainage in heavy rainfall for a true, all-weather surface in the most challenging conditions.
- Higher price tag.
- Requires highly skilled builder – engineering this style of arena base correctly requires a highly skilled and experienced builder and there are very few builders in the US who offer a true vertical draining system, so you could be facing a long wait-list.
Pro tip: it’s best to start planning at least 6 months to a year in advance for a new riding arena construction.
How to Get Started
The first step is to consult with a TruTex arena specialist to discuss your arena objectives, timeline and budget. We will walk you through the process step-by step and once we have a better understanding of your goals and proposed arena location, we can determine the best arena builder for your needs and get to work on a more detailed quote.