Many outdoor arenas demand footing that will please a lot of people. From western pleasure to speed events, all-purpose arenas must have safe, durable footing that will hold up without being too deep or too slick.
Bob Kiser, owner of Kiser Arena Specialists, points you in the right direction for footing material you can use for just about any event.
The key components are a drainage layer, followed by a base of sandy loam and topped off with a dirt-sand mixture.
Before you dive further into Bob’s arena recommendations, here is the soil-savvy vocabulary you should know:
• Plasticity Index – A measure of the soil’s density.
• Clay – The finest soil particle.
• Sand – The largest soil particle.
• Loam – A medium-sized soil particle.
• Hard Pan – A layer of extremely hard-packed soil.
• Particle Size – The size of each grain of soil, measured by which screen it passes through.
• Screen – A series of pans with different sized openings to measure particle size of a material.
• Percolation – Upward and downward water movement through soil.
Drainage For Your Arena
“Start on a drainage before you ever build your outdoor arena,” Bob says. “When you shape your arena, you should ideally put plastic, perforated tile in your arena, if your soil or base material will support that and percolate water.”
When water runs down to the perforated plastic tile, it is directed out of the arena.
If your only available choice in base material is a high Plasticity Index material with slow percolation, such as 20-25 PI clay, you’re better off skipping the tile layer, because the water will never drain down to the tile, Bob explains.
“If you’re going to spend the money to put tile in, you want to make sure your ground will percolate water,” he says. “It has to go through the soil profile to get to the tile.”
You can improve clay with a moderately high PI level (slow percolation) by filling the tile trench half full of pea gravel with a layer of sandy loam on top.
“When water hits the rocks, it’ll run through to the tile,” Bob says.
If you live in an area where rocks move to the top of the ground, you can add a geotech fabric, which is used under some highways, over the rock layer.
Choosing the Right Soils
Unfortunately, your sand-soil layer has no magic formula for perfection. Your footing will be dependent upon the particle sizes of the sand and clay available to you. Be prepared to gradually add more materials to your arena until it provides drainage, strength and stability, he advises.
It’s important for your surface to bind together and be firm, but it shouldn’t pack too easily or your footing will get too hard to quickly. Use enough sand to ensure that your surface doesn’t pack.
“There is no such footing that’s perfect for every event,” he continues. “You have to hit the center of the spectrum that’s a useable footing for any event.”
Build Your Outdoor Arena Right
Don’t be afraid to get help with your outdoor arena. It’s an investment you want to last a long time, so it’s wise to do it right the first time, he says.
“A lot of people will try to build an arena themselves without any help, then they end up having to pay someone to redo it,” Bob says. “It’s like building a house – you’re better off hiring a good general contractor and paying him what he’s rather than thinking you can do it all yourself.”
And, no matter who builds your arena, proper maintenance is key for its longevity.
“With any arena – no matter how good the material – the equipment and your knowledge of the equipment are key,” Bob says. “You have to have the equipment and the knowledge to maintain your arena. A lot of people make the mistake of hiring someone to put the arena in, then failing to buy good equipment and learning how to maintain the arena after it’s built.”
Courtesy of America’s Horse Daily