The most common complaint among dressage riders is dusty footing, great billowing clouds of the stuff. It’s kicked up with every step. It hangs in the air for what seems like forever. It gets on your clothes, your tack, your horse. It makes its way into the lungs. Even an outdoor arena with a breeze doesn’t offer much relief. And when the dust gets so bad that the arena requires frequent watering to hold it down, the footing compacts as it dries. Out comes the harrow to break up the compaction, but that releases dust. Out comes the hose, but that restarts the compaction process. And the cycle continues. Common causes for dust include interior stalls, old bedding, hay and the arena footing itself. In this Equisearch segment, Brian J. Fahey explains how to water a dressage arena correctly to keep the footing from releasing dust.
How to Water Your Dressage Arena–The Math Behind Moisture Content
It’s possible to determine how much water an arena needs by utilizing a mathematical formula known as the “watering increment principle.” Here’s how it goes: For every 1,000 square feet of arena surface–where the footing is three inches deep–apply 19.5 gallons of water for a 1 percent increase in the moisture content. That’s fine, you may say. But I want to reach 10 percent moisture content. How do I figure out how many watering increments to add?
For that, you first have to know the percentage of moisture content in your footing. Thankfully, it’s easy to determine. You know those probes you use to measure the moisture content of hay bales? Stick one in the sand about halfway down, and read the result.
Perhaps your footing contains 3 percent moisture and you want to increase it to 10 percent. That’s seven watering increments or 136.5 gallons per 1,000 square feet of surface area.
Since most folks don’t have a flow meter on their hoses or sprinkler systems, you’ll probably need to figure out how many minutes to water per watering increment. You can do that by setting up your hose the way you normally do to water the arena. Take a five-gallon bucket, turn on the hose to its normal flow rate for watering and count how many seconds it takes to fill the bucket to the brim. (For sprinkler systems, put the bucket in the arena and let it fill.) Now divide the result by five to determine seconds per gallon. Take the reciprocal of that number (the reciprocal is either of a pair of numbers whose product is one, example: 2/3 and 3/2) and divide it into one to find gallons per second. Now multiply by 60, and you have gallons per minute. Divide that number into 19.5, and you have watering increments per minute.
Once you know how many watering increments you want to add, divide that number of watering increments by the watering increments per minute and you have the number of minutes to water per 1,000 square feet. Divide the total square footage of your arena surface by 1,000, and multiply that by the number of minutes per 1,000 square feet you just calculated. And there you are. Whether by hose or with a sprinkler system, you now know the total watering time.
Knowing how to water your dressage arena is only one component in correcting footing problems. Some are easy to figure out and fix. Others are complicated and require a deeper understanding of how and why things happen to your arena. In the November 2001 issue of Dressage Today Brian J. Fahey gives hands-on strategies you can use to restore the footing in your dressage arena.
Fahey is a designer of indoor and outdoor riding arenas and has published many articles discussing design, repair and rehabilitation options, including dust testing and control, footing mixes and specifications, footing moisture content and riding arena safety and risk management. He also pursues a vigorous research program into improved approaches to arena materials, performance specifications and design concepts. Fahey lives in West Lafayette, Ind.
