January 2012 -- Anyone who has been around tennis courts for any length of time has had the opportunity to dry hard courts after a rain. We all have had the need to either get tournament matches started or get our own match underway. Even though many people have spent hundreds if not thousands of hours in this pursuit, it is interesting that we've not seen an article dedicated to drying tennis courts. Before you can teach the modern game or develop a sophisticated training session, you have to have a dry court. After many years of personal contemplation and extensive practice, I thought it time to reflect on the various aspects of court drying and supply my own thoughts and considerations for the benefit of those who have struggled to find the best practices for this daunting endeavor. There are a number of considerations before beginning that include the condition and grade of the courts, weather conditions, and various techniques that may help you develop a deeper understanding and passion for this skill that is critical to our industry.

Court conditions and drainage
Courts should be as flat as possible, but not level. For many years, courts have been designed to drain in one direction or another. The typical grade to a court is around 1 to 10. This means that the court will have a one-inch drop for every 10 feet, either from end-to-end or side-to-side. This slight grade is unnoticed by the players, but makes a huge difference when considering the drying rate. If the court is "flat" with the proper grade, then there will be very few "birdbaths," or puddles, left on the court after water has drained off. If the court is relatively level, it doesn't drain as well and it is more likely to have puddling.

If it drains, which direction does it drain? You would likely want to start roll drying on the high side, where much of the water has drained off, before working your way over to the low side.

Does it have "birdbaths" and, if so, how deep are they? Water in large puddles should be pushed downgrade so that it can also drain off the court.

Weather and drying conditions
Drying conditions is the most important factor to consider. The weather conditions will determine if that court will dry in 30 minutes or three hours. Wait a while after a rain to allow drainage to move most of the water and wait for drying conditions to improve. Water will evaporate when its temperature rises above the dew point. A good time to begin is when you start to see dry areas on the court. This gives the court a little time to drain much of the water off rather than spreading it over the court. It also allows time for the humidity levels to drop and the dew point to rise to a level more conducive to drying.

The wind and sun are your biggest allies when drying a tennis court. You really don't dry a court, but help with the drying process. A breeze will increase air flow over the surface of the water and the sun heats up the court and water to further speed the drying process.

From late fall to early spring in the northern hemisphere, the sun is low in the southern sky and temperatures are cooler. This time of year there are longer shadows from the windscreens and trees. Areas without direct sun will be the slowest to dry and should be your primary focus.

Tools
Roll dry versus squeegee: Squeegees are good for pushing water. They are inexpensive and can be purchased at the local hardware store. However, by far the best tool for drying hard courts is a roll dry. A tennis court has roughly 7,200 square feet of surface area. Water will only evaporate on a tennis court that is in contact with the air. If used properly, a roll dry works by spreading water over the court to increase the water's surface area. The larger the surface area, the faster water will evaporate. Roll drys help spread the water more quickly and more efficiently than a squeegee or a towel.

Techniques
Technique is the topic that creates the most debate. Back in college, my buddies Robert Cox, Ray Anders, and I would critique each other's technique. Should you follow a straight line or walk in circles, use a crisscross pattern or diagonals, or make circles or seashell circles from the center?

Any technique is better than sitting on the side waiting for the court to dry on its own. My high school coach, Novice Kniffen, would have us out on the courts shortly after a rain. He would make an agreement with the tournament director that would give court assignments to those who helped dry courts. He didn't care what technique we used. He knew that it would get the matches on sooner and that we would be warmed up from walking while also getting mentally ready to play the match.

Methodology
Pushing down hard on the handle of a roll dry turns an expensive roll dry into a simple squeegee. I will typically apply a little pressure to a roll dry when in a dry area of the court to remove some of the water from the sponge before walking over a wetter area again. Sometimes you have to pick up a roll dry to change directions or move to another court. Otherwise, do not carry a roll dry around the court. The best practice is to push the roll dry and spread the water by rolling it over dry areas, while also removing water from the sponge so that it will pick up more water in the wet areas. Only on large puddles or puddles near the edge of the court will I use the roll dry briefly like a squeegee to push the bulk of the water downgrade or completely off the court.

Patterns
My favorite pattern often includes a spiral pattern (Figure 1). This is due to the courts staying wet longer on the south end from the shading I referred to earlier. The spiral helps move water from the shaded areas out to the sunnier areas and is a very good method for spreading the water as thinly as possible. As the sun heats up the court from direct sunlight, the increase in temperature along with the greater surface area speeds evaporation.

By following straight lines similar to mowing grass (Figure 2), it ensures that the entire surface of the court is covered. However, pay attention to the particular areas of the court that may have more water and make sure that your pattern includes continued focus on these areas.

Making the seashell circles from the center of the court outward (Figure 3) is a very effective technique on courts that are level. Water is not going to drain off well and must be pushed off the court. Large puddles will dramatically hinder this technique and should be pushed or spread first to prevent flow-back behind you as you make your seashell circles.

For small puddles, it seems to work well to push and pull the roll dry back and forth over the puddle while slowly walking in a circle around the puddle in a star pattern (Figure 4). It will help spread the water quickly in the deepest part of the puddle.

There is a law of mathematics that I'm not sure Einstein considered in his time. If one roll dry works well, two roll dries are twice as good. The faster the water is spread, the sooner the escalated evaporation process will begin. Whichever pattern you use, walk fast and spread the water till it is very, very thin and let the sun and wind finish the job.

The slope of the court, drying conditions, and your methodology are important considerations when developing your plan. Through years of experience, many of us have had ample opportunity to contemplate the techniques that work best. There are a number of things to consider when planning your attack. With a good plan, you will be "on a roll" to getting back on the courts playing tennis.