Artificial turf fields are watered primarily to cool the surface and reduce the risk of skin burns and abrasion injuries. Unlike natural grass, synthetic turf absorbs and traps heat, and it creates more friction against exposed skin. A layer of water addresses both problems at once. You’ll see crews watering the field before kickoff and again at halftime in soccer, football, field hockey, and other sports played on synthetic surfaces.
The Heat Problem With Synthetic Turf
Synthetic turf gets dangerously hot in the sun. Surface temperatures on unwatered fields regularly exceed 70°C (158°F) on summer days, and multiple studies have recorded peaks above 85°C (185°F). For context, natural grass fields tested under the same conditions typically max out around 37 to 40°C (99 to 104°F). That’s a gap of 30 to 45 degrees Celsius.
The reason is simple: synthetic fibers and rubber infill absorb solar radiation but can’t cool themselves the way living grass does. Natural grass constantly pulls water from the soil and releases it as vapor through its blades, a process that works like a built-in air conditioner. Plastic fibers have no such mechanism, so the heat just builds. Even the air directly above the surface gets hotter. Researchers have measured air temperatures at shin height (15 cm above the turf) reaching over 54°C (129°F) on synthetic fields, compared to the mid-30s on natural grass nearby.
How Watering Cools the Surface
When water is applied to the turf, it evaporates and pulls heat away from the surface, the same principle behind sweating. The effect is dramatic. Research published in Frontiers found that a cooled turf system brought surface temperatures down to 37°C on a hot June day when the conventional synthetic field next to it hit 62.5°C. That’s a reduction of roughly 25°C, bringing the turf to within about 2 degrees of natural grass.
The cooling doesn’t last forever, though. On a hot, sunny afternoon the water evaporates relatively quickly, which is why fields are often watered again at halftime. The rate depends on air temperature, humidity, and wind, but the goal is to keep the surface cool enough for the duration of play. Some newer turf systems store water in a layer beneath the surface and use capillary action to continuously feed moisture upward, extending the cooling effect without constant rewatering.
Reducing Skin Abrasion and Turf Burns
Anyone who has slid on dry artificial turf knows what a turf burn feels like. The synthetic fibers create significantly more friction against skin than natural grass does, and that friction gets worse when the surface is dry and hot. Watering the turf acts as a lubricant, allowing players to slide more safely.
Lab testing has quantified the difference. In one study using samples of real skin, researchers found that skin breakdown on dry artificial turf happened at a shear force of about 38 newtons per square centimeter. On wet artificial turf, skin held up until the force reached 55 newtons per square centimeter, roughly 45% more force required to cause damage. Natural grass was far more forgiving still, with skin breakdown not occurring until forces reached 130 newtons per square centimeter. Wetting the turf doesn’t make it as gentle as real grass, but it meaningfully raises the threshold at which players get injured during slides, tackles, and falls.
Managing Cleat Grip and Traction
The interaction between cleats and synthetic turf is different from cleats on natural grass, and moisture changes the equation. Artificial grass surfaces produce higher rotational traction than natural grass, meaning a planted foot meets more resistance when it tries to twist. That extra grip sounds like a good thing, but it’s actually linked to higher rates of knee and ankle injuries because the foot can get “stuck” instead of releasing naturally during a cut or pivot.
Watering the surface modifies this dynamic. A wet field allows cleats to release more easily, bringing the traction profile closer to what players experience on natural grass. The effect varies depending on cleat design. Testing has shown that certain stud patterns perform differently in wet versus dry conditions, with some cleat types losing too much grip on wet turf and increasing sprint or shuttle times. This is why professional and competitive leagues pay attention to moisture levels, not just dumping water on the field but calibrating the amount to balance safety with playability.
What the Rules Say
FIFA’s stadium guidelines note that watering pitches before the game and at halftime is now common practice, though specific requirements can vary by competition. For artificial pitches specifically, FIFA recommends irrigation systems for cleaning, presentation, and cooling the surface ahead of play, particularly in warmer climates. Other governing bodies in field hockey and rugby have similar expectations. In elite field hockey, a fully watered synthetic pitch is essentially mandatory because the sport’s fast passing game depends on a slick, consistent surface.
Protecting the Turf Itself
Extreme heat doesn’t just affect players. Sustained surface temperatures above 70°C accelerate the breakdown of synthetic fibers, causing them to become brittle, lose their shape, and split over time. The rubber infill granules also degrade faster under intense heat, compacting and hardening in ways that change how the field plays. Regular watering keeps the surface cooler during peak sun hours, slowing this wear and helping a field last closer to its expected lifespan of eight to ten years. Facility managers often water even when no game is scheduled during heat waves for exactly this reason.
The amount of water used is modest compared to maintaining natural grass. A typical sports field irrigation session might apply a quarter inch to half an inch of water across the surface. Natural grass fields, by comparison, need one to two inches of water per week during the growing season just to stay alive, plus all the mowing, fertilizing, and reseeding that comes with it. For synthetic turf, watering is purely a surface treatment rather than an ongoing biological necessity.