After rain, where does the water go? Some water soaks into the soil. This is called infiltration. The rest flows over the ground into streams and rivers.
An asphalt school playground has a sealed surface. This means that very little water can pass through it into the soil. Most rainwater flows over the top. In heavy rain, a lot of water can reach the drains in a short time.
A planted school playground handles rain in a different way. Water can soak into the soil among the plants. The soil holds some of this water for a while.
Plants take up some water from the soil. They release some of it into the air through their leaves. The water turns into a gas. This change is called evaporation. It helps to cool the area.
But soil cannot always take in all the rain. How much water soaks in depends in part on the type of soil. It also depends on how wet the soil is before the rain starts. If the soil is already very wet, less water can soak in.
A planted area can take in and hold more rainwater than asphalt. But even a green area may not cope with heavy rain. More rain may fall than the soil can take in. Some water then flows over the ground.