The water that flows out of spring once fell as rain. The rainwater soaks into the soil and enters into rocks through cracks. When water finds a natural opening in the ground that is below the water table, only then a spring occurs. That's why most springs are in valleys or low places. Some springs receive water from deep within the water zone. These usually flow all year and are called “permanent” springs. Other springs have their openings near the water table. They usually flow only in the rainy season when the water table is at its highest. These are called “intermittent” springs. In some places, especially in are as where there have been volcanoes, the water in springs has been in contact with hot, underground rocks. This type of spring is called a “thermal,” or “hot” spring.