1. Precipitation: This is the most common source. Rain, snow, sleet, and hail all contribute to the water that collects on the ground.

2. Surface Runoff: When precipitation falls on the ground, some of it flows over the surface, carrying with it sediment and other materials. This runoff can collect in rivers, lakes, and oceans.

3. Groundwater Discharge: Groundwater is water that is stored beneath the surface of the earth. When groundwater flows to the surface, it can contribute to water on the ground, forming springs, wetlands, and other features.

4. Human Activities: Humans can also contribute to water on the ground through irrigation, sewage discharge, and other activities.

5. Evaporation & Condensation: Water evaporates from bodies of water and the soil, rises into the atmosphere, condenses to form clouds, and then precipitates back down to the ground. This completes the water cycle.

So, the water on the ground comes from a combination of these sources, with precipitation being the primary source.