|Better Farming Series 28 - Water: Where Water Comes from (FAO, 1981, 31 p.)|
|Why we study water|
17. When it rains, all of the water may not go into the ground. Some of it may stay on the surface.
Water staying at surface
18. Water which stays on the surface will either lie in one place, if the land is flat, or it will run along the surface, if the land is hilly.
Water at surface: staying or running along
19. The water that lies on the surface is called surface water. The water that runs along the surface is called run- on water.