Better Farming Series 28 - Water: Where Water Comes from (FAO, 1981, 31 p.) Where to find water in the ground (introduction...) Wells Springs

Better Farming Series 28 - Water: Where Water Comes from (FAO, 1981, 31 p.)

Where to find water in the ground

72. We can find water in the ground

· in a water- carrying layer;
· at the level of the water table;
· on top of a solid rock layer;
· in a broken rock layer.

73. If there is a layer of sand, pebbles or small stones in the ground, sometimes water gathers there and begins to run through the layer.

Water runs through the layer

74. This is called a water- carrying layer.

75 A water- carrying layer may lie near the surface or it may lie deep in the ground.

76. A water- carrying layer may be very thin or very thick.

77. A water- carrying layer may be very big or very small.

Wells

78. When the water table is not too deep in the ground, we may be able to dig a hole down to the level of the water.

A dug well

79. This is called a well.

80. If the water table is very deep in the ground or if the water sinks into broken rock we may be able to drill a deep well down to the level of the water.

A drilled well

Springs

81. Sometimes a water- carrying layer comes to the surface, as in hilly land, and water flows out of the ground.

Water flows out of the ground

2. This is called a spring.

83. how much water we can take from a spring depends on how much and how fast the water runs through the water- carrying layer and the slope of the layer.

84. During how much of the year we can take water from a spring depends on how much it has rained and over how big an area it has rained.

85. Some springs give water all year long and some springs give water during only one or two seasons of the year.