After the air we breathe, water is the most cockily presumed commodity in our lives. With various degrees of certainty, we all believe there’s enough out there, somehow it will never run short and if it does, why, is there not desalination or some other technology fix?
Water needs greater respect and care than our mindset presently allows. Unlike air, it is not ubiquitous. It is more vulnerable than air to man’s willfulness. Fortunately, it is also very responsive to well-informed initiatives. So it is profitable to learn the life and times of water.
Every single drop of freshwater on this planet comes from rain. [It’s worth repeating that sentence.] Where does it all go? A lot of it into the ground and shallows, ponds and lakes; the rest of it runs into the sea. [Incidentally most of what goes into ponds and lakes also gets into the ground.] If the land is treeless and barren, rainwater roars along taking away soil with it; it has nothing to impede it so that it may percolate into the soil. If there are trees and woods and leaf piles and other impediments, there will be plenty of time for it descend into the soil.
Once it enters the ground, if the soil is sufficiently porous [-made so by presence of rocks and pebbles, with thousands of cavities between them] water fills the voids. Such a soil is known as permeable and is filled with water to saturation, as long as enough comes seeping down. Permeable soil with water resident in it, represents what is known as an aquifer. Clay or monolithic rock are impermeable and descending water slides over them and travels horizontally, till finds permeable soil.
Although one commonly hears of underground springs or rivers, there are no such formations; water in an aquifer can be contiguous and vast but not in as in a river.
It is crucial to dig or drill for a well in an aquifer. Surrounding water then drops into the hole via thousands of weepy eyes on the well’s inner wall. The wikiPedia explains the terms well: “The beach provides a model to help visualize an actual aquifer. If a hole is dug into the sand, very wet or saturated sand will be located at a shallow depth. This hole is a crude well, the wet sand represents an aquifer, and the level to which the water rises in this hole represents the water table.”
These reflections finally led me to understand what was happening at pointReturn. The borewell is indeed located in a good aquifer and there is some water left in it. But not enough. The aquifer is a good sponge but not much water got in to soak it full. Most of it raced down the slope, and on to the village lake. [That happened because the land is bald] This being the very nadir of summer, and since the last rains fell six months ago, there is little water arriving at the borehole to feed the pump’s needs steadily. That explains the pump going dry and resuming, when water is recharged.