- Messages
- 2,756
- Reactions
- 5,885
Underground water vs. captured runoff.
Captured runoff mostly would otherwise end up in the ocean, less what evaporated or percolated into the ground. The bulk of runoff makes it to the ocean/sea.
Underground water that is pumped out has accumulated over long periods of time. It is refreshed by percolated surface water, either rainfall/snowfall or what percolates from surface lakes, streams, rivers. Without pumping, the underground aquifers reach a stable level that will be limited by geologic formations. Excess underground water generally escapes as springs, or establishes the static level of lakes or ponds.
When the static level of underground water keeps falling, more is being pumped than can be replenished by current precipitation, and the trend cannot be reversed unless we reach a wetter climate cycle. In much of the world control of underground water is a "hot-button" issue, because adequate water supplies are critical to life, and beyond that, critical to quality of life.
There is a point beyond which pumping is unsustainable, impractical, and destructive.
Captured runoff is a limited resource, based on precipitation. If more is used/released than falls, the volume in the reservoirs drops, and can run dry. Too much precipitation, and it must be released, lest the dam overtops and fails. This is like "carrying capacity" of land. There is only so much.
Underground water is of such a massive scale that earlier generations regarded it as infinite, which it is not. Until society admits this, it will continue to be used up.
Captured runoff mostly would otherwise end up in the ocean, less what evaporated or percolated into the ground. The bulk of runoff makes it to the ocean/sea.
Underground water that is pumped out has accumulated over long periods of time. It is refreshed by percolated surface water, either rainfall/snowfall or what percolates from surface lakes, streams, rivers. Without pumping, the underground aquifers reach a stable level that will be limited by geologic formations. Excess underground water generally escapes as springs, or establishes the static level of lakes or ponds.
When the static level of underground water keeps falling, more is being pumped than can be replenished by current precipitation, and the trend cannot be reversed unless we reach a wetter climate cycle. In much of the world control of underground water is a "hot-button" issue, because adequate water supplies are critical to life, and beyond that, critical to quality of life.
There is a point beyond which pumping is unsustainable, impractical, and destructive.
Captured runoff is a limited resource, based on precipitation. If more is used/released than falls, the volume in the reservoirs drops, and can run dry. Too much precipitation, and it must be released, lest the dam overtops and fails. This is like "carrying capacity" of land. There is only so much.
Underground water is of such a massive scale that earlier generations regarded it as infinite, which it is not. Until society admits this, it will continue to be used up.
Last Edited:
