4 ms·
I didn't realise the water table at higher elevations could be above the ground level of nearby lower elevation land, so I had the same issue. When I first read
by strken 3y ago
I didn't realise the water table at higher elevations could be above the ground level of nearby lower elevation land, so I had the same issue. When I first read the article I thought a qanat was a type of stepwell[0].
[0] https://en.wikipedia.org/wiki/Stepwell https://en.wikipedia.org/wiki/Stepwell
- Zanius 3y agoThe water table typically rises and falls with elevation. Depends on the kind of rock/soil in the area.
- strken 3y agoI knew that was true across long distances. I didn't realise the water table could be high above sea level at point A, lower at point B, and yet points A and B could still be close enough to each other to manually dig a tunnel between them.