Rainwater harvesting or more specifically in cities storm water harvesting , can be used to recharge bore wells.
From a catchment area of roughly 2000 square metres of hard surface, storm water runs to this recharge structure around a bore well.
A pit of roughly 2m x 2m x 3m deep has been dug. It is then filled with large round stones to 1 metre depth, small stone for another metre (40 mm dia) and then with coarse gravel for about 50 cm. A 50 cm gap is left for water to hold and seep in.
Holes have been drilled in the casing where the big stones are in the pit and then covered with a mosquito mesh made of nylon.
Water percolates through the sand, stones and goes into the casing of the well. As you can see the recharge rate is about 100 litres a minute.
This particular bore well has been sunk to a depth of 100 metres and is now abandoned because it ran out of water.
As a recharge structure it is excellent for storm water control and for ground water recharge. A strategy perhaps for better rainwater management in cities?
Indeed it is...
zenrainman 1 year ago