The 60m/200ft deep well of the Serai took three years to dig with a hammer and a chisel. The main vertical shaft is roughly 0ne-metre in diameter. At a depth of 43m/141ft there is a horizontal tunnel, 1.1m high x 1m wide, that stretches 16m/52ft in an Easterly direction.
I think of it as more of a mine, a water mine, that harvests its H2O from a 1.1m thick layer of wet, grey-green clay. The water seeps slowly out of the walls of the horizontal tunnel, trickles along the floor of that tunnel and then drops into the vertical shaft. When the well is full, the water level sits at the top of the tunnel, so the lower 17m of the vertical shaft are full and the 16m tunnel is full: about 31 cubic metres of water, or 8,200 US gallons. That’s a useful amount of water, but sadly the clay is prone to drying out and it does not recharge very quickly. The best rate of recharge we ever had was about 800 litres a day. More usually it is 200 litres a day and after several months of summer drought it’s zero
If i want to double it’s output I only have to dig another 16m of tunnel. Erm…..