Friday, April 15, 2011
Refurbishing the well: design and execution
When we bought our coffee land, the real estate man, Gabriel, from whom we bought it, had dug a "well" on the common land shared by the three lots. He'd simply dug a hole on the line of a spring and it filled with water -- enough for watering plants, mixing concrete, etc. However, the walls would cave in from time to time, and the well would silt up. It would have leaves and twigs and small bits of branch from nearby trees floating on the surface. It served well for 5 years, but now that we are putting proper gardens in and wanting to get some turf down and make a nice outdoor living space, it was time to refurbish the well -- to find a way of keeping it clean, to give it proper walls and a cover, and to make something that was easy to clean.
We thought long and hard about how to do it, and eventually came up with the idea of using one of the large plastic water tanks that are on top of almost every house here: invert the tank, sit it on a bed of clean stones, drill holes in the sides and the bottom of the plastic (which was really the tapered top of the original water tank), and fill all around the outside of the tank with clean rock, providing a filter between the earth sides of the well shaft and the outside of the plastic tank.
Basically, the job would involved emptying the existing well and digging it much deeper, so we could have a relatively narrow and deep well interior. A couple of days ago we began the work, assisted by our neighbour, David, who we pay to do a fair bit of work with us, especially in the seasons where there is not a lot of other work available for day labourers. David had never dug a well before, and neither had we. And no matter how much we'd tried to explain the concept of the inverted tank he just didn't get it.
After all, no one builds a well like that.
David suggested to Michele that he had no idea whether it would work or not, but he was prepared to dig on, in faith that it might. Good faith, because it was a hot day.
The hardest part was always going to be digging out -- clay -- as fast as possible to keep ahead of the incoming water. There was so much silt in the well we would sink almost to the top of our long rubber boots and then need to get help from the other to get free. Eventually, I figured we could use some timber to stand on, and we had a few lengths of stout timber around a meter or so long, and they proved to be excellent static surf boards from which to excavate.
So we got started by draining the original well.
With the tank in place and the rock filled around the sides, the well looked like this.
It was time to cut out the original base of the tank, which is now the top of the well, after which we would know if the design had worked. That was a job for a simple fine-toothed hand saw.
Really interesting and neat to see it.
Links to this post: