Tuesday, April 2, 2013

Hand-dug well part 2 (with pictures!)

Today I was back at the village where we're finishing up a hand-dug well.  Everyone was excited about today because we were bringing the big water pump and electrical control box, and we were going to get it all hooked up.  Before I explain the day, here's some pictures...

What once was a rocky hillside is now a 43 meter deep hole in the ground!  The wood and steel rope spool that rests on the barrels filled with sand is the only elevator.  Simple, but it works.


This is the big pump, housed in the yellow barrel.  The 1.5 kilo-watt pump is  spec'd to push a 2" flow of water up to 120 meters of vertical head.  The yellow barrel will keep the pump upright in the 80cm diameter well, and protect it from sucking sand up from the bottom.


 Here is the control box that houses the automatic pump shut-off.  A big pump like this requires a starter (top right), but the power going to that can be interrupted by an electrical relay switch from a Toyota Landcruiser (top left).  The relay switch is operated by a float switch that is attached inside the barrel, beside the pump.  The idea is that when the water is drawn down to a few inches above the intake on the pump, the float drops, tripping the relay, shutting off the pump.  This is all thanks to my German teammate who makes control boxes for micro-hydroelectric power plants.


After a busy morning of work at the well, the men from the village were more than happy to invite their foreign guests up to the community room for a celebration lunch.  This time with the men is probably equally important as the work itself, in both the eyes of the villagers, and ours.  The menu included: rice, meat, bread, potatoes, apricots, oranges, apples, yoghurt, and Pepsi.

After lunch I saw the well digger catnapping in the grass.  When he saw me he rose to attention, so I asked a couple guys to join him for a picture.  (Left to right up front: Project facilitator "Harry", the infamous well digger, and another consulting well digger who everyone likes better because he weighs about half of what the big well digger weighs and that makes him much easier to raise and lower in the well.)


After lunch we straightened the pipe and wires that attach to the well, and started to lower it down the well.  Unfortunately this was harder than expected.  Part of the reason was that we could not suspend the pump and barrel from dead center because of the position of the pipe and the lowering hooks.  The other part of the problem was that the well shaft turned out to be... not as straight and consistent in width as the well digger said it was.  Here's the well digger ready to climb down the well to see if he can help guide the barrel and pump to the bottom.


Most of the afternoon was like this: a small crowd gathered in anticipation of the big pump being turned on and water being pumped to the reservoir in the village, but everyone ended up doing a lot of waiting because the well digger had a lot of difficulty lowering the barrel all the way to the well floor.  When he finally emerged from the well he said, "well, the barrel is down, and it will probably never come back up, and one of your shovels is underneath it, sorry about that."   


 Despite the lost shovel, we decided to hook up the electrical and see how the pump worked.  Starting the pump caused a 30-volt drop in the electrical source (which might require heavier supply lines), but then the pump ran strong.  In this picture we are timing how long it takes to fill a 220 liter barrel.  Unfortunately before it filled the pump stopped, because the water level had already dropped to the level of dropping the float switch.  This was disappointing to everyone, because they certainly need more water than that for the village!  Discussing this with the leading men who were there, we all agreed that it was the well digger's responsibility to get the pump and barrel deeper into the water.  Our time was up and we needed to head back to town for other meetings, so as I left the well digger was climbing down the well again to get the shovel out from under the barrel, and push the barrel all the way to the bottom of the well.  I hope he succeeded!

What remains:
-The output pipe from the pump needs to be connected to the pipe that runs ~600 meters up to the village reservoir.
-The electrical lines from the pump need to be buried from the well to the control box.
-A 60cm cement ring needs to be set on top of the well, and a 20cm x 20cm cement "sofa" ring around that, sealing it.
-The well, pipe, and reservoir all need to be shock-chlorinated to kill any contaminants introduced while constructing the water source.
-Completing the terms of agreement in the community's water committee, to ensure that responsibility will be taken for this new resource.

If you really liked learning about our well project, you might be interested in backing up now and reading part 1 of the story by clicking here.