Monday, July 12, 2010

Anatomy of a Shallow Well Part 1

Foster having a look at the stand for the pump, and half completed concrete apron Today was a whirlwind of a day. I was sitting at home, reviewing the requirements for my University of Waterloo work-term report when Foster, my counterpart and host-father bursts into the house clad in motorcycle gear and says, “Danny, we must go see the well. Time is against us.” So I strap on my motorcycle helmet and we jet off to Mwambazi, a village in the Timbiri Traditional Authority (TA), the same TA in which we live. It’s there that World Vision, an NGO that needs no introduction has funded the construction of a conference centre and nursery, and has hired Foster to install a shallow well to provide safe, clean water to the facility.

Foster, showing the shallow well he will be building a cement apron for to protect it from contamination.When we arrive, it turns out time wasn’t against us, and we are the first there so Foster shows me the well shaft which has already been dug and lined with bricks and cement mortar. Fairly quickly the rest of Foster’s construction team arrives and we get to work. The first task is mixing the cement with sand, gravel and water to obtain the correct consistencyMixing gravel into the concrete.

 

 


While the mixing is being done, Foster calls for the housing for the pump. The one provided for this job by World Vision is an Afridev model, a fairly standard and durable pump. This pump is however designed for boreholes and not shallow wells. The housing has 3 legs with jut down and are wide enough to support it in a borehole, but not wide enough for a shallow well. To compensate for this Foster places the housing in a hole, and fills it with sand. A little bit of creative construction, putting the casing in a hole to build without including the Afridev-designed legsThis will allow him to build the concrete skirt which protects the well above the level of the legs, which will simply hang down into the well.

Normally the Afridev pump is used for boreholes, which are narrower wells dug by a drill rigs. Boreholes go much deeper and are able to tap aquifers which are unreachable by hand dug wells. In the case of this well however the aquifer is very close to the surface, only two or three meters down and, as Foster puts it, “You could use anything to reach this water.” The Afridev is very durable, efficient at pumping and spare parts in the case of a breakdown are more readily available than any other pump model, that’s why World Vision has chosen to use it for this installation. It is however more expensive.

Yolam taking a trowel to the first layer of concrete and rebar in the apronNext bricks and a sheet of plastic are laid down to give the apron shape, and the region is filled with concrete.  Segments or rebar are added to the concrete, to increase it’s strength and flexibility. Once the mould is filled, Yolam Kamanga, Foster’s Nephew (who has also been trained as a Marion Medical Mission Maintenance Assistant for that NGO’s water points) smoothes out the layer.

The concrete shelf where the spillway will be sloped from Next, moulding for a second layer is added, and a shelf is created out of the concrete. This will allow a spillway to be added after the concrete sets so that water drains away from the pump and doesn’t lie stagnant allowing mosquitoes to breed.

The concrete takes approximately five days to set so we won’t be returning until Tuesday to move the apron over the open hole and complete the rest of the concrete “civil works” which surround a protected water point as well as install the pump. So there’s still much to do. Tune in next time for part 2!

The team, from right to left: Yolam Kamanga (Maintenance Assistant/Builder), Foster Longwe (Supervisor), Name Here (Village Headman), Name Here, Name Here

To see all the pictures from today, have a look at the link below:

 

 

 

Daniel

6 comments:

  1. Yo, it sounds like you're learning so much, I find that really fantastic. Aside from the soft skills, business, life, etc you also get to learn a lot of cool engineering skills :)

    I'm drinking Argentinian wine, eating watermelon, just chilling. I wish you were here, but I also wish I could come experience all that you're writing about - it sounds like an adventure and a half! Keep it up! :)

    Much love,
    Julia

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  2. Another great post :) From everything you've told us about Foster, he sounds like a very busy guy! Installing new wells, maintaining older ones, selling maintenance parts, etc. How does he balance his time between everything? Does he prioritize certain things over others (ie. spending a day installing a new well vs. repairing a couple pumps)

    Can't wait to hear more!

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  3. Thanks Olivia, you definitely bring up a good point. For any business person, how to prioritize your time is a huge question to address. Foster is definitely as shrewd a business person as I've met, in Malawi or Canada, and his prioritization is simple, he follows the money. Foster is very frank and essentially every action in his day boils down to his ability to continue to feed his family. Unfortunately this means that he rarely does repairs on existing pumps because, thought installations like I describe above are funded by NGOs, the community is expected to collect funds to pay for maintenance. This model rarely works, and in my opinion is the reason most well pumps fall into disrepair. My placement was to look at private ownership and whether people would be willing to pay for their own wells, or "self supply" and if the large initial investment of paying for the well installation, and sense of ownership would increase functionality rates. However Malawi has set delay after delay in front of me and it looks like I may get to see some wells installed with manual drilling, but for Water 4 People, an NGO and not a private individual. That is course not to say that this hasn't been (but continues to be!) an amazing learning experience.

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  4. Hey Daniel!
    I am probably in the same timezone as you right now, which sometimes makes me miss you a little less since it's not as far away as canada is.
    I can't wait to see you already and hear even more stories. It's probably hard to capture it all into the blog, and I know you have limited internet access, but in any case I just wanted to let you know that I am reading it and wishing you the best there.
    Keep up the good work,
    tanya

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  5. That is why a good idea is you need to connected examine prior to producing. You can actually distribute greater distribute this way. submersible vs external well pump

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  6. Superbly written article, if only all bloggers offered the same content as you, the internet would be a far better place.. cheap water pressure tanks

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