Water Technology: The Hippo Roller

Women in South Africa use the Hippo Roller to transport and store water (photo: Hippo Roller.org).

Technology Name: HIPPO ROLLER

Description:
In a nutshell, the Hippo Roller (HR) is a water transporter and storage unit, designed in South Africa.

The HR organizational website has an extensive description about their technology. I'll just paraphrase it for everyone's benefit:

HR is a 20 gallon (90L) polyethylene water drum designed to roll on the ground rather than being carried on the head. The polyethylene is UV stabilized and sturdy enough to withstand every kind of rural condition. To aid input and output of the liquid, as well as cleaning of the drum, there is a large screw-on cap. A clip-on steel handle is used to push the drum around.

HR Specifications:
Year of design: 1996 (I think)
Distribution: 25,000 have been distributed as of May, 2007 (almost all donated)
Size: 20 gallon (90L) drum
Material: UV stabilized, sturdy polyethylene
Features: Steel clip-on handle, Large screw cap (135mm/5.3" diameter)
Cost: US$90 manufacturing + US$10 delivery (the drum is produced in South Africa; delivery costs are in-country as well)

Apparently, the design allows five times the regular amount of water to be carried with a ninth of the force, when compared with the traditional method of carrying water on the head. (If you really want the technical version, the earth balances out a large part of the water+drum weight, leaving only a fraction of the weight and friction for the pusher).

HR also comes with a Hippo Food Security System in place aimed at an average sized family of six. It includes:

• A 210 liter drum for the irrigation system and a 90 liter Hippo Water Roller used for topping up the reservoir.
• 8 x 6 meter drip lines are also included which cover up to 50 square meters of land.
• Tools and instructions and a starter pack of seeds for both the summer and the winter.
• Further training is available if needed.

At the moment, HR is made only in one size.


The Hippo Drum, a closer look (photo source: Project H Design)

My review:
I was browsing through Project H Design's website recently and saw this technology being featured. The H team ended up funding a large project in South Africa in March 2008, which is covered here.

The good:
I've carried my share of water and I can tell you that it is a real pain in the neck (no pun intended). So HR is addressing a real and very important problem.

The concept is simple, replicable, and it works for the processes that it was built for, i.e. storage and transport. The drum has a sturdy construction that can go over all kinds of terrain. It really takes pressure off the women, and she can carry an entire day's water needs in one visit...very efficient!

The what:
I don't think the pushing mechanism works so well if the drum is anything less than full. I've had to roll around half empty barrels on flat earth and uphill (downhill isn't so bad), and the darn thing kept sloshing around. Sometimes going uphill became a battle because the momentum from the sloshing worked against me, and my toes were sore from acting as stoppers!

I'm also not clear on how you fill water from a shallow pool, like if the depth of the pool is less than the diameter of the drum. I guess you have to carry a mug or cup of some sort and scoop the water in. That's the disadvantage of having a big drum as opposed to a 20L jerry can that can be flipped about conveniently.

Another down-side of the mechanism (though not that big a downside) is that sedimentation is slowed down in this case. If you have particularly turbid (muddy) water, then shaking it around just makes the problem worse (carrying water on the head aids sedimentation, making it easy to decant the sample as soon as the bearer gets home).

And what is with the cost?? $90 for a drum?? I understand that things are far more expensive to produce in-country and that there is a social cost to this (hire local unskilled workers, train them, build an industry from scratch, etc). But come on!! You'll be relying on donations for the rest of your life!! (actually is this what is possibly happening with Playpump as well??) I mean...I can clean out one of the ubiquitous steel drums that they have there, have a welder fix me a clip-on (or even permanent) steel handle and sell that for $5 (which is still an unearthly sum, but more consumable and scalable!!). In fact, if I was in South Africa, I'd find a smart, enterprising fellow and invest in him to do this. Trust me, he'd outsell HR and build up a slew of copycats.

Actually this has got me started on a major pet-peeve. Social technology organizations NEED to start thinking about the bottom line. The main goal of ANY organization is to make people's lives easier, so if your technology is really helpful but is not reaching the most number of people it can, you HAVE to ask why and how you can change that. It HAS TO BE SCALABLE. HR is an easily scalable technology, but what is holding it back is the cost. So do what you can to bring down the cost, then use the profits to improve the product (or increase your product line-up) and your marketing model. Don't start with an overpriced technology, you are killing your own success.

And here's another, related pet-peeve...let the poor buy their stuff. STOP giving this away to them for free. It limits scalability and kills the sense of ownership of the owner, which is REALLY important. I have spent considerable time researching the best practices of social entrepreneurs, and I was surprised by how much charity killed the sense of ownership and pride that the consumers had for a particular product. Generally, a technology that required some investment got more respect, was more valued, cared for and gave the owner a great sense of pride. Charity is necessary sometimes, but if you can help it, let the consumer have some pride.

Variations I would suggest:
1. Reduce the cost. $90 is really insane for a plastic drum with a handle. Go for a more affordable, simpler design, and upgrade to the better design as you make profits (which will come with mass production).

2. Each drum has valuable advertising space (even for social messages) that isn't being used. Maybe each woman can sell this space and get her drum entirely subsidized.

3. why not incorporate a simple cloth filter and chlorination mechanism. The water will get basic filtration and be thoroughly disinfected (thanks to the mixing) by the time it reaches home.

4. If you expand the opening and add an extra contraption, the rolling mechanism can make for a spectacular washing machine.

5. HR can also be used as cement/concrete mixer or a leveller (making pathways level). Maybe these women can make extra money by working on a construction site.

6. A kind of line that keeps the lid attached to the drum (rather than it floating away in the river!) would be nice.

7. Another clip on can be using the rotational motion to grind mill flower or just storing the energy as electricity in a battery (but that has its own implications!).

Other reviews/information:
http://www.design21sdn.com/feature/21
http://www.notcot.com/archives/2005/05/design_to_impro.php
http://www.plusonewater.ca/en/FAQ.php#Hippo%20Roller
http://projecthdesign.com/2008/04/13/hippo-rollers-delivered-to-kgautswane/
http://www.treehugger.com/files/2006/12/the_hippo_water.php
http://poverty.suite101.com/article.cfm/invention_for_more_water_in_africa
http://en.wikipedia.org/wiki/Hippo_water_roller
http://www.typepad.com/t/trackback/462659/3401481