The Hippo Water Roller is a barrel-shaped container designed to transport 90 liters (20 gallons) of water. It was designed for communities, particularly in Africa, where providing a household with water requires walking up to two-three hours to the nearest source and back every day. Traditionally the women and children of the communities carry out the task of getting the water. They are able to carry as much as 20 liters (5 gallons) in tanks on their heads.

The invention of the Hippo Water Roller has far reaching positive effects concerning the health of the ones carrying the water relating to the physical strain of the work. Furthermore it provides for opportunities for improved nutrition. To give an example, the roller allows people to grow food where it was impossible before due to lack of water.

The obvious practical advantages of the application of this new technology in the communities in question and its direct effect on the quality of life of its users is not, though, what is the most interesting from a social design perspective. What is particularly worth noticing from this point of view are some spontaneous side effects of the implementation of the Hippo Water Roller in the communities. When this new technology was introduced it had unexpected effects on the social dynamics. Since a new tool was available to perform the task, and it was no longer considered tedious, the men began participating. This is not a major feature of the development process in the specific communities, but it is highly interesting in connection with social design because the implementation of a simple technology has a direct effect on the social division of labor.

Another fascinating side effect of the initiative relates to an unexpected functional feature of the Hippo Water Roller itself. It was realized during the implementation of the product in Angola that in some cases it was also able to protect its users from more immediate danger. There are substantial problems with land mines in Angola. The roller was therefore tested to see if it would take the blow of a land mine exploding when encountered, since the roller is pushed in front of the person using it. All tests showed that the roller was able to protect the person behind it from the heat and shockwave almost completely. Though the Hippo Water Roller is not recommended as an anti land mine device, this is another unplanned feature of the project that is interesting in relation to social design. There is no feed back as of yet about any social implications of this additional protective function of the product (e.g. less fear in the community) but it would indeed be interesting to find out.