[Individual articles from the Spring 2020 issue of Intersections will be posted on this blog each week. The full issue can be found on MCC’s website.]
In the Nzamba community of the semi-arid Ukambani region of Kenya stands a one-hundred-year-old rock-and-mortar wall built across a dry waterway. Sand has filled in behind this rock dam, which accumulates water from the rainy season’s storms. Months later in the dry season, scoop holes around the dam are frequented by residents who collect water for the household, livestock and crops. This sand dam was the oldest visited in a recent evaluation of sand dams, undertaken by MCC with its two Kenyan partners, Sahelian Solutions Foundation and Utooni Development Organization. Thousands of sand dams have been built in Ukambani since the colonial era, attesting to their potential as an elegant solution to the fundamental challenge of water supply. Thus, sand dams have a seeming permanence in the local landscape, both in the durability of the structures and in their enduring appeal to communities. However, dramatic changes have occurred in the region, and even greater climate and social changes are poised to occur over the coming years. As MCC and its local partners look back on their instrumental role in several decades of promoting sand dams, these dual questions can inform what lessons we take from these projects: What accounts for the staying power of this community-based solution to providing water? And how might projects like this stay forward-looking in the face of the accelerating shifts in climate and social structures?
The staying power of sand dams was not evident early on, as they were not universally embraced upon their initial introduction. The dam at Nzamba is characteristic of this initial skepticism and resistance: community members (especially women) who built the Nzamba dam were forced under colonial “chief’s law” to trek many days through the bush to a railhead for dam supplies. Understandably, the local Kamba people associated sand dams with colonial repression: the resistance to the sand dam was not a principled objection to the technology, but the manner in which it was imposed on the community.
For the Kenyan public’s reception of sand dams, the tide turned during a crippling drought in the 1970s, when a respected Kamba engineer suggested sand dams might alleviate the crisis. The resulting trial sand dam was so obviously effective at providing water that neighboring communities started replicating the success. Equally important was framing sand dams more as a communal activity, rather than only as a new technology. Sand dams were initiated and built by the communities themselves within the traditional mechanism of mwethya, a system of shared labor and mutual benefit. Community “self-help groups” which grew out of mwethya now form the backbone for implementing sand dams. The overarching key lesson from past sand dam success is how important adapting sand dam technology to the local context and introducing it using traditional mechanisms were vital to its widespread adoption. Only when communities were able to implement sand dams under their own terms, within the mwethya tradition, were the benefits of sand dams realized.
No development solution is static, as cultural and environmental changes alter the context in which a solution is implemented. What adjustments were critical in the past? Are sand dams equipped to meet future changes? Some adjustments to sand dams have naturally evolved. For example, communities building sand dams recognized early on that the silting of dams dramatically reduces water storage capacity. In response, sand dam projects started including terracing along the edges of the dams, thus capturing the silt. This adjustment not only improved water storage, but also provided better conditions for growing crops near the dams. Communities also discovered that building sand dams paired well with carrying out a range of associated activities, such as brickmaking and beekeeping. Kenyan organizations promoting sand dams began to do so within an integrated model of development that included income generation and livelihoods components. Intentionally including such activities expanded the range of potential benefits to communities, yet it also required a more robust degree of community organization and ongoing support. The recent MCC evaluation of sand dams found that most sand dams have water in the dry season, but that this resource is largely underutilized at many dams—livelihoods initiatives that could take advantage of this resource have not been as widely adopted as expected.
Several assessment studies have quantified the benefits and challenges of sand dams, thus raising awareness of where sand dams have fallen short of expectations. So, for example, assessments have found that sand dams have not translated into large-scale improvements in food security and that water extracted from sand dams presents a health risk due to bacterial contamination. Squaring these findings with the clear anecdotal accounts of sand dam effectiveness, and their obvious popularity with communities, remains an ongoing point of investigation. Attempts to make sense of conflicting conclusions often miss a cultural component, as assessments center around Western values of quantification and objectivity, which can be at odds with traditional African narratives and relational styles.
Central to the future of development projects such as sand dams is their ability to respond to the global climate crisis, which is shifting the very environment upon which Kamba culture and practices are adapted. Although not developed with climate change in mind, sand dams fortuitously represent a resilient response to the climate crisis. Sand dams have the potential to buffer shocks caused by shifts in rainfall patterns by increasing opportunities to collect rain when it does fall.
Less certain is how sand dams adjust to equally dramatic social changes. Sand dam promotion remains within a community-based, NGO-supported model. Efforts to incorporate sand dams into the mandate of local governments have largely failed; for the most part sand dams have not spread spontaneously in the private sector or by community financing, as was hoped. In the face of global cultural changes like moving towards privatization and away from community traditions, do self-help groups themselves have staying power, or is there another effective model of sand dam promotion as yet unrecognized? This is perhaps where observations by the sand dam communities themselves converge with development-level assessments: supporting the underlying community structures is just as important as the sand dam technology itself.
In part because of their popularity in Kenya, sand dams are now implemented in other countries such as Mozambique, Ethiopia and Chad. The degree to which sand dams can scale-up further remains to be seen, but the century-long durability of the dam at Nzamba suggests that these structures will be collecting water for decades to come.
Doug Graber Neufeld directs the Center for Sustainable Climate Solutions at Eastern Mennonite University. James Kanyari is food security field officer for MCC Kenya.
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