Browsing by Author "Ferguson, Charlie"

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    Data supporting the paper: "An evaluation of different provision strategies for scaled-up container-based sanitation"
    (Cranfield University, 2021-09-22 11:58) Ferguson, Charlie
    This dataset underpins the paper entitled: "An evaluation of different provision strategies for scaled-up container-based sanitation". It contains:(1) Five python scripts. The first two deal with the geo pre-processing of data and construction of the distance matrix for each network. The third contains the script used for CBS provision Strategy A. The fourth contains the script used for CBS provision Strategy B. The fifth contains the script used for CBS provision Strategy C. (2) Spatial data (all in local UTM co-ordinate reference systems) for: the identified buildings in each of the four neighbourhoods, the CBS collection depots used for CBS provision Strategy A and the CBS transfer stations used for CBS provision Strategy C.(3) An excel file containing the primary results of the paper (averaged driving and walking distances).
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    ItemOpen Access
    An evaluation of different provision strategies for scaled-up container-based sanitation
    (IWA Publishing, 2021-09-17) Ferguson, Charlie; Mallory, Adrian; Hutchings, Paul; Remington, Claire; Lloyd, Erica; Kiogora, Domenic; Anciano, Fiona; Parker, Alison
    Container-based sanitation (CBS) is increasingly used to provide safely managed sanitation in low-income urban settlements. However, questions remain around the viability of scaling up the technology, partly because it relies on regular emptying and servicing of containers by a CBS provider. This paper investigates mechanisms by which this process can be achieved efficiently. Three separate collection strategies are evaluated for their routing efficiencies as CBS goes to scale. An open-source route optimisation solver determines the constituent driving and walking distances necessary for each strategy and has been applied in areas of Cape Town, Cap-Haïtien, Lima and Nairobi. The results indicate that with fewer users (e.g. 50) transfer station models offer the shortest driving routes. However, these do require users to carry their containers (e.g. up to 170 m when stations are 100 m apart). As the number of users increases (e.g. to 5,000), visiting individual houses from a neighbourhood depot offers increasingly efficient driving distances. Overall, however, the results suggest that economies in collection distances for scaled CBS will be largely conditional on greater vehicle capacity (rather than any particular provision strategy). This highlights the importance of road access throughout low-income urban settlements in providing a viable CBS service at scale.
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    ItemOpen Access
    A qualitative study on resource barriers facing scaled container-based sanitation service chains
    (IWA Publishing, 2022-02-22) Ferguson, Charlie; Mallory, Adrian; Anciano, Fiona; Russell, Kory; del Rocio Lopez Valladares, Hellen; Riungu, Joy; Parker, Alison
    Container-based sanitation (CBS) is an increasingly recognised form of off-grid sanitation provision appropriate for impoverished urban environments. To ensure a safely managed and sustainable service, a managing organisation must implement a service chain that performs robustly and cost-effectively, even with an expanding customer base. These ‘CBS operators’ adopt varying approaches to achieve this objective. Following research including interviews with representatives from six current CBS operators, this paper presents a generalised diagrammatic model of a CBS service chain and discusses the three broad thematic challenges currently faced by these organisations. Supplying cover material is a universal problem with hidden challenges when taking advantage of freely available resources. There is no universally applicable approach for the efficient collection of faecal waste despite the high labour costs of waste collection. The best strategy depends on the CBS operator's overall expansion strategy and the location of fixed features within the served community. Although CBS is technically well-suited to being turned into new products within the circular economy, in practice, this requires a diverse range of skills from CBS operators and is hampered by slow growth in other organic waste recovery services and unhelpful regulation.