ABSTRACT
In this paper, we report results from, and demonstrate the value of, a global database for the collection and aggregation of reliable and comparable cost data for urban sanitation systems as they are built and operated on the ground (rather than the "as planned" costs that are often reported). We show that no particular "mode" of urban sanitation (for example "sewered sanitation" or "fecal sludge management") can be meaningfully described as "low cost" when compared to other modes. We show that economies of scale may operate for systems that transport waste from pits and sealed tanks by road as well as for sewerage. We use a case study example to show the value of being able to compare local costs to global benchmarks and identify that operational considerations such as low connection rates may be more significant in determining overall cost liabilities for urban sanitation than technical considerations such as population density, size, and degree of centralization/decentralization.
Subject(s)
Sanitation , Sewage , Sanitation/methods , FecesABSTRACT
A majority of the world's population use onsite sanitation systems, which store or treat excreta close to where it is generated. Sludge from these systems needs to be managed through a series of stages, known as the sanitation value chain. There is a huge diversity of service providers, not only within each part of the chain, but also along the chain bridging the different components. These service providers are linked not only by the flow of materials, but also by the transfer of money. Therefore for this system to be considered financially sustainable all services from the toilet to reuse or disposal need to be considered. A tool has been developed (eSOSView™) to simulate, evaluate, and optimise the financial flows along and within the sanitation value chain. In this paper eSOSView™ was tested, validated (using existing data), and piloted (including data collection). This paper demonstrates how eSOSView ™ can be used to evaluate different financial flow models, to assess financial sustainability in different parts of the sanitation value chain and optimise the financial sustainability along the sanitation value chain.
Subject(s)
Sanitation , SewageABSTRACT
Ultraviolet germicidal (short wavelength UV-C) light was studied as surface disinfectant in an Emergency Sanitation Operation System(®) smart toilet to aid to the work of manual cleaning. The UV-C light was installed and regulated as a self-cleaning feature of the toilet, which automatically irradiate after each toilet use. Two experimental phases were conducted i.e. preparatory phase consists of tests under laboratory conditions and field testing phase. The laboratory UV test indicated that irradiation for 10 min with medium-low intensity of 0.15-0.4 W/m(2) could achieve 6.5 log removal of Escherichia coli. Field testing of the toilet under real usage found that UV-C irradiation was capable to inactivate total coliform at toilet surfaces within 167-cm distance from the UV-C lamp (UV-C dose between 1.88 and 2.74 mW). UV-C irradiation is most effective with the support of effective manual cleaning. Application of UV-C for surface disinfection in emergency toilets could potentially reduce public health risks.
