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- Are municipal waste utilities becoming sustainable? A framework to assess and communicate progressPublication . Fernández Braña, Álvaro; Sousa, Vítor; Ferreira, CéliaA framework of indicators to assess the progress towards sustainability of municipal waste management utilities is developed. Its purpose is to fulfil the need for assessing the performance of municipal waste (MW) management in a simple but comprehensive way—unlike indicators based on individual aspects such as recycling—and including aspects not well considered before, such as waste prevention. The framework is composed of a set of six single indicators, concerning the three dimensions of sustainability: reduction of effectively landfilled MW and reduction of MW generation (environmental component), balance between expenses and revenues and reduction of costs (economic component), accessibility to separate collection and number of complaints (social component). Each indicator consists of an evaluation of the current status of the variable in contrast to a previous situation, with a positive value in case of improvement or negative in case of decline. Then, the values of the individual indicators are combined to obtain a global result. This approach focuses on dynamic progress towards sustainability, complementing the common static indicators. Contrarily to the existing performance indicator schemes, the proposed framework aims at measuring the progress and not the absolute or relative achievement of a waste management utility. The framework was tested on two Portuguese municipalities, proving to be a straightforward application and reliable in guiding stakeholders. Results for the case study showed good performance on economic sustainability, while environmental and social performance were lower due to a lack of strategies for waste prevention and low source separation, affected by poor accessibility to separate collection.
- Evaluating and modelling a decentralised community-based waste collection system in developing São Tomé cityPublication . Fernández Braña, Álvaro; Ferreira, CéliaA small-scale waste collection service by means of a motor tricycle was put in place by the community of Boa Morte (in São Tomé e Príncipe), as a solution to face the lack of an adequate waste management in their neighbourhood. A qualitative and quantitative evaluation of the service was performed by the authors, including a characterisation of the generated waste, interviews with the population involved, a technical assessment and the development of a cost model. With respect to technical aspects, the vehicle chosen has been found to be a satisfactory choice, whereas the productivity of collection is still too low due to the dispersion of collection points. Concerning financial aspects, the cost model reveals that the scale of the scheme is still too small to be completely sustained by its own revenues, but this objective of self-sustainability is achievable within the limits defined for the system, by adding a determined number of new customers without exceeding the fixed maximum working time and introducing some improvements and time optimisation.