Urban surfaces reflect the economic, environmental and social idiosyncrasy of cities, playing a crucial role in the sustainable development of modern civilizations. Thus, the planning and efficient management of the skin of urban areas provides an opportunity to facilitate the fulfilment of the needs of present and future generations. However, there is a lack of specific tools to evaluate the contribution of these surfaces to achieving the Sustainable Development Goals (SDGs), which is the current framework adopted by the United Nations to measure progress towards sustainability. Consequently, this paper describes the design and application of a Sustainable Urban Surface Rating System (SUR-SIST) aimed at producing a composite sustainability index to measure the contribution of the land cover of entire cities to meeting the SDGs. SURSIST was based on a series of indicators proposed in accordance to the targets forming the SDGs, which were processed by combining CORINE Land Cover (CLC) maps with the Analytic Hierarchy Process (AHP) and the Technique for Order of Preference by Similarity to Ideal Solution (TOP-SIS). The application of SURSIST to the Spanish cities of Santander and Valencia during the time period from 1990 to 2006 demonstrated the progressive decrease in sustainability experienced by their urban surfaces due to the increased presence of impermeable covers. The replacement of a moderate part of the built-up area present in both cities in 2006 by greenspace proved to be a solution for recovering the degree of sustainability lost from 1990.

This research aimed at ascertaining the performance of raw dura species of Palm Kernel Shells (PKS) in comparison to a different species of PKS (tenera) as a replacement for known aggregates for pervious lightweight concrete. Using limestones as the known aggregates, control pervious concrete was batched, and relevant tests were conducted. Major tests conducted on the composites concerned compressive, tensile, and flexural strength, as well as permeability, densities, and absorption. Logistic constraints on transporting the dura-PKS limited the quantity needed to ascertain the variety of replacements of the dura-PKS. With a 25% replacement known to be the most suitable ratio for related investigations, we adopted that ratio and compared to the extreme ratio of 100% dura-PKS. The tests revealed that a 100% replacement of known aggregates by the dura-PKS resulted in high porosity and permeability, although the resistances to compression, tension, and flexural loads read low for the same mixture. Instead, pervious concrete 25% of dura-PKS replacement yielded optimum water permeability rate and flexural and compressive stresses. However, the flakiness index recorded for the dura-PKS was almost half that of the tenera species and was not reflected in the mechanical properties as the results gave relatively lower strengths. The results in the case of the dura species do not differ significantly compared to the tenera-PKS in terms of strength and permeability.

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