David Lentz

The New Urban Agenda’s call for long-term visions in urban planning fails to recognise that ‘long-term’ implies different longevities depending on context of assessment. Compared to other social sciences, archaeological approaches add rigour to envisioning urban sustainability over several centuries and millennia. The archaeology of the pre-Columbian Lowland Maya urban tradition is an interesting case because data have been used to support conflicting arguments about Maya urban sustainability. We suggest that these contradictions can be partly explained by: (1) sustainability being ambiguously defined, (2) subsets of the urban system being expected to indicate the behaviour of other subsets or of the entire system, and (3) processes being evaluated using different timescales. Drawing on 1500 years of urban history at Tikal, this paper examines how archaeological perspectives add depth of reflection and unfold critical assumptions of the meaning of ‘long-term’ and ‘sustainability’ concealed in self-explanatory notions. We outline the development and longevity of urban settlement at Tikal and analyse the blue-black-green (water, soil, vegetation) infrastructures that sustained urban metabolism and sponsored basic urban functions. Our analyses contribute new insights on the challenges associated with future sustainability transitions over varying temporal scales. The diversity of past and present urban systems and infrastructural initiatives cannot be fitted within a single narrative of urban sustainability, however, and much research is required to examine how blue-black-green infrastructures can support transformative change of aggregated human population zones struggling with potable water scarcity, soil degradation, and habitat and biodiversity loss.