Embedding sustainability criteria into pre-appraisal of underground utility for future cities

The underground utility infrastructure (UUI) will play a crucial role in meeting the demand for creating sustainable and resilient urban developments that are fit for purpose today and in the far future. The utility streetworks operations, an important feature of the UUI system, include placement, maintenance, rehabilitation, renewal and upgrading of UUI, which can have adverse economic, social and environmental impacts. A key challenge, and one that will lead to lost opportunities for the best use of the near surface for utility provision for future cities, is the lack of a sustainability indicator system and assessment method for evaluating different utility streetworks solutions. To address this shortfall, this paper presents a new suite of indicators, or performance criteria, bespoke to utility streetworks projects as well as a pre-appraisal method based on the adaptation of the Arup SPeAR® sustainability evaluation framework. An example of the application of the modified system is provided for a trenchless against trenching case study, and the lessons that flow from this are discussed in the wider context of the synthesis of utility service operations into sustainable, resilient, smart and liveable cities of the future.