OR/17/007 Executive summary

Bonsor, H C, Dahlqvist, P, Moosmann, L, Classen, N, Epting, J, Huggenberger, P, Garica-Gil, A, Janźa, M, Laursen, G, Stuurman, R and Gogu, C R. 2017. Groundwater, geothermal modelling and monitoring at city-scale: reviewing European practice and knowledge exchange. British Geological Survey Internal Report, OR/17/007.

The need for cities to make more effective use of the subsurface on which they stand, is increasingly being recognised in Europe and further afield to be essential for future cities to be sustainable and more resilient, . However, city planning worldwide remains largely 2D, with very few cities having any substantial subsurface planning or Masterplans — the cities of Helsinki, Montreal, Singapore being rare exceptions, . The consequences of inadequate consideration and planning of the subsurface are far-reaching, in economic, environmental and social terms. Across Europe, poor understanding of ground conditions is recognised as the largest single cause of construction project delay and overspends. Management of urban groundwater and shallow geothermal energy resources is becoming increasingly important as cities are increasingly looking to use these resources to meet current and future energy and heating and water needs. Whilst these are, alongside potential underground building space, the two most important resources for future cities, the monitoring and regulation of these resource is widely variable across Europe.

For subsurface opportunities such as groundwater and geothermal energy to be realised and utilised to greatest effect to support growing city populations and infrastructure, city planners must be both aware of, and have some understanding of the resources, available data and research, and both the opportunities and risks which the resources provide to city development, . To supply this understanding to city municipalities and others, geological surveys must have robust datasets of groundwater and geothermal resources at city-scale, and the relevant knowledge and understanding from these data must be made accessible to inform subsurface planning in appropriate datasets relevant to different scale of interest in different planning stages. What density and frequency of data are required for a robust understanding of a city’s groundwater and geothermal resources will be different in different cities, according to the complexity of the resources, and the intensity of subsurface use and demands on the resources. Indeed, no one design of city-scale monitoring or modelling of ground-water and heat resources is appropriate for all cities, or for all monitoring objectives. However, the guiding principles of good practice for developing robust city-scale monitoring, and datasets are widely applicable, as are the key principles for ensuring these data inform city planning processes.

This report provides an initial review of existing examples of current practices in Europe with respect to groundwater and geothermal monitoring and modelling, as a resource for other cities to learn from and build upon. The report also provides an overview of some of the different practices used for communicating groundwater and geothermal energy data and knowledge to inform urban planning and management.

The Introduction of the report provides an evaluation of different good practices for generating appropriate city-scale groundwater datasets and monitoring. Urban groundwater monitoring: identifying good practice reviews the different good practices for the use, regulation, monitoring and management of shallow geothermal energy in cities. Shallow geothermal energy in urban areas provides an evaluation of different good practices for modelling groundwater and shallow geothermal resources in cities of high and low data availability. Finally, Modelling urban groundwater and geothermal resources provides a discussion as to why integration of groundwater and geothermal data into subsurface planning is still a missing link in good practices within many cities. The review provides city examples, which illustrate the guiding principles, or key points, of the different good practices discussed. The review is not aimed to be a comprehensive review of all the good practices which exist across Europe — this is far beyond the scope and resources of the review. The review instead forms an informed starting point for subsurface specialists and city municipalities wanting to learn about good practices related to groundwater and shallow geothermal data and knowledge. The Sub-Urban COST Action toolbox will provide further guidance and examples when released in 2017.