Karst knowledge exchange to improve protection of groundwater resources

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Karst processes involve the dissolutional enlargement of fractures within rock to produce voids through which groundwater flow is extremely rapid. Karst occurs in all rocks that are susceptible to dissolution and results in rapid subsurface pollutant transport (several kilometres per day) and flow patterns that are difficult to predict. Understanding where rapid groundwater flow occurs is key to understanding permeability, storage, and pollutant migration, which is essential for all aspects of groundwater management, and for complying with EU water regulations. In the UK, whilst the occurrence of karst is well recognised in the Carboniferous Limestone, this is not the case in the younger carbonate aquifers (the Chalk, the Jurassic Limestones and the Permian Limestones), where spatial variability in rapid groundwater flow is not well characterised, and groundwater managers have poor access to information on karst. This fellowship will focus on these younger carbonate aquifers where knowledge is not well developed. The aims are to use knowledge exchange to raise awareness of karst in these aquifers, and to bring together data and knowledge from research and industry to develop tools to improve aquifer management and protection. The rationale is that better knowledge of rapid groundwater flow will improve many aspects of catchment management including ensuring good water quality status, managing pollution events, managing discharges to groundwater, management of safeguard zones, and protection of groundwater resources. Karst data will be compiled from many organisations in industry and academia. Data that will be collated include: geological data (because the geological setting influences karst development); geomorphological data (which provides direct evidence of karst), information on subsurface karst features encountered in engineering and construction projects (because these hidden karst features have no surface expression, and engineering experiences provide a different source of information on karst development); tracer testing data (which provides direct evidence of rapid groundwater flow, sometimes over several kilometres); information from pollution events (e.g. where pollution of an abstraction borehole or spring was proven to be from a source some distance away); information on turbidity in abstraction boreholes (because this is known to be an indicator of karst processes). These data will be used to develop a map showing domains with different levels of karstification and risk of rapid groundwater flow, which will provide evidence to inform and support decision making. In addition web based karst resources will be created to enable managers and decision makers to easily access local data and knowledge on karst in different geographical areas. These will include links to papers and reports, data, text summarising karst in the area, and information on people with experience of karst in the area.The knowledge-exchange process will involve meetings with regulators, water providers and consultants to compile data, and to discuss the methodology and format of the karst domains map and the web based karst resources to ensure that they are designed to maximise their effectiveness and impact, and their uptake by other stakeholders. The meetings will include discussions of issues that arise due to rapid groundwater flow and there will be flexibility to pursue these, for example by bringing together experts to develop new strategies in response to stakeholder concerns. Workshops will be held to determine how karst data can be best used for management and protection of groundwater resources, with topics focused on stakeholder requirements. Overall this knowledge exchange will enable the development of tools and knowledge to greatly improve management and protection of groundwater resources, which will be based on a world leading understanding of karst, and will have economic and environmental benefits.