Towards an evidence base for groundwater data investments

There is global consensus among scientists and policymakers that the scarcity of high-resolution water monitoring data remains one of the most fundamental bottlenecks to sustainable water resources management (WRM). However, a lack of local valuations or clear practical pathways for monitoring implementation often hamper their case for investment. Here, by means of 42 expert interviews, we map the benefits of groundwater data to 18 identified user-groups in the data-scarce Horn of Africa, which monitors the availability and quality of the region’s primary clean water source. We then assess the outstanding barriers to monitoring and expert recommendations for practical solutions. We find that groundwater data can support systemic changes in WRM towards evidence-based, proactive and decentralised decision-making, and the data holds further value to emergent user groups in agricultural, industrial, humanitarian, political and financial sectors, most notably providing a more robust evidence-base for financing WRM projects. Experts identify manifold implementation barriers, for which their recommended solutions are summarised in a 5-stage implementation framework for sustainably scaling decision-integrated groundwater monitoring systems. Application of the framework’s recommended practices can reduce the investment risk of monitoring networks failing to realise their expected benefits to users. We recommend replication of this study’s qualitative approach for other hydrological variables and situational contexts, as well as further development through quantitative value propositions, as these are important pre-steps to attracting investments and ensuring that future monitoring implementations are optimised to user requirements. • Groundwater monitoring has potential value to 18 Horn of Africa user-groups. • Groundwater data enables evidence-based, decentralised water resource management. • The data holds further value to finance, agriculture, industry, aid and research. • Experts identify manifold reasons for current data scarcity and recommend solutions. • Other hydrology variables and contexts require similar studies to attract investors.