Managed Aquifer Recharge: An Overview of Issues and Options

Abstract

As covered in Chap. 2, many of the world's aquifers are rapidly being depleted. Nearly one quarter of the world's population -1.7 billion people -live in regions where more water is being consumed than nature can renew (Gleeson et al. 2012). Over-exploitation occurs when groundwater abstraction is too intensive, for example for irrigation or for direct industrial water-supply like extracting fossil fuels Foster et al. 2013). When groundwater is continuously over-pumped, year after year, the volume withdrawn from the aquifer cannot be replaced by recharge. Eventually, the groundwater level is much lower than its initial level and even when pumping stops, the aquifer has trouble rising once again to its original level. In continental zones, overexploitation can lead to groundwater drawdown and, ultimately, to subsidence through development of sinkholes when underground caverns or channels collapse. In coastal areas, the decrease in groundwater recharge results in saltwater intrusion into the aquifer formation (Petalas and Lambrakis 2006;De Montety et al. 2008). Preserving local groundwater resources is an environmental and economic issue in coastal zones and is vital in an island context. The increasing demand for water caused by a growing population can lead to the salinization of groundwater resources if these are systematically over-exploited. Limiting the salinization of coastal aquifers is consistent with the groundwater objective of the European Union Water Framework Directive, which is to achieve a good qualitative and quantitative status by 2015. The economic advantage of preserving these threatened water resources is that, when there is a growing demand, a local water resource is sustained and there is no need to import water. Transporting water can cost 2-10 times more than limiting the intrusion of saltwater into a coastal aquifer.

Application of numerical models to assess multi-source saltwater intrusion under natural and pumping conditions in the Great Maputo aquifer, Mozambique

“…Currently, the operation by private water providers for peri-urban and rural water supply fits well to the hydrogeological conditions and should be promoted. Management strategies to prevent future water supply shortages and mitigate salinity impacts should consider the use of managed aquifer recharge (MAR) methods for its proven efficiency (Cassanova et al 2016;Dillon et al 2019). The constructed models can be used to assess the feasibility of MAR application in the Great Maputo area.…”

Fluoride and phosphate release from carbonate-rich fluorapatite during managed aquifer recharge

“…Globally, but especially in arid and semiarid regions, managed aquifer recharge (MAR) is an increasingly used water management tool. It involves infiltration or direct injection of water into suitable aquifers to improve and secure long-term water supplies (Casanova et al, 2016;Dillon and Arshad, 2016). In most applications of MAR, the infiltration or injection of various water types (e.g., surface water, purified wastewater, stormwater runoff) typically creates a geochemical disequilibrium that triggers a wide range of water-rock interactions (Descourvieres et al, 2010a;Fakhreddine et al, 2015;McNab Jr et al, 2009;Treumann et al, 2014;Vanderzalm et al, 2010;Wallis et al, 2011).…”

Institutional Feasibility of Managed Aquifer Recharge in Northeast Ghana

“…Therefore, it behooves MAR operators to consider these before initiating MAR projects. Like Casanova et al [45] noted of France, and Megdal et al's [46] discussion of the USA state of Arizona, Ghana's laws/legislation, to some extent, are explicit on the requirements that need to be met in order for MAR to be accepted. When compared with policies and administrative agencies/organisations, it can be concluded that the relevant existing laws provide better and more comprehensive information for MAR activities in the country, and failure to comply with them may result in the rejection of MAR projects.…”