Treated effluent and/or stormwater can be directly discharged into receiving water bodies (such as rivers, lakes, etc.) or into the ground to recharge aquifers. Surface groundwater recharge is the planned, man-made increase of groundwater levels. By improving its natural replenishment capacities and percolation from surface waters into aquifers, the amount of groundwater available for abstraction is increased. This is particularly useful in areas where water and groundwater resources are heavily utilised and acute problems with dropping watersheds, soil salinization, saltwater intrusion in coastal areas or water scarcity in general exist. Subsurface groundwater recharge refers to the different recharge techniques (generally injection or recharge wells) that release treated effluent and/or collected stormwater underground and directly replenish groundwater aquifers (without soil percolation).