Headwater areas

Definition

Targeted planting of forests in headwater areas (e.g. with a slope) can help to stabilize hillslopes, thereby reducing erosion and potentially leading to greater water retention in montane areas. Afforestation may have beneficial effects on the hydrograph by reducing peak flows and helping to maintain base flows. The potential for water retention must be balanced against the increased ET and pollutant trapping that may be associated with forests.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission

Artificial groundwater recharge (AGR)

Definition

AGR stores large quantities of water in underground aquifers to increase the quantity of groundwater in times of shortage.ᅠ It results in a lowering of run-off from surrounding land, and in an enhanced natural condition of aquifers and water availability.ᅠ The natural cleaning process of water percolating through the soils when entering the AGR improves water quality. Mechanisms used to undertake the recharge should be highlighted. In this respect one can envisage:(i) surface structures to facilitate/augment recharge (such as soakways and infiltration basins);(ii) subsurface indirect recharge - artificial recharge is undertaken through wells drilled within the unsaturated zone;(iii) subsurface direct recharge - artificial recharge is undertaken through wells reaching the saturated zone. The regulatory approach to be adopted for each of the above three mechanisms could differ considerably, due to the fact that the level of natural protection to groundwater is vastly different for each of the mechanisms

Levelling of dams/ longitudinal barriers

Definition

Levelling longitudinal barriers allows re-establishing fluvial dynamics and ecological continuity. The aim is to restore the slope and longitudinal profile of the river, to restore natural water flows, to allow for the solid transport (sediment) to take place, toᅠ diversify flows (depth, substrate, speed), diversify habitats and related flora and fauna.
- Based on Stella definitions, adapted by NWRM project experts and validated by the European Commission