Rewilding Gredos

Water Harvesting

Water harvesting brings together a range of techniques designed to slow and redistribute runoff, allowing part of the rainwater or snowmelt to infiltrate gradually into the ground. Instead of letting it flow rapidly down streams and slopes, the water is guided through small channels, ditches, or permeable structures towards areas where it can soak into the soil. Water “sown” during the wet months then moves slowly through the subsurface and may reappear later in springs, fountains, and watercourses. Traditional systems such as the acequias de careo of Sierra Nevada have used this principle for more than a thousand years to recharge aquifers and extend water availability through the dry season.

Applied carefully in the mountain savanna, this practice could help retain soil moisture for longer, sustain grasslands, ponds, and small wetlands, and improve the vegetation’s resilience to increasingly severe droughts. Mountains also play an essential role in groundwater recharge: they receive more precipitation and feed springs and water flows that support ecosystems and communities at lower elevations. A recent study on the nearby slopes of La Vera highlights precisely the importance of mountain groundwater in sustaining rivers and supplying the outer areas of the valley. For this reason, we want to explore, together with specialists and public authorities, whether small-scale interventions could help retain some of the water that currently runs quickly off the slopes. If carefully planned, water harvesting could benefit both the savanna and the communities and farms downstream that depend on springs, mountain streams, and aquifers. The aim would not be to alter natural watercourses indiscriminately, but to restore the landscape’s capacity to slow, absorb, and store water through pilot projects subject to hydrogeological assessment, administrative authorization, and scientific monitoring.