Reservoir silting up is a particularly serious phenomenon in a climate change scenario, where rainfall is more irregular and droughts more prolonged, and in a global change scenario (with the application of aggressive agricultural techniques that deplete agricultural soils and make them more vulnerable to erosion):
The basic functions of a reservoir, which are the regulation of the hydrological regime of a watercourse and the storage of water for use during periods of drought and by various economic agents, are severely diminished if its capacity is drastically reduced.
Therefore, it is It is imperative to understand this phenomenon in order to stop and solve it.
This is especially true in regions like the Algarve, which, like many others on the Atlantic coast, has tourism as its main industry (Blue Economy) and, consequently, depends heavily on water availability.
Nature-based solutions will be designed to reduce erosion and sediment runoff into the reservoirs: installing sensors and conducting hydraulic studies to determine the origin of the inputs to both reservoirs during floods, when much of the water and sediment comes not from the main rivers, but from secondary tributaries.
Likewise, innovative solutions will be designed to assess the usable capacity of the reservoirs through the application of underwater LiDAR to show bathymetry and determine the volume of accumulated sediment, in order to evaluate possible solutions for removing existing sediment sustainably and minimizing the carbon footprint, as well as maintaining “ecological flows”:
Discharge is a fundamental management mechanism and It must comply with the provisions of the Water Framework Directive 2006/60, which requires a Hydrological and Environmental Study for each river to determine the minimum flow necessary for the river to maintain its functions and ecosystems in good condition.
