- B1.- Pilot test of injection of sediment into the Ebro Delta irrigation network
- B3.- Optimization of the constructed green filters
- B4.- Optimization of greenhouse gases emissions in the rice fields of the Ebro Delta.
- B5.- Evaluation of the effects of sediment on rice production
- B6.- Assessment of areas vulnerable to subsidence and sea-level rise in the Ebro Delta
- B7.- Developing a Climate Action Plan of the Ebro Delta
B2.- Pilot test of injecting sediment into the final stretch of the river Ebro
B2.- Pilot test of injecting sediment into the final stretch of the river Ebro.
The construction of the Mequinensa, Riba-roja and Flix reservoirs has greatly modified the natural regime of water and sediment flows in the river Ebro. At present the amount of sediments reaching the Ebro Delta has fallen by 99%. These sediments are retained in the reservoirs and this has led to coastal regression and an increase in the subsidence rate of the Delta. These effects can be augmented by the rise in sea level caused by climate change. In this scenario, the sustainability of the Delta can only be guaranteed by restoring the transportation of sediments from the river to the sea and Delta. Sediments entering the Delta surface area and the coastal waters would generate soil (maintaining the Delta’s elevation) and halt, to a certain extent, the possible erosion of the coastal area.
The objective of this pilot action is to determine the current capacity of the river Ebro for transporting sediments (sand and clay) to the sea and the Delta surface area.
Two stretches of the river with different characteristics have been chosen: the first is at Móra d’Ebre, about 40km downstream from the reservoirs; the second is the stretch of river between Benifallet and the weir (“Assut”) at Xerta.
This pilot action will allow for the amount and typology of sediments the river can transport to be determined – dependent on different flow regimes. Theoretical models of water and sediment transportation can be evaluated. This will allow us to analyze the feasibility of designing a system to transport sediments from the reservoirs to the river, with the aim of minimizing coastal erosion and maintaining the Delta’s elevation.