The section of the river Ebro that is under control comprises approximately 80 km, from the meander of Flix to Amposta. Upstream of Flix no control is carried out because the characteristics of the river do not favor the presence of blackfly larvae (Flix reservoirs, Riba-roja d'Ebre and Mequinensa), in the same way as downstream of Amposta, where the current is low and salinity high.
This treatment area is distributed in seven sections and a treatment point at the meander of Flix:
- Meander of Flix
- Section 1: Ascó - Garcia
- Section 2: Garcia - Gas pipeline
- Section 3: Gas pipeline - Miravet
- Section 4: Miravet - Assut Xerta
- Section 5: Xerta weir - Bítem
- Section 6: Bítem - Tortosa
- Section 7: Tortosa - Amposta
