The Baix Ter plain was formed by various episodes of fluvial sedimentation that occurred over time with the action of the Ter and Daró rivers.
In the lower course of the river, a calmer sedimentation was progressively dominated by less fluvial contributions. The floods of this plain by the river Ter cause wetlands to form in the last stretch of the plain.
These wetlands began to be drained in the mid-nineteenth century to take advantage of the area for agricultural and livestock activities that have formed the current agricultural mosaic, in addition they suffer a setback in the 60s due to tourism and the urbanization of the first line of the coast.
TER VELL LAGOONS
These lagoons are located behind the coastal dunes and are the result of the old mouth of the Ter, diverted in the mid-19th century. Currently they feed on the rains that are collected in the irrigation canals and that drain the cultivated fields.
During the 20th century, these lagoons received large amounts of organic material and chemical products from agriculture and sewers. In 2002, a recovery project was carried out for the entire area, removing the organic matter from the bottom and a system for collecting water from the irrigation systems where they are purified by microorganisms.
LA PLETERA LAGOONS
The lagoons of La Pletera are an area of marshes about 300 meters wide and 1 km long that suffered drainage and urbanization.
The lagoon parallel to the sea (called “laguna de la Pletera”) is located a few meters from the beach and currently, thanks to a LIFE project, it has been completely deurbanized with the intention of recovering floodplains around Ter Vell. This lagoon is used to recover an endemic fish from the Iberian Peninsula, the Fartet (Aphanius iberus), which is in danger of extinction.
The perpendicular lagoon (called “Bassa del Frare Ramon”) is an old arm of the Ter, isolated from the moment of construction of the “mota” and that maintains a natural communication with the sea
The “BASSES D’EN COLL”
They are located to the south of Ter Vell, on the other side of the river and therefore separated from the Ter Vell and Pletera lagoons. These lagoons are part of the municipality of Pals. This area has two wetlands located in parallel between the lines of the littoral dunes and the Fonollera beach.