The river's waters are accumulated in the Ulldecona dam, also located in the same municipality at an elevation of 477 meters above sea level.

This reservoir, with a surface area of 116 hectares and a capacity of 11 hm³, is the only infrastructure regulating the river and is used for irrigation.

From the reservoir, the river passes through areas with steep slopes, which provide it with high oxygenation.

Further downstream, before reaching the homonymous municipality, water diversions are made to supply irrigation for an area of approximately 2,360 hectares.

As it moves away from this point, the river practically receives no natural contributions, and the water quality deteriorates significantly.

llamado del Abad, en donde hay un puente de madera; 1/2 hora mas abajo á la der.

de Tortosa), desde cuyo momento toma este nombre que conserva hasta su desagüe.