puits à massif filtrant

OBS: gravel-wall well: A type of well used in a water-bearing formation containing a large proportion of fine-grained material which permits the passage of water at low velocity. Gravel is introduced around the screen or intake section of the well to increase the specific capacity and to prevent extremely fine material from flowing into the well. Depending on detail of construction, such wells are called gravel well, gravel-envelope well, gravel-filled well, gravel-packed well.