Jean Alan Sipra says; "Louis Fédié, whose erudition is a measure of intellectual honesty, is the author of interesting monographs on localities within the Razés, which include Espéraza. He contends that the original village was located downstream of the current location, in the district of Garnaud. To be sure, he asked the engineers responsible for the construction of the railway Carcassonne-Quillan, 1875, to report to it any remains they might encounter in this area. Pickaxes and navvies actually brought to light, in a place called Garnaud, substructures of buildings buried underground.
Historically, Ecclesiae Sanctae Mariae Asparazanus was founded by the Abbey of Alet, who had herself been endowed in 812 by Count Bera. The first document mentioning the religious establishment date of 1015. Thereafter, a village was established around the church and its history can be traced until 1145. After that date, according to Fédié, the town disappears and rebuilt upstream;, ie at its current location, at an unspecified date. He attributes the destruction to the Crusade, memory loss, which devastated the region in the summer of 1210. In fact there seems to be a period, troubled and uncertain, in which the town of Sparazan completely disappears for unknown causes And, for reasons that are not understood, it was not rebuilt in its original location, around the church, but largely upstream! It may seem discourteous to doubt Fédié conjecture, but it justifies an adverse comment. If the northern barons had destroyed the town and the castle, they would have been careful not to touch the church and church property! So there would have been no reason for that, those inhabitants who had escaped during the invasion, not to rebuild their houses around the church on their return. If they have not done is simply because it did not exist!
In fact, it seems that the whole town, including the church, had disappeared at a difficult time to identify, but without doubt before 1145. In the logic, it seems that a sudden natural disaster could have happened rather than human intervention, because the village suffers complete annihilation. The fact that the location of the original town is situated exactly in the vallée de Couleurs that significant substructures were found in the mud of the place, are clues to consider. A second index of the last occurrence of a natural disaster is the fact that there existed before, in the town of Espéraza, ponds whose presence is reported in le dictionnaire topographique de l'Aude de l'abbé Sabarthès. Without prejudice to their location in the basin since they disappeared, they could be a residue, and thus the "signature" of an ancient flood. As for the possible date of the disaster; if we reference the history of Carcassonne of Fédié, we learn that the year 850 was called, in the lowlands, one of the flood!"
Below is a pic. of ancient Garnaud and its placement geographically. Is it possible that the ancient Esperaza was washed away by flood?