Hello again,

Sorry for the answering delay, I was off home for several days.

As you said, "Bolès" is indeed more frequent in French context because unfortunately in France the Catalan language has very scarce official recognition and the general toponymia still lacks of authorised control. The French administration switched three centuries ago all the Catalan names to French, which is the unique official toponym for many of them, and this deturpation in the correct spelling when recovering the original Catalan names is still problematic nowadays due to sociolinguistic issues such as minorisation and diglossia.

The name Bulès comes after the village Bula, as explained by ethymologist and linguist Dr. Joan Coromines in the Onomasticon Cataloniae (free access: https://oncat.iec.cat/veuredoc.asp?id=11213). The same is stated in the Nomenclator approved by the Northern Catalonia's University in Perpinyà, which I linked in the previous message. Hence, in Catalan it should be written Bulès, no matter if the French administration is mispelling the name even when trying to write it in Catalan...

All things considered, adding a "local name" which is not the original Catalan one (el Bulès) nor the official French deturpation (le Boulès) will turn the case even more confusing as it already is!

Anyway, thanks for your kind answer and your help (I'm new in OSM and did'nt know I wasn't changing the name of the whole waterway).

Salut!