modern old derivation
Laque Lake Small stream Flemish
Lawe - -
Lietle - -
Liane Elna Marshy
Lys Lewia liga, "sediment"
Marque Marko Marshy - Germanic
Pernes - -
Planquette Capriuno -
Rhonelle Rod red - Indo-European root
Sambre Samera Sam = "peaceful" +pre Celtic suffix "ara"
Selle Sabis -
Sensée - -
Slack - -
Solre - -
Somme Samaro Su|mena = "very|peaceful"  
Ternoise Terna -
Tournes - -