translate English to French: Sewer separation, however, is an extremely expensive way of solving the combined sewer problem, and it creates an additional stormwater problem in the process.
La sÃ©paration des eaux des Ã©gouts unitaires, cependant, est une solution trÃ¨s coÃ»teuse et donne lieu Ã un surplus d'eaux pluviales Ã traiter.