The study of Diptera of medical importance in areas affected by dam constructions is very important due to the possibility of the occurrence of diseases transmitted by these species. Collections were performed during 2010 and 2011 in an area under impact of a dam on the Uruguai River in the borderland of Rio Grande do Sul and Santa Catarina states. Insects were collected using suction tubes and Shannon trap, also immature live forms were obtained by manual collect. Eight-hundred sixty-one Diptera insects were captured, including Haemagogus leucocelaenus (Culicidae), Aedes albopictus (Culicidae), three species of Anopheles spp. (Culicidae), two of Plebotominae and three distinct Simuliidae species. The Diptera fauna in the area is diversified and species with medical importance were identified before and after reservoir filling.
dams; Diptera; environmental impact; vectors