An epidemiological survey was made on the inhabitants of 23 artificial dams constructed by D.N.O.C.S., Northeastern Brazil. Nine autocthonous cases of schistosomiasis were found in irrigated areas located in São Gonçalo (state of Paraíba) where this endemic disease was already known. Other two cases were found in the irrigated area of Moxotó (state of Pernambuco).