In 1939 began the construction of the hydroelectric basin for the power plant in Brixen made necessary for the electrification of the railway; the work was completed the following year and the village of Unterau was flooded.
1939. aastal alustati tammi ehitamist hüdroelektrijaamale Brixenis, mis oli vajalik raudtee elektrifitseerimiseks; töö lõpetati järgmisel aastal ja Unterau küla ujutati üle.