Mittersill starts flood works to more than triple retention capacity

Flood protection work has begun around Hintersee, near Mittersill, with a new retention basin set to hold about 700,000 cubic metres of water, more than three times the current capacity, ORF Salzburg reported.

The project on the Felber Ache stream includes a 70-metre earth dam and a 10-metre concrete barrier. The existing barrier, built in the 1970s, is being removed. The expanded basin will increase capacity from 200,000 to around 700,000 cubic metres and is expected to reduce water discharge by about 20 per cent during a once-in-a-century flood.

The works are expected to continue until November 2027 and cost around 2.7 million euros. The state of Salzburg is covering 90 per cent of the bill, with the remainder funded by the Salzach-Oberpinzgau Water Association.

Construction is taking place in the edge zone of Hohe Tauern National Park. Project officials said ecological oversight had been included to ensure environmental requirements are met.

A separate flood-retention project in Hollersbach has been approved, but it cannot start until it receives funding from the federal government.