Stream bed stabilization using boulder check dams that mimic step-pool morphology features in Northern Italy

During the last 10 years, the check dams made of boulders have been fully employed for torrent management, particularly for high-gradient stream stabilization. The analysis of this typology is shown in relation to three aspects: building features, field of use and design according to geomorphologic principles. The "Maso di Spinelle" torrent located in the Province of Trento, Italy (North Italian Alps) is an example where a sequence of low-check dams made of boulders have been used for bed stabilization. The design criteria are taken from the step-pool morphology features and the results are encouraging for further applications. The artificial step-pool grade-control structures in the Maso di Spinelle torrent have been successfully tested by floods events with return periods of about 7-10 and 20-25 years. (C) 2002 Elsevier Science B.V All rights reserved.