The outflows of the Po River in the city section between the Carignano bridge and San Mauro Torinese (about 32 km) were studied in the different hydraulic conditions of opening of the retention structures by means of a 2D Numerical Hydraulic Model that simulated the different scenarios for flows related to return times of 200 and 500 years.

The calibration of the Numerical Model followed the following steps:

• integration of historical topographic data with a campaign of GPS surveys georeferenced with Digital Terrain Models (DTM) provided by the Ministry of Environment, with the inclusion of all city bridges;
• setup and calibration of the 2D hydraulic model through a back-analysis process of the 24-25 November 2016 event, using the observed hydrograms of the Po river at Carignano, Moncalieri and Murazzi, as well as the data of the tributaries Banna, Chisola, Sangone, Dora Riparia and Stura di lanzo;
• definition of the verification flow rates Tr 200 and Tr 500 at the La Loggia dam and at the Pascolo dam in San Mauro;
• simulations of 3 different configurations of dam floodgates closure:
  • Scenario 01: fully closed floodgates;
  • Scenario 02: 50% closed floodgates;
  • Scenario 03: open floodgates.