Hydrological and hydraulic studies to assess dam safety

Background

The artificial reservoirs are fundamental for water resources management, by regulating releases to meet the different users request (industrial, irrigation, hydropower, etc.), and for downstream territories floods defence through lamination of critical flood waves.
The main objective of the project concerns the review of hydrological-hydraulic studies carried out for the Montedoglio dam, on Tiber River, Casanuova dam, on Chiascio River, Sovara dam on the Sovara stream and Calcione dam on the Foenna stream. Moreover, the outlet release curves were identified for Casanuova reservoir and then revised to take account of works carried out to maintain the dam functionality.

Purpose

  1. to verify the hydrologic-hydraulic safety of dams managed by EIUT;
  2. to identify the release curves, i.e. the relationship between released discharge, height of the artificial lake and opening of the gates.  ).

Methods

the assessment of the hydrological-hydraulic safety of dams managed by EIUT was carried out through a procedure based on three steps:

1) analysis and comparison of methods for design discharge assessment;

2) application of conceptual hydrological modelling for estimating the design hydrograph for return period of 1000 years;

3) assessment of lamination effects of the reservoirs on flood hydrographs with different return periods.

For release curves assessment, simplifies techniques (energy line, hydraulic grade line, Torricelli’s formula) were considered, whose results were compared with those provided by the application of a non-stationary, one-dimensional hydraulic model.