Hydraulic risk maps provide the baseline for land use and emergency planning. Accordingly, they should convey clear information on the potential physical implications of the different hazards to the stakeholders. This paper presents a vulnerability criterion focused on human stability in a flow specifically devised for rapidly evolving floods where life, before than economic values, might be threatened. The human body is conceptualized as a set of cylinders and its stability to slipping and toppling is assessed by forces and moments equilibrium. Moreover, a depth threshold to consider drowning is assumed. In order to widen its scope of application, the model takes the destabilizing effect of local slope (so far disregarded in the literature) and fluid density into account. The resulting vulnerability classification could be naturally subdivided in three levels (low, medium, and high) that are limited by two stability curves for children and adults, respectively. In comparison with the most advanced literature conceptual approaches, the proposed model is weakly parameterized and the computed thresholds fit better the available experimental data sets. A code that implements the proposed algorithm is provided.

Highlights  The General Lake Model (GLM) is stress tested against 32 globally distributed lakes.  There was low correlation between input data uncertainty and model performance.  Model performance related to lake-morphometry, light extinction and flow regime; deep, clear lakes with high residence times had the lowest model error.

Field data, theoretical analyses, and numerical simulations were used to investigate the effects of lake basin bathymetry and spatial and temporal structures of the wind field on the basin‐scale internal wave spectrum in Lake Iseo. This deep Italian basin is characterized by the presence of a large island, imparting attributes of an annulus to the lake. During the summer of 2010, the internal wave activity was dominated by a basin‐scale internal wave of vertical and horizontal modes 1 (V1H1), superimposed on which were occasional higher vertical modes (V2H1) and higher horizontal modes (V1H5) trapped by the main island. The occurrence of these motions was interpreted as forcing by the wind components with similar horizontal structures and with energies at frequencies near the natural oscillations of the excited modes. The modifications of the wind field by the topography, in particular, controlled the excitation of an anticyclonic wave trapped around the island, whose features were investigated on the basis of an extension of the circular model to the case of an annular basin of constant depth.

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On the morning of December 1, 1923, the Gleno Dam (located in the Central Italian Alps) suddenly collapsed a few days after the first complete reservoir filling. Nearly 4:5 × 10 6 m 3 of water was released. The consequent inundation caused significant destruction along the downstream valley and a death toll of at least 356 lives. This failure is the only historical case of dam break caused by structural deficiencies that has occurred in Italy. As a result, it has deeply influenced the evolution of Italian regulations regarding dam design and hydraulic risk evaluation. However, in spite of its relevance, this event has never been characterized from a hydraulic standpoint. This paper reports the main information obtained from the analysis of a vast amount of historical documents regarding the Gleno Dam break to set up a case study useful for validating dam-break models in mountain settings. Moreover, it presents the main results of one-dimensional (1D) modeling of the dam break wave propagation accomplished with a first-order finite volume numerical scheme recently proposed in the literature for field applications. The overall effectiveness and reliability of the model are evaluated for this case characterized by very irregular topography. Finally, the practical relevance of several choices that the numerical reconstruction of this kind of event demands is tested.