Mandelbrot's (1982) hypothesis that river length is fractal has been recently substantiated by Hjelmfelt (1988) using eight rivers in Missouri. The dimension of length, d , derived here from the Horton's laws network composition. This results a simple function stream and area ratios, is, = max (1, 2 log R L /log A ). Three case studies are reported showing this estimate to be coherent with measurements obtained map analysis. scaling properties as whole also investigated, network, D depend...

From the origins of hydrology, time concentration, tc, has conventionally been tackled as a constant quantity. However, theoretical proof and empirical evidence imply that tc exhibits significant variability against rainfall, making its definition estimation hydrological paradox. Adopting assumptions Rational method kinematic approach, an effective procedure in GIS environment for estimating travel across catchment's longest flow path is provided. By application 30 Mediterranean basins, it...

In recent years, flood-related risk has been increasing worldwide, being inundations among the natural disasters which induce maximum damage in terms of economic losses. research reported this paper, a methodology to map flooding residual hazard due levee failure events induced by piping embankments protecting flood-prone areas is proposed. Ensemble simulations are used account for uncertainties location, geometry, and time-evolution breaches. Probabilistic flooding-hazard maps generated...

Abstract Storage facilities are key devices in mitigating the urban drainage impact on receiving water bodies, but their design is still affected by high uncertainty. The analytical-probabilistic approach has recently raised interest, because facility performances directly related to probability. Starting from statistically independent storm events, distributions of meteorological variables must be fitted. Rainfall series, recorded three Italian raingauges, were examined for appraising two...

Abstract. In many hydrological models, such as those derived by analytical probabilistic methods, the precipitation stochastic process is represented means of individual storm random variables which are supposed to be independent each other. However, several proposals were advanced develop joint probability distributions able account for observed statistical dependence. The traditional technique multivariate statistics nevertheless affected drawbacks, whose most evident issue unavoidable...

The assessment of the efficiency a storm water storage facility devoted to sewer overflow control in urban areas strictly depends on ability model main features rainfall‐runoff routing process and related wet weather pollution delivery. In this paper possibility applying analytical probabilistic approach for developing tank design method, whose potentials are similar continuous simulations, is proved. derivation quality issues such devices were implemented. formulation based Weibull...

Flood risk assessment and mitigation are important tasks that should take advantage of rational vulnerability models to increase their effectiveness. These usually identified through a relevant set laboratory experiments. However, there is growing evidence these tests not fully representative the variety conditions characterize real flood hazard situations. This paper suggests citizen science-based innovative approach obtain information from web resources for calibration people's models. A...

Abstract Copulas are shown in this paper to provide an effective strategy describe the statistical dependence between peak flow discharge and flood volume featuring hydrographs forcing a control reservoir. A 52 year time series of discharges observed Panaro River (Northern Italian Apennines) is used fit event‐based bivariate distribution support time‐continuous modeling reservoir, located online along river system. With regard reservoir performances, method aimed at estimating return period...

Monitoring snow cover in alpine areas is important for the estimation of water storage during snowmelt season, especially view irrigation, hydropower production and supply. Cost-efliciency fine temporal resolution images from satellite-borne NOAA-AVHRR sensor indicate this source information as a suitable candidate monitoring extent. This can also be used validation distributed models. As result long-term study, ten years covered area depletion curves have been estimated using remote sensing...

Abstract. River floods are influenced by factors such as the duration, intensity and spacial distribution of precipitation land-use well morphological characteristics river basin. While tied to climatology region can change only over long term, anthropogenic land use changes exhibit a more pronounced dynamic. However, consequences on increment in flood volumes their frequency must be estimated objectively. To quantify effects urbanisation peaks Mella basin, 311 km2 size, past 50 years have...

This paper presents a simplified approach to the characterization of hydrograph following partial collapse concrete gravity dams. The proposed uses representation reservoir geometry and is based on numerical solution shallow water equations study two-dimensional evolution surface within reservoir. results are made dimensionless reorganized so as compute peak discharge, duration recession limb dam break hydrograph. practical provides quite satisfactory reproduction computed for wide set...

Abstract. In recent years, copula multivariate functions were used to model, probabilistically, the most important variables of flood events: discharge peak, volume and duration. However, in cases, sampling uncertainty, from which small-sized samples suffer, is neglected. this paper, considering a real reservoir controlled by dam as case study, we apply structure-based approach estimate probability reaching specific levels, taking into account key components an event (flood volume,...

Abstract The Mesoscale Alpine Programme (MAP) was a unique initiative to improve the understanding of processes involved in orographically influenced precipitation events and related emergence mitigation floods Alps. This study presents summary results from investigations hydrological relevance areas south (Lago Maggiore watershed) north (Ammer A special focus is given 1999 Special Observing Period (SOP) experiment. MAP has been an important dialogue platform between meteorological...

Abstract. This introductory paper presents and summarises recent research on meteorological hydrological aspects of floods in the Alps. The activities were part international project RAPHAEL (Runoff Atmospheric Processes for flood HAzard forEcasting controL) together with experiments within Special Observing Period-SOP conducted autumn 1999 Mesoscale Alpine Programme —MAP. investigations based both field numerical simulations, using models, ten major that occurred past decade European two...

The utilization of continuous approaches, namely analytical-probabilistic methods, has often been advocated for hydraulic device sizing, in order to overcome some deficiencies the design event method. In analytical distribution derivation, however, strong simplifying hypotheses are usually adopted. Rainfall depth and duration independency is most unrealistic, even if it leads satisfactory agreements between derived benchmarking distributions. reason can lie drawbacks related conventional...

Abstract Streamflow data and water levels in reservoirs have been collected at 30 recording sites the Toce river basin its surroundings, upstream of Lago Maggiore, one target areas Mesoscale Alpine Programme (MAP) experiment. These used for two purposes: firstly, verification a hydrological model, forced by rain‐gauge output mesoscale meteorological flood simulation forecasting; secondly, to solve an inverse problem—to estimate rainfall volumes from runoff mountain where influence orography...

In order to investigate the influence of soil vertical nonhomogeneity on dynamics water in upper layer, an analytical solution linearized Richards equation was derived. Here hydraulic conductivity K s at saturation is assumed decrease exponentially with depth, accordance field data reported literature and collected during our surveys mountain catchments. Gardner's constitutive laws were for retention characteristics ( ) Ψ( ). The resulting one‐dimensional linear, its coefficients depth. An...

The assumption of a particular type distribution rainfall cells in space is needed for the formulation several space‐time models. In this study, weather radar‐derived rain rate maps are employed to evaluate different types spatial organization storms through use distance functions and second‐moment measures. point patterns local maxima intensity compared completely spatially random (CSR) process by applying an objective measure. For all analyzed radar CSR rejected, indicating that at...

Abstract. In many hydrological models, such as those derived by analytical probabilistic methods, the precipitation stochastic process is represented means of individual storm random variables which are supposed to be independent each other. However, several proposals were advanced develop joint probability distributions able account for observed statistical dependence. The traditional technique multivariate statistics nevertheless affected drawbacks, whose most evident issue unavoidable...

The correct determination of the sediment yield from a basin is paramount importance in several hydraulic and environmental applications, such as evaluation storage reduction artificial reservoirs. However, due to highly episodic nature supply transport many environments extreme complexity processes involved, load river still uncertain. When time scale interest sufficiently long, when primary source comes distributed erosion watershed, problem can be tackled an indirect fashion, by computing...

A stochastic approach is developed for the determination of reduction ratio between annual maximum flow averaged over a consecutive D hour period and peak instantaneous with same frequency occurrence. Initially, crossing properties integrated process are related to those flows, using Gaussian hypothesis. The scale fluctuation river key parameter which governs theoretical function. Application made numerous historical series from Italy. To facilitate applicability model, method calibration...