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This paper presents the results of a modeling study of the hypothetical dam break of Chipembe dam in Mozambique. The modeling approach is based on the software Iber, a freely available dam break and two-dimensional finite volume shallow water model. The shuttle radar topography mission (SRTM) online digital elevation model (DEM) is used as main source of topographic data. Two different DEMs are considered as input for the hydraulic model: a DEM based on the original SRTM data and a hydrologically-conditioned DEM. A sensitivity analysis on the Manning roughness coefficient is performed. The results demonstrate the relevant impact of the DEM used on the predicted flood wave propagation, and a lower influence of the roughness value. The low cost modeling approach proposed in this paper can be an attractive option for modeling exceptional flood caused by dam break, when limited data and resources are available, as in the presented case. The resulting flood-inundation and hazard maps will enable the Regional Water Management Administration of Mozambique (ARA) to develop early warning systems.

Several port authorities are involved in the R+D+i projects for developing port management decision-making tools. We recorded the movements of 46 ships in the Outer Port of Punta Langosteira (A Coruña, Spain) from 2015 until 2020. Using this data, we created neural networks and gradient boosting models that predict the six degrees of freedom of a moored vessel from ocean-meteorological data and ship characteristics. The best models achieve, for the surge, sway, heave, roll, pitch and yaw movements, a 0.99, 0.99, 0.95, 0.99, 0.98 and 0.98 R2 in training and have a 0.10 m, 0.11 m, 0.09 m, 0.9°, 0.11° and 0.15° RMSE in testing, all below 10% of the corresponding movement range. Using these models with forecast data for the weather conditions and sea state and the ship characteristics and berthing location, we can predict the ship movements several days in advance. These results are good enough to reliably compare the models' predictions with the limiting motion criteria for safe working conditions of ship (un) loading operations, helping us decide the best location for operation and when to stop operations more precisely, thus minimizing the economic impact of cargo ships unable to operate.

This article presents the methodology and results of the field survey carried out to characterise the pollution associated with the stormwater runoff from an urban catchment in Galicia (Spain). Various instruments were installed in the control section of this catchment measuring some 55 ha and located in the separate sewer system outlet, to obtain samples associated with stormwater events. In particular, precipitation and flow were recorded, in addition to the pollution associated with such flows. On the basis of this information it was possible to determine a series of pollution parameters (solids, BOD 5 , COD, TOC) and the most important event parameters (event mean concentration, maximum concentration, mobilised load per net hectare) were calculated. These results were compared with those from other similar catchments. The analysis of the results includes the determination of probability distribution as well as the study of the particle size distribution of the samples during different periods of the event, which thus enabled us to obtain the relationship between the total rainfall and the particle size distribution of each event. Finally, a study of potential best management practices using the process selection diagrams is presented.

(100-150 words) 8The understanding of the physical processes related to flows on compound meandering channels is a 9 challenge given their highly 3D and complex characteristics. Three-dimensional ADV measurements 10 were made in three cross-sections on a 1:20 physical Froude model of a real reach in River Mero (A 11 Coruña) for bankfull flow and flood conditions. General characteristics and processes within the flow 12 are herein described and characterized, such as momentum and mass exchange between the main 13 channel and the floodplains. Time-averaged velocities and Reynolds stresses are presented and 14 discussed. The spatial distribution of turbulence in several positions along a meander bend is 15 analyzed in this paper. The characterization of the turbulent field in these highly 3D complex flows 16 highly depends on the used reference system, and the intense local variation of turbulence makes a 17 global and fixed coordinate system of petty use. An independent technique, regardless the 18 coordinate system of the measurements, is thus the best way to analyse these flows. The anisotropy 19invariants technique was used to analyze the evolution of the magnitude and nature of anisotropy 20 along the meander. The degree and nature of anisotropy was identified, and their relation to flow 21 structures, such as vortices in the contact between the main channel and the floodplains, was 22 analyzed using the quadrant analysis technique. 23Keywords: meanders, compound channels, turbulence anisotropy, physical model, ADV 24 Introduction 25River management represents a challenge from an engineering, environmental and social point of 26 view. In particular, floodplains are among the most productive and diverse ecosystems in the world 27 due to the regular deposition of nutrient rich sediments (Viers et al. 2005). The environmental value 28 of these ecosystems is unquestionable given their high biodiversity and their role on water 29 purification and on the fixation of soil and nutrients. Furthermore, floodplains can be seen as natural 30 systems providing food availability and flood protection. The capacity to act as a natural protection 31 against floods is conditioned and intrinsically related to the local hydrodynamics, erosion and 32 sedimentation processes and to the global resistance of the river reach. Flow properties, more 33 specifically related to turbulent phenomena, need a good physical understanding so engineers can 34 address such important issues such as flood management, morphology evolution and spreading of 35 pollutants in river flows (van Balen et al., 2010). The physical processes underlying the formation of 36 meanders have been the subject of intensive and detailed research (i.e. da Silva, 2006; de Marchis 37 and Napoli, 2008;Stoesser et al., 2010), although the theoretical developments taking into account 38 compound meandering channels are still scarce. 39 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 ...

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Deep slot fishways (DSF) are similar to vertical slot fishways (VSF) except that a sill has been placed at the base of the slot, and thus require a lower discharge to operate. The conversion of a VSF to a DSF, which requires minimal design modifications, can make for a more flexible design in inflow management, maintaining the correct operation of the fishway in periods of limited water availability. It is, however, crucial to understand the new flow conditions that will be created inside the fishway, and their implications for fish passage. In this paper, the hydrodynamics of DSF were studied for two different pool configurations and five sill heights. The investigation comprised the analysis of the water surface configuration, the velocity and turbulence fields, as well as the definition of the equations that related discharges to depths in the pools. The DSF designs compared well in terms of water surface patterns and maximum velocities with VSFs, but resulted in a more complex three-dimensional flow pattern and increased turbulence levels. Further testing with fish is needed to analyze whether the benefits of retrofitting a VSF by adding a sill during low flows are cancelled out by increased fish passage difficulty.