Discrete Phase Modelling of Sediment Transport and Scouring of Suspended Particles in Dam Spillway

One of foremost issue arise in the dam management and dam reliability assessment is the sedimentation of suspended particles. Sedimentation affected the energy production and efficiency, storage, discharge capacity, and flood attenuation capabilities. In this paper, the sediment transport and scouring in the dam spillway structure was modelled using finite volume method (FVM) based software, ANSYS. The trajectory of suspended particles in the water flow was formulated based on the discrete phase model (DPM). To access the simulation model, particle image velocimetry (PIV) experiment using scaled-down dam spillway model was conducted. The discrepancy between the findings attained from simulation and PIV experiment is less than 4.89%, inferred the numerical model was acceptable. It was found that the maximum scouring rate and maximum deposition rate are respectively 4.20×10−9 kg/s and 2.00×10−6 kg/s. As such, it was empirically approximated the dam maintenance should be scheduled once every 8.9 years, based on sole consideration on resolving the scouring and deposition of suspended particles. This work demonstrated the viability of DPM based numerical simulation in study the fluid-particle interaction of sediment transport problem, particularly for the application of dam reliability.

Flood-Rings Production Modulated by River Regulation in Eastern Boreal Canada

In northeastern boreal Canada, the long-term perspective on spring flooding is hampered by the absence of long gage records. Changes in the tree-ring anatomy of periodically flooded trees have allowed the reconstruction of historical floods in unregulated hydrological systems. In regulated rivers, the study of flood rings could recover past flood history, assuming that the effects of hydrological regulation on their production can be understood. This study analyzes the effect of regulation on the flood-ring occurrence (visual intensity and relative frequency) and on ring widths in Fraxinus nigra trees growing at five sites distributed along the Driftwood River floodplain. Driftwood River was regulated by a dam in 1917 that was replaced at the same location in 1953. Ring width revealed little, to no evidence, of the impact of river regulation, in contrast to the flood rings. Prior to 1917, high relative frequencies of well-defined flood rings were recorded during known flood years, as indicated by significant correlations with reconstructed spring discharge of the nearby Harricana River. After the construction and the replacement of the dam, relative frequencies of flood rings and their intensities gradually decreased. Flood-ring relative frequencies after 1917, and particularly after 1953, were mostly composed of weakly defined (less distinct) flood rings with some corresponding to known flood years and others likely reflecting dam management. The strength of the correlations with the instrumental Harricana River discharge also gradually decrease starting after 1917. Compared with upper floodplain trees, shoreline trees at each site recorded flood rings less frequently following the construction of the first but especially of the second dam, indicating that water level regulation limited flooding in the floodplains. Compared with the downstream site to the dam, the upstream ones recorded significantly more flood rings in the postdam period, reemphasizing the importance of considering the position of the site along with the river continuum and site conditions in relation to flood exposure. The results demonstrated that sampling trees in multiple riparian stands and along with various hydrological contexts at a far distance of the dams could help disentangle the flooding signal from the dam management signal.

Comparison of Seasonal Flow Rate Change Indices Downstream of Three Types of Dams in Southern Quebec (Canada)

The objective of this study is to use two hydrological indices (coefficients of variation and immoderation) to analyze the impacts of dam management methods on seasonal daily flow rate change downstream of three dams: Manouane (diversion-type management method), Ouareau (natural-type management method) and Matawin (inversion-type management method). The results show that this change is far greater downstream of the Matawin dam (characterized by an inversion-type management method) than downstream of the two other dams. Moreover, downstream of the Matawin dam, this daily flow rate change increases significantly over time, while decreasing downstream of the two other dams and in natural rivers. Lastly, this change is better correlated with climate downstream of the Ouareau dam than downstream of the two other dams. It is positively correlated with winter and spring temperatures as well as summer and fall rain. Contrary commonly accepted hypothesis, this study shows that the impacts of dams generally result in an increase of the seasonal flow rate change in Quebec.

Data security using random dynamic salting and AES based on master-slave keys for Iraqi dam management system

In the present time, dam management is considered one of the important challenges for e-government in Iraq, becuase it needs information technology infrastructure, data integrity and protection of user privacy against Internet threats that render such vital infrastructure ineffective. This struggle between the proposed dam management system (DMS) and a multi-tier secure model specifically for the Fallujah dam (and generally for all dams) which is addressed in this paper as a case study. To do this, a relational database design will discuss the development of a multi-tier secure model for integration of the dam management framework with its functions. This paper will discusse encryption and decryption of the dam data using the advanced encryption standard (AES) algorithm with derived keys via PBKDF2 and RNG sequences generator and Slave key for salting protection. The experimental results and analysis on the speed of encryption/decryption process, entropy value, plain text sensitivity, key sensitivity, keyspaceanalysis and histogram analysis will prove the the proposed scheme can impede the known attacks like brute force attacks, statistical and differential.Thus, the encryption scheme can be implemented on the proposed DMS and any other information system, as the implementation which will be presented in the results.

Beaver under spotlight in the Baltic Sea Region

The Eurasian beaver (Castor fiber L.) populations are considered to have reached densities causing substantial damage to forestry, e.g., in the south eastern Baltic Sea countries. The project Water Management in Baltic Forests WAMBAF of the Interreg Baltic Sea Region started in March 2016 and lasted for three years. WAMBAF committed to water management in Baltic forests and aimed to reduce nutrient and mercury export from forestry to streams, other water bodies towards the Baltic Sea. Three main topics like riparian forests, drainage system and beaver population / dam management that strongly related to mentioned issues. Protection of the Baltic Sea catchment is based on the protection of inland waters because the Sea gains the main inflow of nutrients and toxic compounds from inland watersThe Eurasian beaver (Castor fiber L.) populations are considered to have reached densities causing substantial damage to forestry, e.g., in the south eastern Baltic Sea countries. The project Water Management in Baltic Forests WAMBAF of the Interreg Baltic Sea Region started in March 2016 and lasted for three years. WAMBAF committed to water management in Baltic forests and aimed to reduce nutrient and mercury export from forestry to streams, other water bodies towards the Baltic Sea. Three main topics like riparian forests, drainage system and beaver population / dam management that strongly related to mentioned issues. Protection of the Baltic Sea catchment is based on the protection of inland waters because the Sea gains the main inflow of nutrients and toxic compounds from inland waters

Efficient dam management using SQL and GIS

This paper discusses use of SQL and GIS tools in nowadays dam management. Dam management requires the use of a highly-sophisticated measuring, monitoring and general management tools, since it is not only economical aspect of importance of these projects, but also about the security risks that require the highest possible caution and a precisely-developed control systems. Therefore, SQL and GIS are tools to be considered and implemented. GIS is widely used in spatial planning and connected management processes - because it allows easy way of storage, processing, analysis, modelling and display of spatial data. It has a wide range of features and is used in many areas. Structured Query Language (SQL) is a programming language for databases, written to be easy to understand and to use. SQL provides integration and presentation of data, optimization, easy reporting and analysis. In hand of trained professional analysts, SQL can make database search efficient and flexible, which is the key feature in demanding management processes as dam management).