Coastal Bluff Evolution in Response to a Rapid Rise in Surface Water Level

Abstract The spatial and temporal patterns of surface water (SW) - groundwater (GW) exchange are significantly affected by riverbed silting, clogging or erosion processes, by altering the thickness and hydraulic conductivity of riverbed sediments. The duration of SW-GW exchange is controlled by the drainage and infiltration resistance of river bottom sediments (e.g. Andrássy et al., 2012). Generally, these two parameters primarily depend on the hydraulic conductivity and on the thickness of clogged layer. In this study the flow processes between GW and SW were modeled by model TRIWACO for different infiltration resistance and drainage resistance of riverbed sediments. The model area is situated on the Rye Island, which is a lowland area with very low slope. In this area a channel network was built up, where the flow conditions are controlled by water-gates. Because of the low slope and the system of water gates built on the channels, the riverbeds are influenced by intensive clogging processes. First, the applicability of model TRIWACO in the study area was tested by modelling the response of GW on SW level fluctuation. It was simulated, how the regulation of water level and flow direction in the channels influence the GW level, especially in extreme hydrological conditions (drought/flood), and if the GW flow direction and GW level change as it was expected. Next, the influence of channel network silting up on GW-SW interaction was modeled. The thickness of riverbed sediments was measured and their hydraulic conductivity from disturbed sediment samples was evaluated. The assessed hydraulic conductivity was used to calculate the infiltration resistance and the drainage resistance of riverbed sediments in the study area. Then, the GW level and flow direction was simulated for different infiltration resistance and drainage resistance of sediments.

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Gypsum saturation degrees and precipitation potentials from Dead Sea - seawater mixtures

Environmental Chemistry ◽

10.1071/en09038 ◽

2009 ◽

Vol 6 (5) ◽

pp. 416 ◽

Cited By ~ 17

Author(s):

Itay J. Reznik ◽

Jiwchar Ganor ◽

Assaf Gal ◽

Ittai Gavrieli

Keyword(s):

Surface Water ◽

Water Level ◽

Water Column ◽

Sea Water ◽

Theoretical Calculations ◽

Dead Sea ◽

Gypsum Precipitation ◽

The Dead ◽

Rate Of Decline ◽

The 1960S

Environmental context. Since the 1960s the Dead Sea water level has dropped by nearly 30 m and over the last decade the rate of decline accelerated to over 1 m per year. Conveying seawater to the Dead Sea to stabilise or even raise its water level is currently being considered but may result in ‘whitening’ of the surface water through the formation of minute gypsum crystals that will remain suspended in the water column for a prolonged period of time. This paper is a first step in attaining the relevant physical and chemical parameters required to assess the potential for such whitening of the Dead Sea. Abstract. Introduction of seawater to the Dead Sea (DS) to stabilise its level raises paramount environmental questions. A major concern is that massive nucleation and growth of minute gypsum crystals will occur as a result of mixing between the SO42–-rich Red Sea (RS) water and Ca2+-rich DS brine. If the gypsum will not settle quickly to the bottom it may influence the general appearance of the DS by ‘whitening’ the surface water. Experimental observations and theoretical calculations of degrees of saturation with respect to gypsum (DSG) and gypsum precipitation potentials (PPT) were found to agree well, over the large range but overall high ionic strength of DS–RS mixtures. The dependency of both DSG and PPT on temperature was examined as well. Based on our thermodynamic insights, slow discharge of seawater to the DS will result in a relatively saline upper water column which will lead to enhanced gypsum precipitation.

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Application of Kriging to surface water level estimation

Canadian Journal of Civil Engineering ◽

10.1139/l92-018 ◽

1992 ◽

Vol 19 (1) ◽

pp. 181-185 ◽

Cited By ~ 1

Author(s):

Zolt Zrinji ◽

Donald H. Burn

Keyword(s):

Surface Water ◽

Water Level ◽

Spatial Interpolation ◽

Input Data ◽

Surface Profile ◽

Large Lake ◽

Additional Information ◽

Average Water ◽

Estimation System ◽

Water Elevation

The Kriging technique is used as the interpolation component of a surface water level estimation system applicable to the estimation of the water surface profile and the associated average water level for a large lake or reservoir. The estimation system is applied to the problem of determining the average surface water elevation of Lake Winnipeg, a large multipurpose lake located in central Manitoba, Canada. The Kriging system is demonstrated to produce daily average water level estimates that are not only comparable to the results from two existing techniques but are also available earlier, in a real-time context. Additional information obtained from the basic estimation system, which can assist in identifying inconsistent input data sources, are also discussed. Key words: lake level estimation, Kriging, spatial interpolation.

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Model Predictive Control of Salinity and Water Level in a Hypothetical Polder Ditch: Is it Possible to Use the Discretized Linearized Physical Equations for Optimization

10.29007/rpmp ◽

2018 ◽

Author(s):

Boran Ekin Aydin ◽

Martine Rutten ◽

Edo Abraham

Keyword(s):

Surface Water ◽

Model Predictive Control ◽

Water Level ◽

Fresh Water ◽

Predictive Control ◽

Internal Model ◽

Management Strategies ◽

Test Case ◽

Ongoing Research ◽

Saline Groundwater

Surface water salinization in deltaic areas due to saline groundwater exfiltration is an important issue. Fresh water diverted from the rivers is used for flushing the canals and the ditches in coastal areas to remove the low quality saline surface water mixed with saline groundwater. Worldwide, deltaic areas are under stress due to climate change, sea level increase and decrease in fresh water availability. The current fresh water management strategies in polders to overcome the salinization problem solely depends on uncontrolled freshwater use. However, this operation will not be effective during a scarce freshwater availability scenario and has to be revised for efficient management possibilities. With the advances in real time measurement of salinity and water level measurements, using a Model Predictive Control (MPC) scheme for the operation of a polder system is gaining popularity. MPC is a powerful control tool that can handle multiple objectives, consider the constraints and the uncertainties of the system. However, a MPC scheme requires a simple and reliable internal model that will be used to calculate the optimum control actions. The internal model should be robust, should reflect the system behaviour with enough detail and should not be computationally costly. In this paper, a MPC scheme is proposed using the discretized linearized De Saint Venant (SV) and Advection-Diffusion (AD) equations as the internal model of the controller. The proposed scheme will be able to control salinity and water level at any discretization point by manipulating the flushing and outflow discharges. This is an ongoing research with tests continuing on a realistic test case.

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COUPLED GROUNDWATER-SURFACE WATER LEVEL MODELLING ON A CONTINENTAL TO GLOBAL SCALE

10.1130/abs/2020nc-347638 ◽

2020 ◽

Author(s):

Kerry L. Callaghan ◽

◽

Andrew D. Wickert ◽

Richard Barnes

Keyword(s):

Surface Water ◽

Water Level ◽

Global Scale

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