From pristine to present state: hydrology evolution of Lake Saint-François, St. Lawrence River

Jean Morin; Michel Leclerc

doi:10.1139/l98-019

From pristine to present state: hydrology evolution of Lake Saint-François, St. Lawrence River

Canadian Journal of Civil Engineering ◽

10.1139/l98-019 ◽

1998 ◽

Vol 25 (5) ◽

pp. 864-879 ◽

Cited By ~ 15

Author(s):

Jean Morin ◽

Michel Leclerc

Keyword(s):

Water Level ◽

Plant Biomass ◽

Seasonal Pattern ◽

Water Levels ◽

Ship Traffic ◽

Water Level Rise ◽

Hydropower Production ◽

Discharge Regulation ◽

The Impact ◽

St Lawrence River

Lake Saint-François is a relatively shallow fluvial lake of the St. Lawrence River with numerous deep channels. This complex system has been considerably altered from its pristine state 150 years ago. Currently, the water level is stabilized and the flow is regulated; important areas have been dredged and the major part of its outflow is diverted through the Beauharnois canal. The evolution of water levels shows a trend towards stabilization as required for ship traffic in the St. Lawrence Seaway and for hydropower production. With the construction of the Moses-Saunders dam in 1960, the flow of the river could be regulated; changes occur in the seasonal pattern of the flow. Ancient stage-discharge relationships were recreated to describe the impact of the 1849 damming and of the present level stabilization. Stabilization of the water level has favored the growth of submerged plants. Manning's friction coefficient was used to show that plant biomass has doubled since 1920; the onset of biomass increases corresponds to a water level stabilization event. The distribution of wetlands in the Lake Saint-François area was drastically modified by the water level rise caused by the 1849 damming. New wetlands were created and pre-1849 wetlands, located on what are currently shoals in the central part of the lake, have totally disappeared.Key words: Lake Saint-François, St. Lawrence River, impact of civil works, flow discharge regulation, water level regulation, wetland flooding cycle, submerged macrophyte, ecosystem reaction, civil work history.

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Impact of water level fluctuations on St. Lawrence River aquatic vegetation

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-201 ◽

1997 ◽

Vol 54 (12) ◽

pp. 2853-2865 ◽

Cited By ~ 78

Author(s):

Christiane Hudon

Keyword(s):

Water Level ◽

Aquatic Vegetation ◽

Plant Biomass ◽

Plant Cover ◽

Negative Relationship ◽

Climatic Conditions ◽

Water Levels ◽

Water Level Fluctuations ◽

Vertical Range ◽

St Lawrence River

Historical records of average seasonal water levels in the St. Lawrence River over the past 80 years reveal cyclic variations of up to 1 m above (1976) and 1 m below (1965) present levels. These variations are probably related to climatic conditions in the basin. Over the same period, the vertical range of seasonal water levels decreased from 2.2 to 1.5 m because of discharge regulation. Exposure of new substrate during periods of extreme low water levels may facilitate the invasion of aggressive and (or) exotic species. In Lake Saint-Pierre, a strong negative relationship was observed between seasonal water level and the percentage of emergent plant cover. Under low water levels, the lake becomes a large (387 km2) marshland that could support a high plant biomass (286 times 103 t) whereas under high water levels, the lake shifts to a vast (501 km2) open-water body with a lower predicted plant biomass (117 times 103 t). A model of the major anthropic and climatic forces acting on water levels is also presented; it describes aquatic plant biomass allocation and species diversity under different water level conditions.

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Determining Extreme Still Water Levels for Design and Planning Purposes Incorporating Sea Level Rise: Sydney, Australia

Atmosphere ◽

10.3390/atmos13010095 ◽

2022 ◽

Vol 13 (1) ◽

pp. 95

Author(s):

Phil J. Watson

Keyword(s):

Sea Level Rise ◽

Water Level ◽

Sea Level ◽

Tide Gauge ◽

Water Levels ◽

Extreme Value Analysis ◽

Tide Gauge Record ◽

Value Analysis ◽

Mean Sea Level ◽

The Impact

This paper provides an Extreme Value Analysis (EVA) of the hourly water level record at Fort Denison dating back to 1915 to understand the statistical likelihood of the combination of high predicted tides and the more dynamic influences that can drive ocean water levels higher at the coast. The analysis is based on the Peaks-Over-Threshold (POT) method using a fitted Generalised Pareto Distribution (GPD) function to estimate extreme hourly heights above mean sea level. The analysis highlights the impact of the 1974 East Coast Low event and rarity of the associated measured water level above mean sea level at Sydney, with an estimated return period exceeding 1000 years. Extreme hourly predictions are integrated with future projections of sea level rise to provide estimates of relevant still water levels at 2050, 2070 and 2100 for a range of return periods (1 to 1000 years) for use in coastal zone management, design, and sea level rise adaptation planning along the NSW coastline. The analytical procedures described provide a step-by-step guide for practitioners on how to develop similar baseline information from any long tide gauge record and the associated limitations and key sensitivities that must be understood and appreciated in applying EVA.

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The Role of Mean Sea Level Annual Cycle on Extreme Water Levels Along European Coastline

Remote Sensing ◽

10.3390/rs12203419 ◽

2020 ◽

Vol 12 (20) ◽

pp. 3419

Author(s):

Tomás Fernández-Montblanc ◽

Jesús Gómez-Enri ◽

Paolo Ciavola

Keyword(s):

Water Level ◽

Sea Level ◽

North Sea ◽

Extreme Events ◽

Annual Cycle ◽

Coastal Flooding ◽

Water Levels ◽

Total Water ◽

Mean Sea Level ◽

The Impact

The knowledge of extreme total water levels (ETWLs) and the derived impact, coastal flooding and erosion, is crucial to face the present and future challenges exacerbated in European densely populated coastal areas. Based on 24 years (1993–2016) of multimission radar altimetry, this paper investigates the contribution of each water level component: tide, surge and annual cycle of monthly mean sea level (MMSL) to the ETWLs. It focuses on the contribution of the annual variation of MMSL in the coastal flooding extreme events registered in a European database. In microtidal areas (Black, Baltic and Mediterranean Sea), the MMSL contribution is mostly larger than tide, and it can be at the same order of magnitude of the surge. In meso and macrotidal areas, the MMSL contribution is <20% of the total water level, but larger (>30%) in the North Sea. No correlation was observed between the average annual cycle of monthly mean sea level (AMMSL) and coastal flooding extreme events (CFEEs) along the European coastal line. Positive correlations of the component variance of MMSL with the relative frequency of CFEEs extend to the Central Mediterranean (r = 0.59), North Sea (r = 0.60) and Baltic Sea (r = 0.75). In the case of positive MMSL anomalies, the correlation expands to the Bay of Biscay and northern North Atlantic (at >90% of statistical significance). The understanding of the spatial and temporal patterns of a combination of all the components of the ETWLs shall improve the preparedness and coastal adaptation measures to reduce the impact of coastal flooding.

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Explicit Finite Element Study of Liquid Sloshing Behavior in Fluid-Structure Interaction Condition

Volume 7: Fluids Engineering ◽

10.1115/imece2017-70832 ◽

2017 ◽

Author(s):

Shuo Yang ◽

Raymond K. Yee

Keyword(s):

Finite Element ◽

Water Level ◽

Similarity Theory ◽

Fluid Structure Interaction ◽

Water Levels ◽

Tank Wall ◽

Fluid Structure ◽

Structure Interaction ◽

Sloshing Phenomenon ◽

The Impact

As a common phenomenon in liquid motions, sloshing usually happens in a partially filled liquid tank of moving vehicle or structure. The objectives of this paper are to study sloshing behavior in rigid tank and deformable tank, and to develop a better performance baffle design in the tank under seismic excitations. The tank is surged with a sinusoidal oscillation about horizontal x-direction. The hydro-elasticity effect of sloshing pressure on the tank wall was taken into consideration due to the fluid-structure interaction between impact pressures and tank structures. ABAQUS finite element program using Coupled Eulerian-Lagrangian (CEL) technique was employed to simulate fluid sloshing. The sloshing phenomenon was studied in rigid tank and deformable tank models with three different water levels, and the effect of wall thickness of the deformable tank on sloshing behavior was discussed. One way to minimize the effect of sloshing in a tank, baffles are used and installed in the middle of the tank, and then various heights and material types of baffle were evaluated. The simulation results show that higher water level case creates greater pressure impact on the tank wall than lower water level case, and the elasticity of the tank structure would reduce the impact pressure of the wall. For the simulation tank model with size of 1m (H) × 1m (W) × 0.2m (D), better performance baffle was found to be the one with the height of 0.35m and was made of acrylic material. Moreover, the conclusion of this study can be extrapolated to other dimensions of the model based on similarity theory. This paper also can serve as an aid in further studying sloshing phenomenon. The findings of this study can be applied to restrain or minimize sloshing motions inside a tank.

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Monitoring Temporal Change of River Islands in the Yangtze River by Remotely Sensed Data

Water ◽

10.3390/w10101484 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1484 ◽

Cited By ~ 1

Author(s):

Jinyan Sun ◽

Lei Ding ◽

Jiaze Li ◽

Haiming Qian ◽

Mengting Huang ◽

...

Keyword(s):

Water Level ◽

Yangtze River ◽

Temporal Change ◽

Flood Disaster ◽

Water Levels ◽

Sediment Supply ◽

The Yangtze River ◽

Flood Warning ◽

River Islands ◽

The Impact

The spatial extent and area of river islands are always changing due to the impact of hydrodynamic conditions, sediment supply and human activities. A catastrophic flood disaster was driven by sustained and heavy rainfall around the middle and lower Yangtze River in 18 June to 21 July 2016. The flood resulted in the most serious social-economic loss since 1954 and caused a larger-scale inundation for a short time. It is essential to continuously monitor the dynamics changes of river islands because this can avoid frequent field measurements in river islands before and after flood disasters, which are helpful for flood warning. This paper focuses on the temporal change of three river islands called Fenghuangzhou, Changshazhou, and one uninhabited island in the Yangtze River in 2016. In this study, GF-1 (GaoFen-1) WFV (wide field view) data was used for our study owing to its fine spatial and temporal resolution. A simple NDWI (Normalized Difference Water Index) method was used for the river island mapping. Human checking was then performed to ensure mapping accuracy. We estimated the relationship between the area of river islands and measured water levels using four models. Furthermore, we mapped the spatial pattern of inundation risk of river islands. The results indicate a good ability of the GF-1 WFV data with a 16-m spatial resolution to characterize the variation of river islands and to study the association between flood disaster and river islands. A significantly negative but nonlinear relationship between the water level and the area of the river island was observed. We also found that the cubic function fits best among three models (R2 > 0.8, P < 0.001). The maximum of the inundated area at the river island appeared in the rainy season on 8 July 2016 and the minimum occurred in the dry season on 28 December 2016, which is consistent with the water level measured by the hydrological station. Our results derived from GF-1 data can provide a useful reference for decision-making of flood warning, disaster assessment, and post-disaster reconstruction.

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Tree-ring analysis of wetlands of the upper St. Lawrence River, Quebec: response to hydrology and climate

Canadian Journal of Forest Research ◽

10.1139/x26-054 ◽

1996 ◽

Vol 26 (3) ◽

pp. 482-491 ◽

Cited By ~ 12

Author(s):

Martin Jean ◽

André Bouchard

Keyword(s):

Water Level ◽

Tree Growth ◽

Significant Relationship ◽

Water Levels ◽

Water Level Fluctuations ◽

Climatic Fluctuations ◽

Climatic Variations ◽

Temperature And Precipitation ◽

Growth Variation ◽

St Lawrence River

A dendrochronological analysis of three tree species colonizing a swamp along the St. Lawrence River was undertaken to (a) study the extent to which water-level fluctuations have an impact on tree growth in comparison to climatic variations; (b) compare the responses of three species (Acerrubrum L., Larixlaricina (Du Roi) K. Koch, and Thujaoccidentalis L.) with hydrologic and climatic variations; and (c) examine the duration of the influence of water-level fluctuations on tree growth. Tree cores from 78 stands were cross-dated and verified with COFECHA and a master chronology for each species was produced using ARSTAN. Response function analyses were used to measure the influence of climate (temperature and precipitation) and water level on tree growth. Water-level fluctuations have a significant influence on A. rubrum growth, accounting for 30% of the tree growth variation. A significant relationship exists between L. laricina and water-level fluctuations, but only 9% of the tree growth is explained by hydrology. No significant relationship was found between water levels and T. occidentalis growth. Climatic fluctuations are a more important influence on growth for all three species, accounting for 46% to 51% of the tree growth variation not explained by water levels.

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An Investigation Concerning the Impact of Climate Changes on the Water Equilibrium in the Egyptian Nile Delta

Annals of Valahia University of Targoviste Geographical Series ◽

10.1515/avutgs-2017-0006 ◽

2017 ◽

Vol 17 (1) ◽

pp. 58-69

Author(s):

Mohamed A. Ashour ◽

Tawab E. Aly ◽

Yousra A. Eldegwee

Keyword(s):

Ground Water ◽

Water Level ◽

Climate Changes ◽

Sea Water ◽

Nile Delta ◽

Salt Water ◽

Water Level Rise ◽

Productive Land ◽

Water Equilibrium ◽

The Impact

AbstractIn such problematic water situation in Egypt, control and saving of the available limited quantity takes great importance from both technical and national points of view. In addition to all the well-known traditional reasons of the problem such as pollution, over usage, and bad traditions of dealing with water, a new very important reason is added nowadays, called “Climate Changes” which has a direct impact on sea water rising, that causes a serious attack of the salt water to the fresh water especially in River Deltas., Not only the surface water, but also the ground water. Since that process proved some acceleration, several investigations have recently considered the worst impacts of climate change and sea water level rise on sea water intrusion. Most of them have revealed the severity of such problem, and the significance of the land movement of the dispersion zone under the sea water level rise situation. In this paper, we try to introduce a technical review and study for the most popular studies concerning our topic, and its most important conclusions, as an approach for preparing the Ph.D. thesis about the Nile Delta water equilibrium in the light of the expected Mediterranean Sea water level rise. Nile Delta, which located between Damietta Branch on the East, and Rosetta Branch on the west, occupies about 20000 square kilometers of the most rich, productive land in Egypt. About 50% of Egyptian population live in that area, agriculture is the main human activities on them, so water is the prime factor in their life, and their agriculture investments. The great amount of this investment depends on the ground water, which faces a serious challenge due to, two reasons, first, is the overuse, and over pumping, while the second is the attack of the salt water due to the Mediterranean Seawater level rise, because of the climate changes. These two reasons must be overcome, if the first reason can be controlled by law, and technical roles, the second reason needs intensive studies and investigations concerning the interaction between seawater and fresh ground water.

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Shift in wetland plant composition and biomass following low-level episodes in the St. Lawrence River: looking into the future

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f04-031 ◽

2004 ◽

Vol 61 (4) ◽

pp. 603-617 ◽

Cited By ~ 40

Author(s):

Christiane Hudon

Keyword(s):

Plant Biomass ◽

Lythrum Salicaria ◽

Water Levels ◽

Water Level Fluctuations ◽

Terrestrial Plants ◽

Hydrologic Variability ◽

Najas Flexilis ◽

Average Water ◽

Similar Episode ◽

St Lawrence River

The effects of a 1-m drop in average water levels in 1999 on species composition and biomass were documented for a St. Lawrence River wetland and compared with a similar episode in 1931. These observations highlight the manifold effects of past and future water level fluctuations on St. Lawrence River wetlands and faunal habitats, resulting from natural hydrologic variability, climate change, and (or) human intervention. In 1931 and 1999, waters were 23 °C warmer than the previous 10-year average. Low water levels markedly altered wetland vegetation: various Graminea (including Phalaris arundinacea and Phragmites australis) and facultative annual species invaded previously marshy areas. Submerged species previously found in shallow waters were replaced on dry ground by annual terrestrial plants; Alisma gramineum colonized emergent waterlogged mudflats. The low water levels of 1999 induced a spatially discontinuous plant biomass that was richer in terrestrial material than in previous years (19931994). In comparison with the 1930s, recent surveys indicate a decline of assemblages dominated by Equisetum spp. and Najas flexilis and a rise of those dominated by Lythrum salicaria, Potamogeton spp., and filamentous algae. These shifts reveal the additional effects of nutrient enrichment, alien species, and shoreline alteration accompanying a change from a mostly agricultural to a mostly urbanized and industrialized landscape.

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Hydrometeorological drivers of flood characteristics in the Brahmaputra river basin in Bangladesh

10.5194/hess-2021-97 ◽

2021 ◽

Author(s):

Sazzad Hossain ◽

Hannah L. Cloke ◽

Andrea Ficchì ◽

Andrew G. Turner ◽

Elisabeth M. Stephens

Keyword(s):

Water Level ◽

Morphological Changes ◽

High Water ◽

Water Levels ◽

Future Climate Change ◽

South Asian Summer Monsoon ◽

Large Variability ◽

Long Duration ◽

The Impact ◽

Flood Characteristics

Abstract. While flooding is an annual occurrence in the Brahmaputra basin during the South Asian summer monsoon, there is large variability in the flood characteristics that drive risk: flood duration, rate of water level rise and peak water level. The aim of this study is to understand the key hydrometeorological drivers influencing these flood characteristics. We analyse hydrometeorological time series of the last 33 years to understand flood dynamics focusing on three extraordinary floods in 1998 (long duration), 2017 (rapid rise) and 2019 (high water level). We find that long duration floods in the basin have been driven by basin-wide seasonal rainfall extremes associated with the development phase of strong La Niña events, whereas floods with a rapid rate of rise have been driven by more localized rainfall falling in a hydrological ‘sweet spot’ that leads to a concurrent contribution from the tributaries into the main stem of the river. We find that recent record high water levels are not coincident with extreme river flows, hinting that sedimentation and morphological changes are also important drivers of flood risk that should be further investigated. Understanding these drivers is essential for flood forecasting and early warning and also to study the impact of future climate change on flood.

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