Author: Jonathan A. Czuba
Publisher: U.S. Department of the Interior, U.S. Geological Survey
ISBN:
Category :
Languages : en
Pages : 150
Book Description
A study of the geomorphology of rivers draining Mount Rainier, Washington, was completed to identify sources of sediment to the river network; to identify important processes in the sediment delivery system; to assess current sediment loads in rivers draining Mount Rainier; to evaluate if there were trends in streamflow or sediment load since the early 20th century; and to assess how rates of sedimentation might continue into the future using published climate-change scenarios. Rivers draining Mount Rainier carry heavy sediment loads sourced primarily from the volcano that cause acute aggradation in deposition reaches as far away as the Puget Lowland. Calculated yields ranged from 2,000 tonnes per square kilometer per year [(tonnes/km2)/yr] on the upper Nisqually River to 350 (tonnes/km2)/yr on the lower Puyallup River, notably larger than sediment yields of 50–200 (tonnes/km2)/yr typical for other Cascade Range rivers. These rivers can be assumed to be in a general state of sediment surplus. As a result, future aggradation rates will be largely influenced by the underlying hydrology carrying sediment downstream. The active-channel width of rivers directly draining Mount Rainier in 2009, used as a proxy for sediment released from Mount Rainier, changed little between 1965 and 1994 reflecting a climatic period that was relatively quiet hydrogeomorphically. From 1994 to 2009, a marked increase in geomorphic disturbance caused the active channels in many river reaches to widen. Comparing active-channel widths of glacier-draining rivers in 2009 to the distance of glacier retreat between 1913 and 1994 showed no correlation, suggesting that geomorphic disturbance in river reaches directly downstream of glaciers is not strongly governed by the degree of glacial retreat. In contrast, there was a correlation between active-channel width and the percentage of superglacier debris mantling the glacier, as measured in 1971. A conceptual model of sediment delivery processes from the mountain indicates that rockfalls, glaciers, debris flows, and main-stem flooding act sequentially to deliver sediment from Mount Rainier to river reaches in the Puget Lowland over decadal time scales. Greater-than-normal runoff was associated with cool phases of the Pacific Decadal Oscillation. Streamflow-gaging station data from four unregulated rivers directly draining Mount Rainier indicated no statistically significant trends of increasing peak flows over the course of the 20th century. The total sediment load of the upper Nisqually River from 1945 to 2011 was determined to be 1,200,000±180,000 tonnes/yr. The suspended-sediment load in the lower Puyallup River at Puyallup, Washington, was 860,000±300,000 tonnes/yr between 1978 and 1994, but the long-term load for the Puyallup River likely is about 1,000,000±400,000 tonnes/yr. Using a coarse-resolution bedload transport relation, the long-term average bedload was estimated to be about 30,000 tonnes/yr in the lower White River near Auburn, Washington, which was four times greater than bedload in the Puyallup River and an order of magnitude greater than bedload in the Carbon River. Analyses indicate a general increase in the sediment loads in Mount Rainier rivers in the 1990s and 2000s relative to the time period from the 1960s to 1980s. Data are insufficient, however, to determine definitively if post-1990 increases in sediment production and transport from Mount Rainier represent a statistically significant increase relative to sediment-load values typical from Mount Rainier during the entire 20th century. One-dimensional river-hydraulic and sediment-transport models simulated the entrainment, transport, attrition, and deposition of bed material. Simulations showed that bed-material loads were largest for the Nisqually River and smallest for the Carbon River. The models were used to simulate how increases in sediment supply to rivers transport through the river systems and affect lowland reaches. For each simulation, the input sediment pulse evolved through a combination of translation, dispersion, and attrition as it moved downstream. The characteristic transport times for the median sediment-size pulse to arrive downstream for the Nisqually, Carbon, Puyallup, and White Rivers were approximately 70, 300, 80, and 60 years, respectively.
Geomorphic analysis of the river response to sedimentation downstream of Mount Rainier, Washington
Author: Jonathan A. Czuba
Publisher: U.S. Department of the Interior, U.S. Geological Survey
ISBN:
Category :
Languages : en
Pages : 150
Book Description
A study of the geomorphology of rivers draining Mount Rainier, Washington, was completed to identify sources of sediment to the river network; to identify important processes in the sediment delivery system; to assess current sediment loads in rivers draining Mount Rainier; to evaluate if there were trends in streamflow or sediment load since the early 20th century; and to assess how rates of sedimentation might continue into the future using published climate-change scenarios. Rivers draining Mount Rainier carry heavy sediment loads sourced primarily from the volcano that cause acute aggradation in deposition reaches as far away as the Puget Lowland. Calculated yields ranged from 2,000 tonnes per square kilometer per year [(tonnes/km2)/yr] on the upper Nisqually River to 350 (tonnes/km2)/yr on the lower Puyallup River, notably larger than sediment yields of 50–200 (tonnes/km2)/yr typical for other Cascade Range rivers. These rivers can be assumed to be in a general state of sediment surplus. As a result, future aggradation rates will be largely influenced by the underlying hydrology carrying sediment downstream. The active-channel width of rivers directly draining Mount Rainier in 2009, used as a proxy for sediment released from Mount Rainier, changed little between 1965 and 1994 reflecting a climatic period that was relatively quiet hydrogeomorphically. From 1994 to 2009, a marked increase in geomorphic disturbance caused the active channels in many river reaches to widen. Comparing active-channel widths of glacier-draining rivers in 2009 to the distance of glacier retreat between 1913 and 1994 showed no correlation, suggesting that geomorphic disturbance in river reaches directly downstream of glaciers is not strongly governed by the degree of glacial retreat. In contrast, there was a correlation between active-channel width and the percentage of superglacier debris mantling the glacier, as measured in 1971. A conceptual model of sediment delivery processes from the mountain indicates that rockfalls, glaciers, debris flows, and main-stem flooding act sequentially to deliver sediment from Mount Rainier to river reaches in the Puget Lowland over decadal time scales. Greater-than-normal runoff was associated with cool phases of the Pacific Decadal Oscillation. Streamflow-gaging station data from four unregulated rivers directly draining Mount Rainier indicated no statistically significant trends of increasing peak flows over the course of the 20th century. The total sediment load of the upper Nisqually River from 1945 to 2011 was determined to be 1,200,000±180,000 tonnes/yr. The suspended-sediment load in the lower Puyallup River at Puyallup, Washington, was 860,000±300,000 tonnes/yr between 1978 and 1994, but the long-term load for the Puyallup River likely is about 1,000,000±400,000 tonnes/yr. Using a coarse-resolution bedload transport relation, the long-term average bedload was estimated to be about 30,000 tonnes/yr in the lower White River near Auburn, Washington, which was four times greater than bedload in the Puyallup River and an order of magnitude greater than bedload in the Carbon River. Analyses indicate a general increase in the sediment loads in Mount Rainier rivers in the 1990s and 2000s relative to the time period from the 1960s to 1980s. Data are insufficient, however, to determine definitively if post-1990 increases in sediment production and transport from Mount Rainier represent a statistically significant increase relative to sediment-load values typical from Mount Rainier during the entire 20th century. One-dimensional river-hydraulic and sediment-transport models simulated the entrainment, transport, attrition, and deposition of bed material. Simulations showed that bed-material loads were largest for the Nisqually River and smallest for the Carbon River. The models were used to simulate how increases in sediment supply to rivers transport through the river systems and affect lowland reaches. For each simulation, the input sediment pulse evolved through a combination of translation, dispersion, and attrition as it moved downstream. The characteristic transport times for the median sediment-size pulse to arrive downstream for the Nisqually, Carbon, Puyallup, and White Rivers were approximately 70, 300, 80, and 60 years, respectively.
Publisher: U.S. Department of the Interior, U.S. Geological Survey
ISBN:
Category :
Languages : en
Pages : 150
Book Description
A study of the geomorphology of rivers draining Mount Rainier, Washington, was completed to identify sources of sediment to the river network; to identify important processes in the sediment delivery system; to assess current sediment loads in rivers draining Mount Rainier; to evaluate if there were trends in streamflow or sediment load since the early 20th century; and to assess how rates of sedimentation might continue into the future using published climate-change scenarios. Rivers draining Mount Rainier carry heavy sediment loads sourced primarily from the volcano that cause acute aggradation in deposition reaches as far away as the Puget Lowland. Calculated yields ranged from 2,000 tonnes per square kilometer per year [(tonnes/km2)/yr] on the upper Nisqually River to 350 (tonnes/km2)/yr on the lower Puyallup River, notably larger than sediment yields of 50–200 (tonnes/km2)/yr typical for other Cascade Range rivers. These rivers can be assumed to be in a general state of sediment surplus. As a result, future aggradation rates will be largely influenced by the underlying hydrology carrying sediment downstream. The active-channel width of rivers directly draining Mount Rainier in 2009, used as a proxy for sediment released from Mount Rainier, changed little between 1965 and 1994 reflecting a climatic period that was relatively quiet hydrogeomorphically. From 1994 to 2009, a marked increase in geomorphic disturbance caused the active channels in many river reaches to widen. Comparing active-channel widths of glacier-draining rivers in 2009 to the distance of glacier retreat between 1913 and 1994 showed no correlation, suggesting that geomorphic disturbance in river reaches directly downstream of glaciers is not strongly governed by the degree of glacial retreat. In contrast, there was a correlation between active-channel width and the percentage of superglacier debris mantling the glacier, as measured in 1971. A conceptual model of sediment delivery processes from the mountain indicates that rockfalls, glaciers, debris flows, and main-stem flooding act sequentially to deliver sediment from Mount Rainier to river reaches in the Puget Lowland over decadal time scales. Greater-than-normal runoff was associated with cool phases of the Pacific Decadal Oscillation. Streamflow-gaging station data from four unregulated rivers directly draining Mount Rainier indicated no statistically significant trends of increasing peak flows over the course of the 20th century. The total sediment load of the upper Nisqually River from 1945 to 2011 was determined to be 1,200,000±180,000 tonnes/yr. The suspended-sediment load in the lower Puyallup River at Puyallup, Washington, was 860,000±300,000 tonnes/yr between 1978 and 1994, but the long-term load for the Puyallup River likely is about 1,000,000±400,000 tonnes/yr. Using a coarse-resolution bedload transport relation, the long-term average bedload was estimated to be about 30,000 tonnes/yr in the lower White River near Auburn, Washington, which was four times greater than bedload in the Puyallup River and an order of magnitude greater than bedload in the Carbon River. Analyses indicate a general increase in the sediment loads in Mount Rainier rivers in the 1990s and 2000s relative to the time period from the 1960s to 1980s. Data are insufficient, however, to determine definitively if post-1990 increases in sediment production and transport from Mount Rainier represent a statistically significant increase relative to sediment-load values typical from Mount Rainier during the entire 20th century. One-dimensional river-hydraulic and sediment-transport models simulated the entrainment, transport, attrition, and deposition of bed material. Simulations showed that bed-material loads were largest for the Nisqually River and smallest for the Carbon River. The models were used to simulate how increases in sediment supply to rivers transport through the river systems and affect lowland reaches. For each simulation, the input sediment pulse evolved through a combination of translation, dispersion, and attrition as it moved downstream. The characteristic transport times for the median sediment-size pulse to arrive downstream for the Nisqually, Carbon, Puyallup, and White Rivers were approximately 70, 300, 80, and 60 years, respectively.
Tahoma and Its People
Author: Jeff Antonelis-Lapp
Publisher: Washington State University Press
ISBN: 1636820654
Category : Nature
Languages : en
Pages : 365
Book Description
A magnificent active volcano, Mount Rainier ascends to 14,410 feet above sea level--the highest in Washington State. The source of five major rivers, it has more glaciers than any other peak in the contiguous U.S. Its slopes are home to ancient forests, spectacular subalpine meadows, and unique, captivating creatures. In Tahoma and Its People, a passionate, informed, hands-on science educator presents a natural and environmental history of Mount Rainier National Park and the surrounding region. Jeff Antonelis-Lapp explores geologic processes that create and alter landscapes, interrelationships within and between plant and animal communities, weather and climate influences on ecosystems, and what linked the iconic mountain with the people who traveled to it for millennia. He intersperses his own direct observation and study of organisms, as well as personal interactions with rangers, archaeologists, a master Native American weaver, and others. He covers a plethora of topics: geology, archaeology, indigenous villages and use of resources, climate and glacier studies, alpine and forest ecology, rivers, watershed dynamics, keystone species, threatened wildlife, geological hazards, and current resource management. Numerous color illustrations, maps, and figures supplement the text. 2020 Banff Mountain Book Competition Finalist, Mountain Environment and Natural History category
Publisher: Washington State University Press
ISBN: 1636820654
Category : Nature
Languages : en
Pages : 365
Book Description
A magnificent active volcano, Mount Rainier ascends to 14,410 feet above sea level--the highest in Washington State. The source of five major rivers, it has more glaciers than any other peak in the contiguous U.S. Its slopes are home to ancient forests, spectacular subalpine meadows, and unique, captivating creatures. In Tahoma and Its People, a passionate, informed, hands-on science educator presents a natural and environmental history of Mount Rainier National Park and the surrounding region. Jeff Antonelis-Lapp explores geologic processes that create and alter landscapes, interrelationships within and between plant and animal communities, weather and climate influences on ecosystems, and what linked the iconic mountain with the people who traveled to it for millennia. He intersperses his own direct observation and study of organisms, as well as personal interactions with rangers, archaeologists, a master Native American weaver, and others. He covers a plethora of topics: geology, archaeology, indigenous villages and use of resources, climate and glacier studies, alpine and forest ecology, rivers, watershed dynamics, keystone species, threatened wildlife, geological hazards, and current resource management. Numerous color illustrations, maps, and figures supplement the text. 2020 Banff Mountain Book Competition Finalist, Mountain Environment and Natural History category
River Flow 2020
Author: Wim Uijttewaal
Publisher: CRC Press
ISBN: 1000294366
Category : Technology & Engineering
Languages : en
Pages : 2459
Book Description
Rivers form one of the lifelines in our society by providing essential services such as availability of fresh water, navigation, energy, ecosystem services, and flood conveyance. Because of this essential role, mankind has interfered continuously in order to benefit most and at the same time avoid adverse consequences such as flood risk and droughts. This has resulted in often highly engineered rivers with a narrow set of functions. In the last decades rivers are increasingly considered in a more holistic manner as a system with a multitude of interdependent processes. River research and engineering has therefore added to the river fundamentals also themes like ecohydraulics, consequences of climate change, and urbanisation. River Flow 2020 contains the contributions presented at the 10th conference on Fluvial Hydraulics, River Flow 2020, organised under the auspices of the Committee on Fluvial Hydraulics of the International Association for Hydro-Environment Engineering and Research (IAHR). What should have been a lively physical gathering of researchers, students and practitioners, was converted into an online event as the COVID-19 pandemic hindered international travelling and large gatherings of people. Nevertheless, the fluvial hydraulics community showed their interest and to be very much alive with a high number of participations for such event. Since its first edition in 2002, in Louvain-la-Neuve, this series of conferences has found a large and loyal audience in the river research and engineering community while being also attractive to the new researchers and young professionals. This is highlighted by the large number of contributions applying for the Coleman award for young researchers, and also by the number of applications and attendants to the Master Classes which are aimed at young researchers and students. River Flow 2020 aims to provide an updated overview of the ongoing research in this wide range of topics, and contains five major themes which are focus of research in the fluvial environment: river fundamentals, the digital river, the healthy river, extreme events and rivers under pressure. Other highlights of River Flow 2020 include the substantial number of interdisciplinary subthemes and sessions of special interest. The contributions will therefore be of interest to academics in hydraulics, hydrology and environmental engineering as well as practitioners that would like to be updated about the newest findings and hot themes in river research and engineering.
Publisher: CRC Press
ISBN: 1000294366
Category : Technology & Engineering
Languages : en
Pages : 2459
Book Description
Rivers form one of the lifelines in our society by providing essential services such as availability of fresh water, navigation, energy, ecosystem services, and flood conveyance. Because of this essential role, mankind has interfered continuously in order to benefit most and at the same time avoid adverse consequences such as flood risk and droughts. This has resulted in often highly engineered rivers with a narrow set of functions. In the last decades rivers are increasingly considered in a more holistic manner as a system with a multitude of interdependent processes. River research and engineering has therefore added to the river fundamentals also themes like ecohydraulics, consequences of climate change, and urbanisation. River Flow 2020 contains the contributions presented at the 10th conference on Fluvial Hydraulics, River Flow 2020, organised under the auspices of the Committee on Fluvial Hydraulics of the International Association for Hydro-Environment Engineering and Research (IAHR). What should have been a lively physical gathering of researchers, students and practitioners, was converted into an online event as the COVID-19 pandemic hindered international travelling and large gatherings of people. Nevertheless, the fluvial hydraulics community showed their interest and to be very much alive with a high number of participations for such event. Since its first edition in 2002, in Louvain-la-Neuve, this series of conferences has found a large and loyal audience in the river research and engineering community while being also attractive to the new researchers and young professionals. This is highlighted by the large number of contributions applying for the Coleman award for young researchers, and also by the number of applications and attendants to the Master Classes which are aimed at young researchers and students. River Flow 2020 aims to provide an updated overview of the ongoing research in this wide range of topics, and contains five major themes which are focus of research in the fluvial environment: river fundamentals, the digital river, the healthy river, extreme events and rivers under pressure. Other highlights of River Flow 2020 include the substantial number of interdisciplinary subthemes and sessions of special interest. The contributions will therefore be of interest to academics in hydraulics, hydrology and environmental engineering as well as practitioners that would like to be updated about the newest findings and hot themes in river research and engineering.
Twenty-Sixth International Congress on Large Dams / Vingt-Sixième Congrès International des Grands Barrages
Author: CIGB ICOLD
Publisher: CRC Press
ISBN: 0429877560
Category : Technology & Engineering
Languages : en
Pages : 4633
Book Description
The International Committee on Large Dams (ICOLD) held its 26th International Congress in Vienna, Austria (1-7 July 2018). The proceedings of the congress focus on four main questions: 1. Reservoir sedimentation and sustainable development; 2. Safety and risk analysis; 3. Geology and dams, and 4. Small dams and levees. The book thoroughly discusses these questions and is indispensable for academics, engineers and professionals involved or interested in engineering, hydraulic engineering and related disciplines.
Publisher: CRC Press
ISBN: 0429877560
Category : Technology & Engineering
Languages : en
Pages : 4633
Book Description
The International Committee on Large Dams (ICOLD) held its 26th International Congress in Vienna, Austria (1-7 July 2018). The proceedings of the congress focus on four main questions: 1. Reservoir sedimentation and sustainable development; 2. Safety and risk analysis; 3. Geology and dams, and 4. Small dams and levees. The book thoroughly discusses these questions and is indispensable for academics, engineers and professionals involved or interested in engineering, hydraulic engineering and related disciplines.
Trials and Tribulations of Life on an Active Subduction Zone:
Author: Shahin Dashtgard
Publisher: Geological Society of America
ISBN: 0813700388
Category : Science
Languages : en
Pages : 236
Book Description
"Nine field guides explore diverse topics such as urban geology and geoheritage in Metro Vancouver, the processes and postglacial adjustments of the Cordilleran Ice Sheet, and human interaction and adaptation to geological and climate changes in British Columbia"--
Publisher: Geological Society of America
ISBN: 0813700388
Category : Science
Languages : en
Pages : 236
Book Description
"Nine field guides explore diverse topics such as urban geology and geoheritage in Metro Vancouver, the processes and postglacial adjustments of the Cordilleran Ice Sheet, and human interaction and adaptation to geological and climate changes in British Columbia"--
Channel-conveyance capacity, channel change, and sediment transport in the lower Puyallup, White, and Carbon Rivers, western Washington
Author: Jonathan A. Czuba
Publisher: U.S. Department of the Interior, U.S. Geological Survey
ISBN:
Category :
Languages : en
Pages : 120
Book Description
Draining the volcanic, glaciated terrain of Mount Rainier, Washington, the Puyallup, White, and Carbon Rivers convey copious volumes of water and sediment down to Commencement Bay in Puget Sound. Recent flooding in the lowland river system has renewed interest in understanding sediment transport and its effects on flow conveyance throughout the lower drainage basin. Bathymetric and topographic data for 156 cross sections were surveyed in the lower Puyallup River system by the U.S. Geological Survey (USGS) and were compared with similar datasets collected in 1984. Regions of significant aggradation were measured along the Puyallup and White Rivers. Between 1984 and 2009, aggradation totals as measured by changes in average channel elevation were as much as 7.5, 6.5, and 2 feet on the Puyallup, White, and Carbon Rivers, respectively. These aggrading river sections correlated with decreasing slopes in riverbeds where the rivers exit relatively confined sections in the upper drainage and enter the relatively unconstricted valleys of the low-gradient Puget Lowland. Measured grain-size distributions from each riverbed showed a progressive fining downstream. Analysis of stage-discharge relations at streamflow-gaging stations along rivers draining Mount Rainier demonstrated the dynamic nature of channel morphology on river courses influenced by glaciated, volcanic terrain. The greatest rates of aggradation since the 1980s were in the Nisqually River near National (5.0 inches per year) and the White River near Auburn (1.8 inches per year). Less pronounced aggradation was measured on the Puyallup River and the White River just downstream of Mud Mountain Dam. The largest measured rate of incision was measured in the Cowlitz River at Packwood (5.0 inches per year). Channel-conveyance capacity estimated using a one-dimensional hydraulic model decreased in some river reaches since 1984. The reach exhibiting the largest decrease (about 20–50 percent) in channel-conveyance capacity was the White River between R Street Bridge and the Lake Tapps return, a reach affected by recent flooding. Conveyance capacity also decreased in sections of the Puyallup River. Conveyance capacity was mostly unchanged along other study reaches. Bedload transport was simulated throughout the entire river network and consistent with other observations and analyses, the hydraulic model showed that the upper Puyallup and White Rivers tended to accumulate sediment. Accuracy of the bedload-transport modeling, however, was limited due to a scarcity of sediment-transport data sets from the Puyallup system, mantling of sand over cobbles in the lower Puyallup and White Rivers, and overall uncertainty in modeling sediment transport in gravel-bedded rivers. Consequently, the output results from the model were treated as more qualitative in value, useful in comparing geomorphic trends within different river reaches, but not accurate in producing precise predictions of mass of sediment moved or deposited. The hydraulic model and the bedload-transport component were useful for analyzing proposed river-management options, if surveyed cross sections adequately represented the river-management site and proposed management options. The hydraulic model showed that setback levees would provide greater flood protection than gravel-bar scalping after the initial project construction and for some time thereafter, although the model was not accurate enough to quantify the length of time of the flood protection. The greatest hydraulic benefit from setback levees would be a substantial increase in the effective channel-conveyance area. By widening the distance between levees, the new floodplain would accommodate larger increases in discharge with relatively small incremental increases in stage. Model simulation results indicate that the hydraulic benefit from a setback levee also would be long-lived and would effectively compensate for increased deposition within the setback reach from increased channel-conveyance capacity. In contrast, the benefit from gravel-bar scalping would be limited by the volume of material that could be removed and the underlying hydraulics in the river section that would be mostly unaffected by scalping. Finally, the study formulated an explanation of the flooding that affected Pacific, Washington, in January 2009. Reduction in channel-conveyance capacity of about 25 percent at the White River near Auburn streamflow-gaging station between November 2008 and January 2009 was caused by rapid accumulation of coarse-grained sediment just downstream of the gage, continuing an ongoing trend of aggradation that has been documented repeatedly.
Publisher: U.S. Department of the Interior, U.S. Geological Survey
ISBN:
Category :
Languages : en
Pages : 120
Book Description
Draining the volcanic, glaciated terrain of Mount Rainier, Washington, the Puyallup, White, and Carbon Rivers convey copious volumes of water and sediment down to Commencement Bay in Puget Sound. Recent flooding in the lowland river system has renewed interest in understanding sediment transport and its effects on flow conveyance throughout the lower drainage basin. Bathymetric and topographic data for 156 cross sections were surveyed in the lower Puyallup River system by the U.S. Geological Survey (USGS) and were compared with similar datasets collected in 1984. Regions of significant aggradation were measured along the Puyallup and White Rivers. Between 1984 and 2009, aggradation totals as measured by changes in average channel elevation were as much as 7.5, 6.5, and 2 feet on the Puyallup, White, and Carbon Rivers, respectively. These aggrading river sections correlated with decreasing slopes in riverbeds where the rivers exit relatively confined sections in the upper drainage and enter the relatively unconstricted valleys of the low-gradient Puget Lowland. Measured grain-size distributions from each riverbed showed a progressive fining downstream. Analysis of stage-discharge relations at streamflow-gaging stations along rivers draining Mount Rainier demonstrated the dynamic nature of channel morphology on river courses influenced by glaciated, volcanic terrain. The greatest rates of aggradation since the 1980s were in the Nisqually River near National (5.0 inches per year) and the White River near Auburn (1.8 inches per year). Less pronounced aggradation was measured on the Puyallup River and the White River just downstream of Mud Mountain Dam. The largest measured rate of incision was measured in the Cowlitz River at Packwood (5.0 inches per year). Channel-conveyance capacity estimated using a one-dimensional hydraulic model decreased in some river reaches since 1984. The reach exhibiting the largest decrease (about 20–50 percent) in channel-conveyance capacity was the White River between R Street Bridge and the Lake Tapps return, a reach affected by recent flooding. Conveyance capacity also decreased in sections of the Puyallup River. Conveyance capacity was mostly unchanged along other study reaches. Bedload transport was simulated throughout the entire river network and consistent with other observations and analyses, the hydraulic model showed that the upper Puyallup and White Rivers tended to accumulate sediment. Accuracy of the bedload-transport modeling, however, was limited due to a scarcity of sediment-transport data sets from the Puyallup system, mantling of sand over cobbles in the lower Puyallup and White Rivers, and overall uncertainty in modeling sediment transport in gravel-bedded rivers. Consequently, the output results from the model were treated as more qualitative in value, useful in comparing geomorphic trends within different river reaches, but not accurate in producing precise predictions of mass of sediment moved or deposited. The hydraulic model and the bedload-transport component were useful for analyzing proposed river-management options, if surveyed cross sections adequately represented the river-management site and proposed management options. The hydraulic model showed that setback levees would provide greater flood protection than gravel-bar scalping after the initial project construction and for some time thereafter, although the model was not accurate enough to quantify the length of time of the flood protection. The greatest hydraulic benefit from setback levees would be a substantial increase in the effective channel-conveyance area. By widening the distance between levees, the new floodplain would accommodate larger increases in discharge with relatively small incremental increases in stage. Model simulation results indicate that the hydraulic benefit from a setback levee also would be long-lived and would effectively compensate for increased deposition within the setback reach from increased channel-conveyance capacity. In contrast, the benefit from gravel-bar scalping would be limited by the volume of material that could be removed and the underlying hydraulics in the river section that would be mostly unaffected by scalping. Finally, the study formulated an explanation of the flooding that affected Pacific, Washington, in January 2009. Reduction in channel-conveyance capacity of about 25 percent at the White River near Auburn streamflow-gaging station between November 2008 and January 2009 was caused by rapid accumulation of coarse-grained sediment just downstream of the gage, continuing an ongoing trend of aggradation that has been documented repeatedly.
Ecological Responses at Mount St. Helens: Revisited 35 years after the 1980 Eruption
Author: Charles M. Crisafulli
Publisher: Springer
ISBN: 1493974513
Category : Science
Languages : en
Pages : 340
Book Description
This book builds on existing work exploring succession, disturbance ecology, and the interface between geophysical and biological systems in the aftermath of the 1980 eruptions of Mount St. Helens. The eruption was dramatic both in the spatial extent of impacts and the range of volcanic disturbance types and intensities. Complex geophysical forces created unparalleled opportunities to study initial ecological responses and long-term succession processes that occur in response to a major contemporary eruption across a great diversity of ecosystems—lowland to alpine forests, meadows, lakes, streams, and rivers. These factors make Mount St. Helens an extremely rich environment for learning about the ecology of volcanic areas and, more generally, about ecosystem response to major disturbance of many types, including land management. Lessons about ecological recovery at Mount St. Helens are shaping thought about succession, disturbance ecology, ecosystem management, and landscape ecology. In the first five years after the eruption several syntheses documented the numerous, intensive studies of ecological recovery. The 2005 volume “Ecological Responses to the 1980 Eruption of Mount St. Helens” (Springer Publishing) was the first ecological synthesis since 1987 of the scores of ecological studies underway in the area. More than half of the world’s published studies on plant and animal responses to volcanic eruptions have taken place at Mount St. Helens. The 25-year synthesis, which generally included investigations (i.e., data) from 1980-2000, made it possible to more thoroughly analyze initial stages of ecological responses and to test the validity of early interpretations and the duration of early phenomena. And 35 years after the eruption, it is time for many of the scientists working in the first three-decade, post-eruption period to pass the science baton to the next generation of scientists to work at Mount St. Helens, and a synt hesis a t this time of transfer of responsibility to a younger cohort of scientists will be an enormous asset to the continuation of work at the volcano.
Publisher: Springer
ISBN: 1493974513
Category : Science
Languages : en
Pages : 340
Book Description
This book builds on existing work exploring succession, disturbance ecology, and the interface between geophysical and biological systems in the aftermath of the 1980 eruptions of Mount St. Helens. The eruption was dramatic both in the spatial extent of impacts and the range of volcanic disturbance types and intensities. Complex geophysical forces created unparalleled opportunities to study initial ecological responses and long-term succession processes that occur in response to a major contemporary eruption across a great diversity of ecosystems—lowland to alpine forests, meadows, lakes, streams, and rivers. These factors make Mount St. Helens an extremely rich environment for learning about the ecology of volcanic areas and, more generally, about ecosystem response to major disturbance of many types, including land management. Lessons about ecological recovery at Mount St. Helens are shaping thought about succession, disturbance ecology, ecosystem management, and landscape ecology. In the first five years after the eruption several syntheses documented the numerous, intensive studies of ecological recovery. The 2005 volume “Ecological Responses to the 1980 Eruption of Mount St. Helens” (Springer Publishing) was the first ecological synthesis since 1987 of the scores of ecological studies underway in the area. More than half of the world’s published studies on plant and animal responses to volcanic eruptions have taken place at Mount St. Helens. The 25-year synthesis, which generally included investigations (i.e., data) from 1980-2000, made it possible to more thoroughly analyze initial stages of ecological responses and to test the validity of early interpretations and the duration of early phenomena. And 35 years after the eruption, it is time for many of the scientists working in the first three-decade, post-eruption period to pass the science baton to the next generation of scientists to work at Mount St. Helens, and a synt hesis a t this time of transfer of responsibility to a younger cohort of scientists will be an enormous asset to the continuation of work at the volcano.
Natural Hazards in El Salvador
Author: William Ingersoll Rose
Publisher: Geological Society of America
ISBN: 9780813723754
Category : Reference
Languages : en
Pages : 512
Book Description
Publisher: Geological Society of America
ISBN: 9780813723754
Category : Reference
Languages : en
Pages : 512
Book Description
Preliminary Bibliography and Index of the Geology and Mineral Resources of Washington, 1991-1995
Author:
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 364
Book Description
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 364
Book Description
Geomorphology of the Lower Copper River, Alaska
Author: Timothy P. Brabets
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 102
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 102
Book Description