Bakers Haulover Inlet Management
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CONTROL of .ALLUVIAL RIVERS by STEEL JETTIES By
CONTROL OF .ALLUVIAL RIVERS BY STEEL JETTIES by E. 1. Carlson and R. A. Dodge, Jr. A paper to be presented at The First Water Resources Engineering Conference of The American Society of Civil Engineers, Omaha, Nebraska, May 14-18, 1962 CONTROL OF ALLUVIAL RIVERS BY STEEL JETTIES by E. J. Carlsonl / and R. A. Dodge, Jr. 2 / SYNOPSIS Both field and laboratory studies were conducted to refine the methods used in the design of steel jetty fields for river aline- ment. A set of dimensionless friction head-loss curves, verified by model studies are developed and described. Using the developed curves and reconnaissance field data, a method is given for predict- ing the changes in a riverbed after the designed jetty field is installed. /Head, Sediment Investigations Unit, Hydraulics Branch, Division of Engineering Laboratories, Bureau of Reclamation, Denver, Colorado. 2 /Hydraulic Engineer, Hydraulics Branch, Division of Engineering Laboratories, Bureau of Reclamation, Denver, Colorado. INTRODUCTION Steel jacks and jetties have been used successfully by the Corps of Engineers, highway departments, railway companies, and others to prevent damage to riverbanks, levees, bridge abutments, and other structures. The Bureau of Reclamation and the Corps of Engineers are using them to stabilize the channel of the Rio Grande within the floodway in the Middle Rio Grande Valley. (1)1 / The individual jack unit consists of three angle irons, 12 or 16 feet in length placed at 90° angles in three planes and joined at their cen- ters, Figure 1. Wire is laced through the angle irons in a standard pattern to tie them together. -
Dealing with Erosion: the Spectrum of Coastal Erosion Control Methods
2ND ANNUAL CAPE COASTAL CONFERENCE Linking Science with Local Solutions and Decision-Making Dealing With Erosion: The Spectrum of Coastal Erosion Control Methods Greg Berman (Woods Hole Sea Grant & Cape Cod Cooperative Extension) Photo Credit: Ted Keon Climate Change Impacts In Coastal Environments 34 5 12 Coastal Adaptation On Cape Cod we manage at parcel scale http://www.ipcc.ch/ipccreports/sres/regional/index.php?idp=223 The Spectrum of Coastal Erosion Control Methods Why protect properties……..? Town of Brewster example The Facts The Implications Value = $333,000,000 (don’t want takings) Only ~1% of properties To keep the same revenue, ~3% of town area the tax rate would go from 8.18 to 9.06 but they make ~10% of the real estate taxes or ~$300 per household The Spectrum of Coastal Erosion Control Methods • Do nothing 1. Will system recover by itself? 2. How far is the structure from the water? 3. Grandfathering protects structures (not lawn) before August 10, 1978 Photo Credit: Ann McNichol The Spectrum of Coastal Erosion Control Methods • Do nothing • Vegetation Plant Natives: Root systems stabilize. Take up water. Break the impact of raindrops or wave-splash. Slow down runoff Remove Invasive The Spectrum of Coastal Erosion Control Methods • Do nothing • Vegetation • Re-grade The Spectrum of Coastal Erosion Control Methods • Do nothing Horizontal • Vegetation • Re-grade • Managed retreat V E R T I C A L The Spectrum of Coastal Erosion Control Methods • Do nothing Photo Credit: Ted Keon • Vegetation • Re-grade • Managed retreat • Beach -
River Incision Into Bedrock: Mechanics and Relative Efficacy of Plucking, Abrasion and Cavitation
River incision into bedrock: Mechanics and relative efficacy of plucking, abrasion and cavitation Kelin X. Whipple* Department of Earth, Atmospheric, and Planetary Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 Gregory S. Hancock Department of Geology, College of William and Mary, Williamsburg, Virginia 23187 Robert S. Anderson Department of Earth Sciences, University of California, Santa Cruz, California 95064 ABSTRACT long term (Howard et al., 1994). These conditions are commonly met in Improved formulation of bedrock erosion laws requires knowledge mountainous and tectonically active landscapes, and bedrock channels are of the actual processes operative at the bed. We present qualitative field known to dominate steeplands drainage networks (e.g., Wohl, 1993; Mont- evidence from a wide range of settings that the relative efficacy of the gomery et al., 1996; Hovius et al., 1997). As the three-dimensional structure various processes of fluvial erosion (e.g., plucking, abrasion, cavitation, of drainage networks sets much of the form of terrestrial landscapes, it is solution) is a strong function of substrate lithology, and that joint spac- clear that a deep appreciation of mountainous landscapes requires knowl- ing, fractures, and bedding planes exert the most direct control. The edge of the controls on bedrock channel morphology. Moreover, bedrock relative importance of the various processes and the nature of the in- channels play a critical role in the dynamic evolution of mountainous land- terplay between them are inferred from detailed observations of the scapes (Anderson, 1994; Anderson et al., 1994; Howard et al., 1994; Tucker morphology of erosional forms on channel bed and banks, and their and Slingerland, 1996; Sklar and Dietrich, 1998; Whipple and Tucker, spatial distributions. -
STREAMS and RUNNING WATER Hydrologic Cycle •What Happens to Precipitation STREAM •River, Creek, Etc
STREAMS AND RUNNING WATER Hydrologic Cycle •What happens to precipitation STREAM •River, Creek, etc. • Banks, Bed • Confined to a channel –Except in time of flood •Floodplain •Longtitudinal Profile Headwaters, mouth Cross-profile V-shaped SHEETWASH –Unchanneled, thin sheet of flowing water – Results in Sheet Erosion Drainage Basin •Tributary • Divide • Examples: –Mississippi River – Amazon River Drainage Patterns •As seen from above • Dendritic (most common) • Radial • Trellis- in tilted or folded layered rock Factors affecting stream erosion and deposition •Velocity- –Distribution in cross-section •Gradient –Usually decreases downstream – Effect on deposition and erosion •Channel shape and roughness • Discharge- –Volume of water moving past a place in time •Usually given as cubic feet per second (cfs) –Usually increases downstream •Discharge- –Volume of water moving past a place in time •Usually given as cubic feet per second (cfs) –Usually increases downstream American River Discharge •In Sacramento: • Average 3,741 c.f.s. • Usual Range: –Winter 9,000 cfs – Last drought 250 cfs •1986 flood 130,000 cfs Stream Erosion •Hydraulic action • Solution- Dissolves rock • Abrasion (by sand and gravel) –Potholes •Deepens valley by eroding river bed • Lateral erosion of banks on outside of curves Transportation of Sediment •Bed load • Suspended load • Dissolved load Deposition •Bars- –moved in floods – deposited as water slows – Placer Deposits (gold, etc.) – Braided Streams •heavy load of sand and gravel • commonly from glacier outwash streams -
Beach Nourishment Effects Østerstrand Fredericia - Denmark 2017
Beach Nourishment Effects Østerstrand Fredericia - Denmark 2017 Juni 2020 Project Building with Nature (EU-InterReg) Start date 01.11.2016 End date 01.07.2020 Project manager (PM) Ane Høiberg Nielsen Project leader (PL) Per Sørensen Project staff (PS) Henrik Vinge Karlsson Time registering 402412 Approved date 26.06.2020 Signature Report Beach nourishment effects – Østerstrand, Frederica, Denmark Author Henrik Vinge Karlsson and Per Sørensen Keyword Beach nourishment, Nourishment design, Coastal protection, Building with nature, BWN, Fredericia, Østerstrand. Distribution www.kyst.dk, www.northsearegion.eu/building-with-nature Referred to as Kystdirektoratet (2020), Beach nourishment effects – Østerstrand, Frederica; Lemvig. 2 Beach Nourishment Effects Contents 1. Introduction ................................................................................................. 5 1.1 Description of Study site .............................................................................................................................5 1.2 Division of study stretch..............................................................................................................................7 1.3 Description of Nourishment ......................................................................................................................7 1.4 Research design ..............................................................................................................................................8 1.4.1 Research questions..............................................................................................................................................................................................................................................9 -
River Processes- Erosion, Transportation and Deposition Task 1: for Each of the Processes of Erosion and Transportation Draw a Diagram Show the Process at Work
River Processes- Erosion, Transportation and Deposition Task 1: For each of the processes of erosion and transportation draw a diagram show the process at work In the upper course of the main process is Erosion. This is where the bed and banks of the river are worn away. A river can erode in one of four ways: Process Definition Diagram Hydraulic the sheer force of water hitting the action banks of the river: Abrasion fine material rubs against the riverbank The bank is worn away by a sand- papering action called abrasion, and collapses. This occurs on the outside of meanders. Attrition material is moved along the bed of a river, collides with other material, and breaks up into smaller pieces. Corrosion rocks forming the banks and bed of a river are dissolved by acids in the water. Once the material is eroded it can then be transported by one of four ways, which will depend upon the energy of the river: Process Definition Diagram Traction large rocks and boulders are rolled along the bed of the river. Saltation smaller stones are bounced along the bed of the river Suspension fine material which is carried by the water and which gives the river its 'muddy' colour. Solution dissolved material transported by the river. In the middle and lower course, the land is much flatter, this means that the river is flowing more slowly and has much less energy. The river starts to deposit (drop) the material that it has been carry Deposition Challenge: Add labels onto the diagram to show where all of the processes could be happening in the river channel. -
Experiments on Patterns of Alluvial Cover and Bedrock Erosion in a Meandering Channel Roberto Fernández1, Gary Parker1,2, Colin P
Earth Surf. Dynam. Discuss., https://doi.org/10.5194/esurf-2019-8 Manuscript under review for journal Earth Surf. Dynam. Discussion started: 27 February 2019 c Author(s) 2019. CC BY 4.0 License. Experiments on patterns of alluvial cover and bedrock erosion in a meandering channel Roberto Fernández1, Gary Parker1,2, Colin P. Stark3 1Ven Te Chow Hydrosystems Laboratory, Department of Civil and Environmental Engineering, University of Illinois at 5 Urbana-Champaign, Urbana, IL 61801, USA 2Department of Geology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA 3Lamont Doherty Earth Observatory, Columbia University, Palisades, NY 10964, USA Correspondence to: Roberto Fernández ([email protected]) Abstract. 10 In bedrock rivers, erosion by abrasion is driven by sediment particles that strike bare bedrock while traveling downstream with the flow. If the sediment particles settle and form an alluvial cover, this mode of erosion is impeded by the protection offered by the grains themselves. Channel erosion by abrasion is therefore related to the amount and pattern of alluvial cover, which are functions of sediment load and hydraulic conditions, and which in turn are functions of channel geometry, slope and sinuosity. This study presents the results of alluvial cover experiments conducted in a meandering channel flume of high fixed 15 sinuosity. Maps of quasi-instantaneous alluvial cover were generated from time-lapse imaging of flows under a range of below- capacity bedload conditions. These maps were used to infer patterns -
COLD-BASED GLACIERS in the WESTERN DRY VALLEYS of ANTARCTICA: TERRESTRIAL LANDFORMS and MARTIAN ANALOGS: David R
Lunar and Planetary Science XXXIV (2003) 1245.pdf COLD-BASED GLACIERS IN THE WESTERN DRY VALLEYS OF ANTARCTICA: TERRESTRIAL LANDFORMS AND MARTIAN ANALOGS: David R. Marchant1 and James W. Head2, 1Department of Earth Sciences, Boston University, Boston, MA 02215 [email protected], 2Department of Geological Sciences, Brown University, Providence, RI 02912 Introduction: Basal-ice and surface-ice temperatures are contacts and undisturbed underlying strata are hallmarks of cold- key parameters governing the style of glacial erosion and based glacier deposits [11]. deposition. Temperate glaciers contain basal ice at the pressure- Drop moraines: The term drop moraine is used here to melting point (wet-based) and commonly exhibit extensive areas describe debris ridges that form as supra- and englacial particles of surface melting. Such conditions foster basal plucking and are dropped passively at margins of cold-based glaciers (Fig. 1a abrasion, as well as deposition of thick matrix-supported drift and 1b). Commonly clast supported, the debris is angular and sheets, moraines, and glacio-fluvial outwash. Polar glaciers devoid of fine-grained sediment associated with glacial abrasion include those in which the basal ice remains below the pressure- [10, 12]. In the Dry Valleys, such moraines may be cored by melting point (cold-based) and, in extreme cases like those in glacier ice, owing to the insulating effect of the debris on the the western Dry Valleys region of Antarctica, lack surface underlying glacier. Where cored by ice, moraine crests can melting zones. These conditions inhibit significant glacial exceed the angle of repose. In plan view, drop moraines closely erosion and deposition. -
Avulsion Dynamics in a River with Alternating Bedrock and Alluvial Reaches, Huron River, Northern Ohio (USA)
Open Journal of Modern Hydrology, 2019, 9, 20-39 http://www.scirp.org/journal/ojmh ISSN Online: 2163-0496 ISSN Print: 2163-0461 Avulsion Dynamics in a River with Alternating Bedrock and Alluvial Reaches, Huron River, Northern Ohio (USA) Mark J. Potucek1,2, James E. Evans1 1Department of Geology, Bowling Green State University, Bowling Green, OH, USA 2Arizona Department of Water Resources, Phoenix, AZ, USA How to cite this paper: Potucek, M.J. and Abstract Evans, J.E. (2019) Avulsion Dynamics in a River with Alternating Bedrock and Alluvi- The Huron River consists of alternating bedrock reaches and alluvial reaches. al Reaches, Huron River, Northern Ohio Analysis of historical aerial photography from 1950-2015 reveals six major (USA). Open Journal of Modern Hydrolo- gy, 9, 20-39. channel avulsion events in the 8-km study area. These avulsions occurred in https://doi.org/10.4236/ojmh.2019.91002 the alluvial reaches but were strongly influenced by the properties of the up- stream bedrock reach (“inherited characteristics”). The bedrock reaches Received: December 19, 2018 Accepted: January 20, 2019 aligned with the azimuth of joint sets in the underlying bedrock. One inhe- Published: January 23, 2019 rited characteristic in the alluvial reach downstream is that the avulsion channels diverged only slightly from the orientation of the upstream bedrock Copyright © 2019 by author(s) and channel (range 2˚ - 38˚, mean and standard deviation 12.1˚ ± 13.7˚). A Scientific Research Publishing Inc. This work is licensed under the Creative second inherited characteristic is that avulsion channels were initiated from Commons Attribution International short distances downstream after exiting the upstream bedrock channel reach License (CC BY 4.0). -
The Effects of Longitudinal Differences in Gravel Mobility on the Downstream Fining Pattern in the Cosumnes River, California
The Effects of Longitudinal Differences in Gravel Mobility on the Downstream Fining Pattern in the Cosumnes River, California Candice R. Constantine,1 Jeffrey F. Mount, and Joan L. Florsheim Department of Geological Sciences, University of California, Davis, California 95616, U.S.A. (e-mail: [email protected]) ABSTRACT Downstream fining in the Cosumnes River is partially controlled by longitudinal variation in sediment mobility linked to changes in cross-sectional morphology. Strong fining occurs where the channel is self-formed with section- averaged bankfull dimensionless shear stress (t∗ ) near the threshold of motion (ca. 0.031), allowing for size-selective transport. In contrast, fining is minimal in confined reaches wheret∗ is generally greater than twice the threshold value and transport is nonselective. Downstream fining is best described by a model that depicts fining in discrete intervals separated by a segment in which equal mobility of bed material accounts for the lack of diminishing grain size. Introduction Reduction in the size of bed material with distance 1980; Rice and Church 1998; Rice 1999) or anthro- downstream is commonly observed in gravel-bed pogenic channel modifications (Surian 2002). rivers. Researchers have attributed this feature, The relative importance of sorting and abrasion termed “downstream fining,” to the processes of in determining the diminution coefficient depends selective sorting (Ashworth and Ferguson 1989; on the system in question, particularly on the na- Ferguson and Ashworth 1991; Paola et al. 1992; Fer- ture of material in transport (Bradley 1970; Parker guson et al. 1996; Seal et al. 1997) and abrasion 1991; Werrity 1992; Kodama 1994a, 1994b) and (Bradley 1970; Schumm and Stevens 1973; Werrity whether sediment discharge is limited by transport 1992; Kodama 1994a, 1994b). -
COASTAL HAZARDS Too Many People Living Too Close to the Edge of a Rising Sea
COASTAL HAZARDS Too Many People Living Too Close To The Edge Of A Rising Sea A Growing Challenge For The 21st Century This Report Is Part Of The Ocean On The Edge Series Produced By The Aquarium Of The Pacific As Products Of Its National Conference—Ocean On The Edge: Top Ocean Issues, May 2009 2 COASTAL HAZARDS Ocean on the Edge: Top Ocean Issues Making Ocean Issues Come Alive for the Public The conference brought together leading marine scientists and engineers, policy-makers, film-makers, exhibit designers, informal science educators, journalists and communicators to develop a portfolio of models for communicating major ocean issues to the public. This report is one of a series of reports from that conference. The reports include: Coastal Hazards, Marine Ecosystems and Fisheries, Pollution in the Ocean, and Critical Condition: Ocean Health and Human Health. There is also a series of briefer reports on film-making, kiosk messaging design, and communicating science to the public. All reports are available at www.aquariumofpacific.org COASTAL HAZARDS 3 4 COASTAL HAZARDS Acknowledgements Support for the “Ocean on the Edge Conference: Issues” held in May 2009, at Long Beach Top Ocean Issues” was provided by NOAA, Convention Center. Participants in the the National Science Foundation, Southern Coastal Hazards workshop session included: California Edison, SAVOR, the Long Beach Dr. Robert Dean, Dr. R. A. Dalrymple, Dr. Convention Center, and the Aquarium of the Conrad C. Lautenbacher, Jr., Dr. Jerry R. Pacific. Schubel, and Dana Swanson. Sandy Eslinger was the facilitator of the session. Leah Young We are grateful to the Conference’s National and Margaret Schubel were the rapporteurs. -
Mitigation of Channel Shoaling at a Sheltered Inlet Subject to Flood Gate Operations
Journal of Marine Science and Engineering Article Mitigation of Channel Shoaling at a Sheltered Inlet Subject to Flood Gate Operations Laura Lemke * , Matthew S. Janssen and Jon K. Miller Coastal Engineering Research Group, Davidson Laboratory, Stevens Institute of Technology, Hoboken, NJ 07030, USA; [email protected] (M.S.J.); [email protected] (J.K.M.) * Correspondence: [email protected] Received: 30 September 2020; Accepted: 29 October 2020; Published: 31 October 2020 Abstract: A comprehensive case study of Keansburg Inlet (New Jersey, USA) is presented with the objective of evaluating inlet management alternatives and assessing the influence of an operational flood gate on channel shoaling. The goal of the research is determining the most effective strategy for minimizing the frequency of maintenance dredging. This study compares the effectiveness of (1) traditional structural solutions; (2) modified dredging templates; and (3) assesses the influence of the flood gate operations during conditions representative of a typical year. Alternative analysis is completed using a coupled hydrodynamic–wave model (Delft3D-Flexible Mesh (FM)) with Real Time Control to simulate morphological changes. The model was calibrated and evaluated using collected field data. Water levels are reproduced within 6% of the spring tide range with lag times less than 20 min. The model results and observations suggest sediment transport is dominated by wave action with pronounced variations in dominant wave direction. The results indicate that changes to the operational dredging, or what the authors have termed broadly as “adaptive dredging techniques”, appear to deliver the most promising improvement. Model results suggest that the current operational procedures of the flood gate do not significantly alter the channel infilling rates and patterns during typical (i.e., non-extreme event) conditions.