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2022 ◽  
Author(s):  
Gary Bell ◽  
David Abraham ◽  
Gaurav Savant ◽  
Anthony G. Emiren

The Morganza Floodway and the Atchafalaya Basin, located in Louisiana west of the Mississippi River, were evaluated using a two-dimensional Adaptive Hydraulics model. Prior to this study, Phase 1 and 2 model studies were performed that indicated that the existing floodway may not be able to pass the Project Design Flood discharge of 600,000 cubic feet per second due to levee overtopping. In this study, all elevations of exterior and interior levees were updated with current crest elevations. In addition, the Phase 3 effort evaluated the sensitivity of the floodway’s flow capacity to variations in tree/vegetation density conditions. These adjustments in roughness will improve the understanding of the role of land cover characteristics in the simulated water surfaces. This study also provides a number of inundation maps corresponding to certain flows through the Morganza Control Structure.


2022 ◽  
Author(s):  
Joseph Dunbar

Six geodetic datums have been used by the US Army Corps of Engineers (USACE), Mississippi River Commission (MRC), for river surveys in the Lower Mississippi Valley (LMV). These legacy elevation datums are the Cairo datum, the Memphis datum, the Mean Gulf Level (MGL), the Mean Sea Level (MSL), the National Geodetic Vertical Datum (NGVD) 1929, and the North American Vertical Datum 1988 (NAVD88). The official geodetic datum currently prescribed by the USACE is NAVD88 (USACE 2010). In addition to these different geodetic datums, hydraulic datums are in use by the USACE for rivers, lakes, and reservoir systems. Hydrographic surveys from the Mississippi River are typically based on a low water pool or discharge reference, such as a low water reference plane (LWRP), an average low water plane (ALWP), or a low water (LW) plane. The following technical note is intended to provide background information about legacy datums used in the LMV to permit comparison of historic maps, charts, and surveys pertaining to the Mississippi River in the LMV. The purpose of this report is to provide background information and history of different published horizontal and vertical datums used for presentation of hydrographic survey data from the Mississippi River. The goal is to facilitate understanding of differences with comparison to other historic surveys for change-detection studies along the river. Conversion values are identified herein for the earlier surveys where appropriate, and methods are presented here to evaluate the differences between earlier and later charts and maps. This report is solely intended to address the LMV area and historic surveys made there. This note is not applicable to areas outside of the LMV. Throughout this technical note, historic hydrographic surveys and data from the Memphis, TN, to Rosedale, MS, reach will be used as examples of features of interest for discussion purposes. Selected historic hydrographic survey sheets at Helena, AR, are included as Plates 1 to 3 (Appendix C) of this document and will be used as examples for discussion purposes.


Water ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 87
Author(s):  
Hasan Albo-Salih ◽  
Larry W. Mays ◽  
Daniel Che

An application is presented of a new methodology for the real-time operations of river-reservoir systems. The methodology is based upon an optimization/simulation modeling approach that interfaces optimization with a one and/or two-dimensional unsteady flow simulation model (U.S. Army Corps of Engineers HEC-RAS). The approach also includes a model for short-term rainfall forecasting, and the U.S. Army Corps of Engineers HEC-HMS model for rainfall-runoff modeling. Both short-term forecasted rainfall in addition to gaged streamflow data and/or NEXRAD (Next-Generation Radar) can be implemented in the modeling approach. The optimization solution methodology is based upon a genetic algorithm implemented through MATLAB. The application is based upon the May 2010 flood event on the Cumberland River system in the USA, during which releases from Old Hickory dam caused major flooding in the downstream area of Nashville, TN, USA, and allowed the dam to be placed in an emergency operational situation. One of the major features of the modeling effort and the application presented was to investigate the use of different unsteady flow modeling approaches available in the HEC-RAS, including one-dimensional (1D), two-dimensional (2D), and the combined (1D/2D) approach. One of the major results of the application was to investigate the use the different unsteady flow approaches in the modeling approach. The 2D unsteady flow modeling, based upon the diffusion wave approach, was found to be superior for the application to the Cumberland River system. The model application successfully determined real-time operations that would have maintained the flood water surface elevations at the downstream control point in Nashville below the 100-year return period river water surface and maintaining the gate openings at the Old Hickory Dam from reaching an emergency operational situation, which could have caused major losses at the dam.


2022 ◽  
Vol 73 (1-2) ◽  
pp. 5-14
Author(s):  
Lenka Kločková ◽  
Roman Štér

The purpose of this text is to map out the vicissitudes in the life of the Evangelical clergyman Jan Jelínek on the basis of the sources available, in a bid to foster awareness of this prominent personage in the public realm and preserve his memory for future generations. Jan Jelínek was born in 1912 in Zelov (present-day Poland) to Czech exiles. Initially he worked as an accountant in the Jan Sláma company in Zelov, later graduating from the Missionary School in Olomouc and becoming a preacher. In the years 1937 – 1944 he served as preacher in the Czech village of Kupičov in Volhynia. During World War II he helped the persecuted, hiding Jews from the Germans, and Ukrainians and Poles from Bandera’s followers. In 1944 he and his wife joined the First Czechoslovak Army Corps in the USSR. In January 1958 he was arrested by the StB (the secret police of the Communist Czechoslovak state), and following three months of detention on remand, was sentenced to two years in prison for sedition and opposition to the establishment of the JZD (a network of Czech collective farms). He was released in 1960. Until his retirement in 1972, he worked as a labourer in the Paints and Varnishes company. Jan Jelínek died in Prague in 2009. On 28 October 2019 president Miloš Zeman posthumously decorated him with the Order of Tomáš Garrigue Masaryk, Class I.


Significance They have started by renaming the old army corps and beginning to retrain Taliban combatants. In adopting the trappings of a conventional army, they have made their men wear uniform and held military parades. The aim is to show neighbouring countries that the Taliban government is running a real state with appropriate standards for its security forces. Impacts Neighbouring states will be reassured by an army that resembles its predecessor and has no real capabilities beyond domestic security. The Taliban have limited capacity to absorb and use new equipment for now, even if some donor were willing to provide it. Limited help may be available: Chinese, Russian and Pakistan military trainers and advisers are reportedly present.


2021 ◽  
Author(s):  
Johannes Wibowo ◽  
Jamie López-Soto

This report summarizes the results of eight field Jet Erosion Tests (JETs) performed on Benbrook Dam, TX. The results from these tests will be used by the U.S. Army Corps of Engineers, Fort Worth District, in assessments of the erosion resistance of the Benbrook Dam with regards to possible overtopping by extreme flooding. The JETs were performed at four different locations, i.e., two locations at the lowest crest elevation and two locations at the mid-slope face of the downstream embankment. Variations in estimated critical hydraulic shear stress and erosion rate values may have been caused by differences in soil composition, i.e., when the material changed from silt/sand to clay. The resulting values of the Erodibility Coefficient, Kd, and Critical Stress, τc, are very useful information in assessing the stability of Benbrook Dam during an overtopping event. Because of the observed natural variability of the materials, combining the erosion parameters presented in this report with the drilling logs and local geology will be imperative for assessing erosion-related failure modes of Benbrook Dam.


2021 ◽  
Author(s):  
Christopher Haring

The purpose of this review is to highlight LiDAR data usage for geomorphic studies and compare to other remote sensing technologies. This review further identifies survey efficiencies and issues that can be problematic in using LiDAR digital elevation models (DEMs) in completing surveys and geomorphic analysis. US Army Corps of Engineers (USACE) geospatial data collection guidance (EM 1110-1-1000) (USACE 2015) aligns with the American Society for Photogrammetry and Remote Sensing Positional Accuracy Standards for Digital Geospatial Data (ASPRS 2014). Geomorphic assessment technologies are rapidly evolving, and LiDAR data collection methods are at the forefront. The FluvialGeomorph (FG) toolbox, developed to support USACE watershed planning, is a recent example of the use of LiDAR high-resolution terrain data to provide a new, efficient approach for rapid watershed assessments (Haring et al. 2020; Haring and Biedenharn 2021). However, there are advantages and disadvantages in using LiDAR data compared to other remote sensing technologies and traditional topographic field survey methods.


2021 ◽  
Vol 958 (1) ◽  
pp. 012021
Author(s):  
A Jara ◽  
T Y Quispe ◽  
L F Castillo

Abstract The damage assessment caused by floods, earthquakes, hurricanes among others phenomenons in the world are analyzed with methodologies such as “Vulnerability curves”. In Peru, disasters caused by hyperconcentrated flows are alarming due to a climatic variability such as the “El Niño Costero” phenomenon. Therefore, this research has developed vulnerability curves for 1 and 2-story confined masonry buildings in Urb. San Idelfonso, Ica - Peru; linking the variables: flow depth, associated with the event produced by heavy rains at the top of the “Quebrada Cansas” caused by the “El Niño Costero” phenomenon in 2017, and the percentage of the damage based on the methodology of the United States Army Corps of Engineers (USACE), whose formula is the repair value and total building value. The monetary amounts and items of the buildings are obtained from the RM 415-2017-VIVIENDA of the Ministry of Housing, Construction and Sanitation of Peru. The process consisted of hydrological modeling in HEC-HMS, hydraulic modeling in FLO-2D, damage percentage estimate and vulnerability curves production. Finally, the vulnerability curves for hyperconcentrated flows were contrasted with similar studies regarding curves for flooding and debris flow. The results of the investigation showed that the “El Niño Costero” phenomenon in 2017 had an economic impact of at least 1.3 million soles in Urb. San Idelfonso. In addition, at least 24 buildings had a complete damage and 21 buildings an extensive damage.


Author(s):  
Mikhail Veber

This article is dedicated to the history of the Russian Orthodox Church during the revolutionary disturbances of 1917 and the Russian Civil War. The subject of this research is the the history of military clergy of the Kolchak Army. The article introduced into the scientific discourse the report of the dean of the 4th Orenburg Army Corps of the Southern Army of the Armed Forces of Admiral A. V. Kolchak –  archpriest Stefan Vasilyevich Kaverznev on the activity of military clergy of the corps in August – September of 1919. This is a valuable historical source that contains records on staff composition of regimental priests of the 4th Orenburg Army Corps, as well as reveals the engagement of military priests in propaganda activity among the soldiers and officers of the corps. The report of the archpriest S. V. Kaverznev provides valuable information on the history of military operations of the 4th Orenburg Army Corps in summer of 1919, which ended with its defeat and escape to the Turgai Steppe. The article also publishes the formal request of the archpriest S. V. Kaverznev on the emergency situation that took place in the 4th Orenburg Army Corps – desertion of the regimental priest of the 6th Syzran Rifle Regiment Vasily Yaremenko, who joined the Reds in early September of 1919. The author believes that this document testifies to the escalated symptoms that led to decomposition of the Kolchak Army in the autumn of 1919.


Water Policy ◽  
2021 ◽  
Vol 23 (S1) ◽  
pp. 174-187
Author(s):  
Lewis E. Link

Abstract Following Hurricane Katrina, the US Army Corps of Engineers, supported in part by the risk and reliability analysis conducted by the Interagency Performance Evaluation Task Force (IPET), made a major shift from ‘protection’ to ‘risk reduction’ as the principal goal in flood mitigation. The mitigation of the flood risk in Southeast Louisiana was embodied in the design and construction of the ‘Hurricane and Storm Damage Risk Reduction System’, the post-Katrina initiative for New Orleans flood mitigation. It also spawned a major overhaul of many of the Corps of Engineers’ technical guidance and engineering practice documents, incorporating risk as a key measure in the planning and design processes. The criteria applied for the design of the HSDRRS are discussed, with summaries of the associated major changes in Corps engineering guidance and practice relevant to flood mitigation.


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