28 Apr 2020

PUBLICATION NOTIFICATION: Evaluation of Rapid-Setting Cementitious Materials and Testing Protocol for Airfield Spall Repair

Abstract: The rapid-setting cementitious material certification program is part of a research effort to assist the U.S. Air Force Civil Engineering Center in the execution of independent testing on select commercially available proprietary products to repair partial-depth spalls in airfield concrete pavements. The purpose of this research was to determine whether the existing requirements for evaluating rapid-repair products for spall repairs were sufficient or further refinement and modifications were needed. This protocol is intended to aid airfield managers and repair teams in the selection of optimal spall repair materials by maintaining a database of approved tested products. This report presents the test methods and results of 26 cementitious rapid-setting repair products tested at the U.S. Army Engineer Research and Development Center in Vicksburg, MS, during 2013 to 2017. An evaluation of these test methods and results, along with the historic database of products tested, led to the development of an updated testing protocol for assessing a material’s suitability for airfield spall repairs. Based on the revised criteria, 10 products were identified as most compatible for partial-depth airfield pavement concrete spall repairs.

27 Apr 2020

PUBLICATION NOTICE: Proceedings from the US Army Corps of Engineers (USACE) and the National Oceanic and Atmospheric Administration (NOAA)–National Ocean Service (NOS): Ecological Habitat Modeling Workshop

ABSRACT: This special report summarizes the activities of the Ecological Habitat Modeling Workshop held April 11–12, 2019, at the US Fish and Wildlife Service (USFWS) Blackwater National Wildlife Refuge Visitors Center in Cambridge, Maryland. The workshop guided 21 participants through the process of conceptualizing, quantifying, evaluating, and communicating ecological responses to inform guidance and management decisions for ecological restoration projects. Working in interactive groups, participants used the restoration work already in progress at nearby Swan Island as the basis for their model development. Over the course of the two-day workshop, participants learned the mechanics and challenges of applying modeling processes to shape the restoration of dynamic ecosystems. Through group work and brainstorming, they identified a number of benchmarks to assess restoration success and future resilience. To accommodate the changeable and often unpredictable natural events that can shape ecosystems, workshop facilitators emphasized building iterative, fluid ecological habitat models. Next steps include publishing this special report and scheduling a follow-up workshop that will include a site visit to Swan Island.

27 Apr 2020

PUBLICATION NOTICE: AIS Data Case Study: River Level and Vessel Approach Variation at Melvin Price Locks and Dam in St. Louis District

ABSRACT: The US Army Corps of Engineers (USACE), St. Louis District (MVS), manages multiple lock and dam structures on the Mississippi River. One of these, Melvin Price Locks and Dam (MPLD), was the subject of at least 12 allision events from downbound (southbound) vessels between January and November 2018 according to US Coast Guard (USCG) records, an unusually high number for this location. In an effort to understand how vessel operations change under varying river conditions, historical river gauge data and historical vessel position data for both upbound (northbound) and downbound (southbound) traffic were examined together to describe general approach paths for vessels at different water levels. Historic tracks for vessels involved in allusion events are not included in this work because of ongoing investigations at the time of publication.

27 Apr 2020

PUBLICATION NOTICE: Benefits of Engineered Habitats to Seasonal Bird Communities on the Savannah Harbor Navigation Project, Dredged Material Containment Areas, 1994-2012

Abstract: This report presents the results of a long-term habitat and trend analyses of bird community data from a monitoring effort conducted on five Dredged Material Containment Areas (DMCAs) from 1994 to 2012. The USACE Savannah District developed and implemented a Long-Term Management Strategy (LTMS) for the DMCAs in 1996 to mitigate lost wetland habitat due to maintenance operations in the Savannah Harbor, and to provide habitat for the floral and faunal communities that otherwise would be available if not for the urban and economic development of the area. Bimonthly surveys were conducted from 1994 to 2012 to assess the effectiveness of the LTMS to provide seasonal habitat for the bird community. Archived quarterly satellite imagery was collected and analyzed from 2001 to 2011 to assess year-round seasonal habitat availability. All bird community data collected were fitted to a negative binomial (mean abundance) or Poisson distribution (mean species richness) and used to assess trends for 180 individual species and 12 species groups for spring, summer, fall, and winter seasons from 1994 to 2012. Results indicate that the Savannah DMCAs support stable to increasing populations of most species and species groups during each season, including many species ranked as regional priority species.

27 Apr 2020

PUBLICATION NOTICE: Investigation into Laboratory Bathymetric Measurement Techniques

ABSTRACT: There is no universally accepted way to accurately and efficiently measure bathymetry in laboratory hydraulic models. Remote sensing techniques can measure bathymetry without making contact with the model, and some remote sensing techniques can measure the bathymetry in laboratory models without draining the water. The four categories of remote sensing technology investigated in this report are echo sounding technology, laser technology, image processing technology, and radar technology. The technology of each category has strengths and limitations, but can be used in the laboratory to measure bathymetry. Echo sounding technology works well in environments with suspended sediment, but the accuracy is reduced by large beam footprints. Laser technology does not perform as well with suspended sediment but can provide high-accuracy bathymetric measurements. Stereophotography, discussed in the image processing technology section, requires optically clear water and can provide very accurate bathymetric mapping. Radar technology can be very helpful when sub-bottom stratigraphy is important. Technology from each of the categories has been scaled for field application to measure bathymetry and submerged coastal structures.

27 Apr 2020

PUBLICATION NOTICE: Evaluation of the Potential Impacts of the Proposed Mobile Harbor Navigation Channel Expansion on the Aquatic Resources of Mobile Bay, Alabama

Abstract: This report assesses potential impacts to aquatic resources resulting from proposed navigation channel expansion activities within Mobile Bay, Alabama. This work was conducted for the U.S. Army Corps of Engineers (USACE) Mobile District, to support development of a supplemental Environmental Impact Statement. Changes in water quality and hydrodynamics were evaluated for potential impacts to benthic macroinvertebrates, wetlands, submerged aquatic vegetation, oysters, and fish. The assessment includes extensive characterization of baseline conditions, evaluation of estimated post-project conditions related to aquatic resource habitat (e.g., changes in salinity, dissolved oxygen). An analysis of potential impacts related to a 0.5-m sea level rise scenario were also evaluated. Results suggest that no substantial impacts in aquatic resources within the study area are anticipated due to project implementation, as the area of greatest potential changes to environmental conditions are already adapted to natural shifts in salinity (and other factors), and to conditions resulting from the existing navigation channel. Although sea level rise has the potential to alter aquatic resource habitats with Mobile Bay, additional impacts related to project implementation remain negligible under the 0.5-m sea level rise scenario.

26 Apr 2020

CRREL, Area Fire Departments and the NH Department Environmental Services work to contain spill

The Cold Regions Research and Engineering Laboratory discovered a Number 2 heating oil leak from a boiler at its facility at approximately 4 p.m., Saturday, April 25. The CRREL facility is located at 72 Lyme Road in Hanover. No injuries have been reported. CRREL, along with the Hanover, Lebanon, Hartford and Norwich Fire Departments and the New Hampshire Department for Environmental Services are working together to contain the spill. Residents are asked to stay away from the area at this time.

23 Apr 2020

PUBLICATION NOTICE: A Comparison of GenCade,  Pelnard-Considere, and LITPACK

PURPOSE: The purpose of this Coastal and Hydraulics Engineering Technical Note (CHETN) is to investigate the basic physics and numerical code of GenCade by running a series of simplified test cases and comparing the results to another numerical shoreline evolution model and an analytical solution. The complementary numerical code is the widely used shoreline evolution model LITPACK. The analytical model is the original solution derived by Pelnard-Considere (1956). The underlying assumption in all three approaches is a beach profile of constant shape so that shoreline change is driven by long-shore transport processes and a combination of independent sediment sources or sinks (e.g., sea level change, subsidence). The CHETN presents a descriptive overview of the theory behind the models followed by an inter-comparison using a set of four test cases involving shoreline change in the vicinity of idealized coastal structures and a beach nourishment. GenCade shows good agreement with LITPACK, and both models compare well to the analytical solution for these idealized cases. The GenCade results indicate that the underlying numerical code and basic physical process are consistent with other widely used shoreline modeling systems.

23 Apr 2020

PUBLICATION NOTICE: Cross-Shore Transport Feature for GenCade

PURPOSE: The purpose of this Coastal and Hydraulics Engineering Technical Note (CHETN) is to introduce a new cross-shore transport capability in GenCade. The cross-shore transport feature is based on a new empirical algorithm that includes wave velocity skewness to calculate the near-bed sediment flux. Validation of the new algorithm was achieved using shoreline position data collected at the US Army Corps of Engineers (USACE) Field Research Facility (FRF) located in Duck, NC. This CHETN presents the theory behind the new cross-shore transport feature and validation using data collected at the FRF. Comparisons with and without the cross-shore feature are presented to demonstrate the improved GenCade performance. The CHETN concludes information that should be considered when using this new feature.

23 Apr 2020

PUBLICATION NOTICE: Conspecific Attraction as a Management Tool for Endangered and At-Risk Species on Military Lands

Abstract: Movements of wildlife species and associated colonization of habitats is often unpredictable, potentially leading to ineffective management and/or interference with military training. Habitat restoration for wildlife management on military lands is a common, yet expensive, response to federal conservation and mitigation mandates, yet viable wildlife populations often fail to become established on restored habitat. Conspecific attraction, using the tendency for individuals of the same species to settle near one another, can be a cost-effective means of attracting animals to newly created or restored habitats. This work demonstrated the use of conspecific attraction as an alternative tool for encouraging colonization of restored habitats by at-risk birds and amphibians. Conspecific attraction was relatively straightforward to employ, but its effectiveness varied among species. We demonstrated clear success in attracting some bird (northern bobwhite; Colinus virginianus) and frog (wood frogs; Lithobates sylvaticus) species into our target areas but other species showed a neutral response. Conspecific attraction presents a cost-effective alternative to current management practices such as translocation or colonization after habitat is created or restored. Only minimal equipment costs (<$300/broad-cast station) and nominal work-hours are required to set up the equipment, and total cost was ~$1,200 per demonstration plot annually.