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Northern Neck Regional Shallow Draft Channel Dredging Plan: Initial Phase
Get PDFThe purpose of this project is to develop a regional dredging program for the localities of the Northern Neck. This report encompasses Phase 1 of the project, which included creating a database of waterbodies in Lancaster, Northumberland, Richmond, and Westmoreland Counties and the Town of Colonial Beach along the Potomac and Rappahannock Rivers and Chesapeake Bay. Generally, these waterbodies can be categorized into three basic types of shallow draft channels: federally-authorized to include aids to navigation (ATONS), non-federal with ATONS, and non-federal without ATONs. Along the Northern Neck, presently identified, are 13 federal channels, 37 non-federal channels in creeks with ATONs, and 92 in creeks without defined channels or ATONs, for a total of 142 waterbodies. Additional non-federal creeks, coves, branches, and ponds (all are interchangeably identified as waterbodies in this report) occur in these localities, but the analysis was limited to waterbodies that had some residential or economic usage. These waterbodies occur in Lancaster (35 waterbodies), Northumberland (67 waterbodies), Richmond (4 waterbodies), and Westmoreland (31 waterbodies) counties. To avoid double counting of waterbodies, 5 additional waterbodies that are located on the boundaries of these counties were attributed to just one county for this report. These waterbodies have been grouped within one of their boundary counties bringing the number of waterbodies in Lancaster to 38 and Westmoreland to 33. Physical parameter data was collected or created for each of these waterbodies. These data included creek mouth morphology, amount of shoaling in the waterbody mouth, waterbody type (primary, secondary, etc.), water surface area, combined shoreline length, historical (1971- 2020) and current (2016-2020) SAV presence, private and public oyster lease presence and the amount of area they cover, number of remotely-sensed coastal structures such as piers, marinas, boat ramps, and verified economic facilities such as marinas and other mooring places, resource, seafood related, and transportation facilities that impact the locality’s economics. Utilizing the collected data, the steps that localities need to take for additional data collection to develop a dredging project were outlined, and recommendations were made for additional regional management considerations for use in Phases 2 and 3. Finally, next steps were suggested. By creating a regional program for dredging of shallow water, localities can save time, effort, and money. Such a program also provides ways for localities to plan for the utilization of dredge material to combat repetitive flooding and improve coastal resiliency.Virginia Institute of Marine Scienc
An Investigation Of The Quality Of Performance Assessments And Implications Of A Grassroots Approach To Accountability Reform
No full textIn 2014 the Virginia General Assembly passed legislation replacing end-of-course, multiple-choice assessments with locally developed alternative assessments in five courses, including two middle school social studies courses. This policy allowed Virginia school divisions the autonomy to develop the format, quantity, and focus of their assessments to meet state accountability. Given the grassroots nature of this policy, there has been little oversight of these local alternative assessments (LAAs). Thus, this exploratory study sought to gain insight into how divisions approached the process of preparing for and developing local alternative assessments and Balanced Assessment Plans, as well as the quality of the assessments created. Through a professional referral sampling process 12 divisions were interviewed and submitted two assessments each to be evaluated against the Virginia Quality Criteria Tool for Performance Assessments (VQCT). The divisions in the study responded to the autonomy granted by the state by first engaging in on-going, quality professional development to build teacher capacity. Using a variety of templates and the VQCT, divisions involved teachers in the process of developing the set of LAAs. The division assessments focus on writing prompts centered around tasks authentic to the social studies which require deeper-learning competencies by students, but the structure of the implementation of the assessments are less consistent potentially lessening the quality of the assessments. The work of these divisions suggest that the success of a grassroots performance assessment policy requires quality, on-going professional development and thoughtful analysis of the assessments and their alignment to desired learning goals.EducationDoctor of Philosophy (Ph.D.
Aerial surveys of the York Haven nature-like fishway project for nesting bald eagles: 2023 breeding season
No full textObjectives for conducting eagle surveys near York Haven nature-like fishway project are: 1) to document the location, condition, and status, of nesting pairs on lands within an approximate 0.5 mile buffer of proposed construction activities along with lands associated with Three Mile Island and the York Haven hydroelectric plant; 2) to provide updated information to pertinent parties; and 3) to increase our understanding of bald eagle natural history in the upper Chesapeake Bay Watershed
Rates and drivers of benthic respiration in an Arctic coastal lagoon
No full textArctic-wide average temperatures have increased at four times the global rate, resulting in increasing freshwater flow, permafrost thaw, coastal erosion, and decreasing ice cover, which correspond to increased organic matter (OM) inputs to coastal systems. Coastal lagoons are located along the gradient from land to sea and they act as an intermediary bioreactor that processes terrestrial inputs and lagoon production before export to the ocean. Within the lagoons, sediments play a key role in carbon cycling as the site of aerobic and anaerobic respiration of OM. To better understand the role of coastal lagoons in Arctic carbon export, I analyzed sediment characteristics and respiration at 10 stations in Elson Lagoon, Alaska in August 2022. Samples were collected as part of the Beaufort Lagoon Ecosystem Long Term Ecological Research program, including 6 shallow (less than 1m) and 4 deep (greater than 2m) stations. At each station, 1 sediment core was sectioned by depth to analyze for grain size (GS), porosity, and OM content. A second sediment core was used to measure benthic respiration rates by analyzing oxygen microprofiles. In Elson Lagoon, respiration was directly related to each of the sediment characteristics measured. Spatial variability was observed between shallow (20 ± 3 μmol O2 m-2 h-1) and deep (59 ± 11 μmol O2 m-2 h-1) stations in respiration rate which aligned with my observation that deep stations were characterized by a lower average GS (662 ± 10 μm), and higher porosity (50 ± 3%) and OM (8.6 ± 0.2%) compared to shallow station GS (123 ± 20 μm), porosity (23 ± 2%), and OM (3.4 ± 0.5%). Understanding drivers of respiration in Elson Lagoon is important to understand how the ecosystem is functioning, especially with the changing Arctic environment.Geolog
Oyster Morphology in Middle Woodland Middens and Late Woodland Pits at the Shelly Archaeological Site (Southeastern Virginia)
No full textThe Shelly archaeological site (44GL318) is located along the York River across from the Kiskiak site (44YO2) and was inhabited from the Late Archaic to Late Woodland periods (2500 B.C. – 1650 A.D.). The Department of Historic Resources (DHR) excavated a shell midden dated to the Middle Woodland period (250 A.D. – 900 A.D.), as well as two pit features dated to the Late Woodland period (900 A.D. – 1650 A.D.). Middens are areas of shell deposited over a long period of time of discarded shell from daily meals, whereas pit features represent single events such as feasts. This study analyzes the morphology of the oysters excavated from these features to make inferences about whether the people at Shelly were harvesting intertidal or subtidal oysters for everyday meals and feasting events, then compares it to the results found at the nearby site of Kiskiak to make inferences about the social practices of Shelly’s residents. I analyzed characteristics of oyster morphology such as height, length, height-to-length ratio, left valve concavity, presence/absence/type of epibionts, and presence/absence/type of attachment scar to determine what type of environment the oysters were harvested from. Additionally, I analyzed the presence/absence/type of processing performed on the oysters by the people at Shelly to prepare the oysters for eating to interpret social practices. This analysis shows that shell from both the Middle Woodland midden and the Late Woodland pits display characteristics consistent with subtidal or more saline oyster reefs. At the Kiskiak site intertidal oysters were harvested for daily meals and subtidal oysters were harvested for feasts. Differences in the practices associated with oyster harvesting, consumption, and deposition between the two sites could be due to Kiskiak’s status as a place of political importance and the residence of a werowance (i.e., petty chief), whereas Shelly had no such status.Geolog
Northern Neck Regional Shallow Draft Channel Dredging Plan: Feasibility Phase
No full textThe Initial Phase of the project (Phase 1), used remote sensing and other data collection to develop a method for determining which waterbodies on the Northern Neck of Virginia need dredging. The analysis included most of the waterbodies in the counties of Lancaster, Northumberland, Richmond, and Westmoreland. From this analysis, 19 waterbodies emerged as potentially needing dredged based on physical parameters and residential and economic usage (Milligan et al., 2023). In this Feasibility Phase (Phase 2), more detailed site data were collected to provide data to the localities for consideration. These tasks were included in the analysis: 1. Historic shore evolution. 2. Bathymetric data were collected in the waterbody; 3. Sediment sampling of the upper 1-2 ft of the bottom was performed to determine surface sediment type; 4. Structures adjacent to the channel were assessed; 5. Channels were determined based on whether they were federal, non-federal, or non-federal with aids to navigation (ATONs). Eight federal channels were included in this Feasibility Phase, and the federally-defined channel was used for those waterbodies. However, two waterbodies, Cranes Creek and Monroe Bay, have a federal channel only at their mouth. For this Feasibility Phase, the channel was extended farther into the waterbodies. For non-federal channels, the bathymetric data was used to determine where the natural channel occurred and using aids to navigation (ATONs) where available. 6. Channel volume was calculated based on the maintenance depth plus 1 ft of overdepth. This determines the size of the project and how much area will be needed for disposal of material. 7. The potential disposal location (upland vs. shoreline) was determined for each channel based on sediment type. For shoreline placement, potential adjacent sites are shown. The goal of these data collections and analysis is to provide information to the localities regarding the waterbodies that may need to be dredged to maintain residential and economic usage. It can be used to prioritize dredge channel funding as it becomes available for design and construction. This is a scoping level analysis and should be used for planning purposes only. The parameters chosen for analysis such as proposed channel location and channel depth can be modified during the final design process to fit the needs of the community and to fit available costs. Additional data is needed for final dredge project design in Phase 3. The most crucial data are subbottom cores that are used to determine if the surficial sediments taken for this analysis represent the overall type of material that will be dredged. If the cores reveal sediment different from the surficial analysis, then the placement options may change.Virginia Institute of Marine Scienc
Beyond Form and Content: Using Jewish Ethical Responses to #MeToo as a Resource for Methodology
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Design of an Apparatus for Strain Tuning of Materials.
No full textThe objective of this study is to design and construct an in-situ strain tuning apparatus that is suitable for spectroscopy and resistivity measurements of strongly-correlated materials. The developed apparatus utilizes a piezoelectric actuator and a strain gauge-wheatstone bridge system to apply and measure strain on material samples. The design takes into consideration the mechanical requirements necessary to apply strain to a sample as well as the geometrical constraints of the infrared microscope setup used for spectroscopic measurements. The piezoelectric actuator is used to apply a controlled amount of strain to the material sample. The strain is measured using a strain gauge-wheatstone bridge system that detects changes in the strain gauges resistance caused by the deformation of the sample. This information is measured and allows experimenters to adjust the strain applied in real-time. The strain gauge-wheatstone bridge system is capable of measuring small changes in strain with high accuracy, which is necessary for the precise control of the applied strain. The design of the apparatus also takes into account the geometrical constraints of the infrared microscope setup used for spectroscopic measurements. The apparatus is designed to conform to the dimensions of the existing infrared spectroscopy setup, allowing for easy integration into existing experiments. The sample is positioned in the center of the infrared microscope’s field of view, allowing for the simultaneous measurement of both the optical and electronic properties of the sample under strain. The position of the apparatus is also adjustable, which allows for calibration of the optical alignment of the sample.PhysicsBachelors of Science (BS