15 Oct 2024

Deployable Resilient Installation Water Purification and Treatment System (DRIPS): Relief Well Biofouling Treatment of Dams and Levees

Abstract: The US Army Corps of Engineers (USACE) conducts regular inspections and maintenance of relief wells to ensure their proper functionality and to identify early signs of malfunction or potential failure. Expenses associated with labor, materials, and transportation are the primary cost drivers of relief-well maintenance. To minimize labor hours and materials, a treatment approach intended to improve logistics and reduce material costs during relief-well treatment was developed and tested. This approach employed external UVC, mechanical brush treatments, and chlorinated-gas-infused water to produce liquid sodium hypochlorite (NaClO). Preliminary bench-scale testing with chlorine, oxalic acid, and UVC informed the selection of field testing methods and optimal amendment concentrations. Field demonstrations were conducted annually over three years. During the demonstrations, the system underwent continuous optimization to enhance its efficiency. Different locations in Mississippi (Grenada Dam, Eagle Lake, and Magna Vista) were selected for testing. Both new and traditional treatment approaches yielded adequate results, achieving microbial reduction at 96% to 100%. The development and refinement of this system demonstrated that relief wells can be treated within a comparable timeframe and with similar efficiency while utilizing fewer purchased chemicals and materials.

15 Oct 2024

Vegetation Establishment and Management in USACE Floodwater Detention Basins: Greens Bayou Flood Risk Management Mitigation Project

Abstract: This report documents efforts by the US Army Engineer Research and Development Center (ERDC) in assisting the US Army Corps of Engineers (USACE) Galveston District (SWG) in native vegetation establishment design, propagation, installation, monitoring, and adap-tive management for the mitigation requirements of the Greens Bayou Flood Risk Management Project. Specifically, to provide (1) a vegetation establishment design ensuring development of sustainable native plant communities compatible with flooding and drought events; (2) suitable native aquatic, wetland, and woody plants for project use; (3) implementation of plantings; (4) monitoring and adaptive management; and (5) vegetation establishment reports and an operations and maintenance manual for long-term vegetation management of the project site. The Greens Bayou Project included approximately 3.7 miles of channel conveyance improvements and 138 acres of storm-water basin detention storage to reduce flooding damage by safely storing excess stormwater during heavy rain events and slowly releasing it back into the bayou. The completed basin was designed to hold approximately 1,400 acre-ft, or 538 million gal., of stormwater. Vegetation establishment, monitoring, and adaptive management efforts in the mitigation features discussed herein occurred between 2019 and 2023.

30 Sep 2024

A Review of Habitat Modeling Methods That Can Advance Our Ability to Estimate the Ecological Cobenefits of Dredge Material Placement

Abstract: Beneficial use of dredged material (BUDM) has been a placement strategy within the USACE for over 35 years, with applications that aim to reduce navigation costs, increase flood protection, and generate ecological benefits. However, the tools and approaches used for estimating ecological benefits are often limited in comparison with those available to evaluate costs and more traditional economic benefits when moving and placing dredged material. There are statistical and mechanistic models that can aid in quantifying habitat benefits within the context of BUDM projects, but there is currently no USACE-approved process that facilitates the integration of these modeling approaches. The purpose of this document is to provide a comprehensive review of existing habitat-centric statistical and mechanistic models that may aide the USACE in identifying models most appropriate for quantifying potential ecological benefits and trade-offs at placement sites.

27 Sep 2024

Advancements in Riverine Fish Movement Modeling: Bridging Environmental Complexity and Fish Behavior

Abstract: Understanding fish movement and response in relation to their environment near infrastructure and migratory barriers is crucial for developing sustainable fisheries management solutions. Intermediate-scale movement models are a contemporary approach for understanding and predicting movement patterns of riverine fish considering their changing environment, which is predominately water flow. These models can be complex and require interdisciplinary knowledge. For more than 60 years, different approaches have been developed for investigating, reproducing, and predicting the movement outcomes of fish decision making. Due to the breadth of model frameworks available, a systematic review is helpful to summarize the available knowledge including a description of general model properties, environment modeling, agent characteristics, and methods of data use, output, and validation. The analysis of 38 studies found a wide range of model frameworks and architectures. Despite the lack of consistency, each model imposed some combination of the following behaviors: response to flow direction (i.e., rheotaxis), response to flow velocity magnitude, response to turbulence, response to depth, and memory/experience of the individual. There is a clear need for more consistent modeling approaches, increased consideration of memory/experience, inclusion of a wider range of species, incorporation of more detailed environmental covariates, and use of time-dependent solutions in fish movement models.

27 Sep 2024

Habitat and Landcover Classification and Maritime Forest Restoration Recommendations for Deer Island, Mississippi

Abstract: This report addresses two objectives: (1) an island-wide survey and mapping initiative to document habitat and landcover types present on Deer Island, Mississippi, and (2) an evaluation of forested resources on Deer Island along with recommendations to improve and expand the extent of maritime forests on the island. Diverse habitats were documented, including more than 30 distinct habitat and landcover types ranging from wetland marshes to maritime forests and sand ridges. The habitat and landcover survey (and accompanying maps) support ongoing and future ecosystem restoration activities, provides baseline data to conduct change analysis over time, and informs decision-making related to the management of the island’s natural resources. Additionally, the characterization of Deer Island’s forests documented a range of forest health conditions dictated by elevation gradients, soils, invasive species presence, and other factors. Collectively, the data presented inform ongoing planning efforts related to restoration activities on the island as well as future management opportunities to ensure Deer Island continues to provide ecological functions that benefit the community of Biloxi, Mississippi. The results and recommendations herein are broadly applicable to other barrier islands across the northern Gulf region and promotes additional research into the ecology of these unique coastal features.

27 Sep 2024

Potential Engineering With Nature Features to be Incorporated at Woodtick Peninsula

Purpose: Woodtick Peninsula is a barrier peninsula in western Lake Erie where restoration activities are being planned to combat erosion of the peninsula wetlands through placement of dredged material. As part of the restoration effort, design of an artificial reef is currently underway to function as a breakwater, preventing erosion of the fine-grained material being hydraulically placed along the west side of the peninsula. To the extent possible, it is desirable to design the reef such that it would not only provide erosion protection, but also incorporate features that would provide habitat, and thereby support the goals of Engineering With Nature® (EWN®). EWN is a concept focused on aligning natural and engineering processes to deliver economic, environmental, and social benefits efficiently and sustainably through collaboration. A range of breakwater and shoreline armoring alternatives have been utilized in coastal environments to enhance habitat. While a number of alternatives have been successfully demonstrated in marine waters, fewer structures have been adapted to freshwater systems of the Great Lakes. However, there have been several demonstrations within the Great Lakes in which breakwater structures have been enhanced to incorporate habitat features. In this report, potential designs for breakwaters and shoreline edging in freshwater systems that can incorporate EWN benefits are summarized.

27 Sep 2024

Beneficial Use of Dredged Sediment in South St. Paul, Minnesota: 100 Years of Economic, Social, and Environmental Innovation

Purpose: This technical note provides a review of beneficial use (BU) of dredged sediment in a 5-mile river reach of the Upper Mississippi River System (UMRS) that demonstrates the triple-win solutions championed by the US Army Corps of Engineers (USACE) Engineering With Nature® Program. Several case studies exemplifying the BU of dredged sediment are presented along with a more in-depth review of the Pigs Eye Lake Islands ecosystem restoration project.

27 Sep 2024

Surveys in Native and Introduced Ranges (2018–2021) for Natural Enemies of Yellow Floating Heart, Nymphoides peltata Kunth

Abstract: Yellow floating heart (Nymphoides peltata), a widespread aquatic invasive plant in the US, is currently under investigation for biological control de-velopment. From 2018 to 2021, we conducted native (Europe: 14 loca-tions; Asia: 80 locations) and introduced (US: 39 locations) range surveys to create a list of candidate agents and collect baseline infestation data for comparison. We genetically characterized populations and determined those most-closely related to US N. peltata were European. However, we found no promising agents in that region, except for previously reported fungal pathogens. In Asia, several herbivores were identified as potential agents based on observed damage in situ and previous literature reports about host specificity. These included three species of Bagous weevils, one of which may be Bagous charbenensi, and an unidentified leaf-mining Hy-drellia fly. During domestic surveys, generalist leaf-cutting caterpillars were common, similar to the native range. A major discovery was the dam-aging fungal pathogen, Septoria villarsiae, isolated from plants in a pri-vate pond in Maine—the first record in the Western hemisphere. The next steps for this program should include preliminary host specificity and im-pact assessments of S. villarsiae, the fruit-feeding Bagous spp. in China and Korea, and the leaf-mining Hydrellia sp. fly from South Korea.

24 Sep 2024

Validation of Sample Extraction and Analysis Techniques for Simultaneous Determination of Legacy and Insensitive Munitions (IM) Constituents

Abstract: Currently, no standardized method exists for the analysis of insensitive munitions (IM) in environmental matrices such as water, soils, and tis-sues. However, standardized methods, such as United States Environmental Protection Agency (EPA) 8330B, exist for legacy munitions for water and soil matrices. The lack of standardized methods for IM analysis leads researchers to use a wide variety of incomplete and overlapping analytical methodologies. The overall project’s first phase, Strategic Environmental Research and Development Program (SERDP) Environmental Restoration (ER)–2722, was to develop and optimize methods to address these methodological gaps by creating analytical methods for simultaneous analysis of IM and legacy munitions in water, soil, and tissue matrices. The main objective of the current project phase, Environmental Security Technology Certification Program (ESTCP) ER19-5078, is to build upon the previous work in phase one and to focus on the validation of the newly developed methods. Synergizing with the main objective of the overall project, the methods were validated and submitted to the EPA for inclusion as a possible addendum to EPA 8330B.

19 Sep 2024

Case Study of Continental-Scale Hydrologic Modeling’s Ability to Predict Daily Streamflow Percentiles for Regulatory Application

Abstract: Regulatory practitioners use hydroclimatic data to provide context to observations typically collected through field site visits and aerial imagery analysis. In the absence of site-specific data, regulatory practitioners must use proxy hydroclimatic data and models to assess a stream's hydroclimatology. One intent of current-generation continental-scale hydrologic models is to provide such hydrologic context to ungaged watersheds. In this study, the ability of two state-of-the-art, operational, continental-scale hydrologic modeling frameworks, the National Water Model and the Group on Earth Observation Global Water Sustainability (GEOGloWS) European Centre for Medium-Range Weather Forecasts (ECMWF) Streamflow Model, to produce daily streamflow percentiles and categorical estimates of the streamflow normalcy was examined. The modeled stream-flow percentiles were compared to observed daily streamflow percentiles at four United States Geological Survey stream gages. The model's performance was then compared to a baseline assessment methodology, the Antecedent Precipitation Tool. Results indicated that, when compared to baseline assessment techniques, the accuracy of the National Water Model (NWM) or GEOGloWS ECMWF Streamflow Model was greater than the accuracy of the baseline assessment methodology at four stream gage locations. The NWM performed best at three of the four gages. This work highlighted a novel application of current-generation continental-scale hydrologic models.