5 Oct 2023

Beneficial Use of Dredged Material: A Workshop to Explore Engineered Drainage Soils for Stormwater Management

PURPOSE: Beneficial use of dredged material in engineered soils is an alternative to achieve environmental and economic sustainability for waterway operations. Engineered soils can combine navigation and environmental dredging with municipal and commercial waste streams to create a valuable commercial soil product while reducing public operating costs, creating economic opportunity, and creating better soil products for lower cost. The need, opportunities, and challenges to establishing an Illinois Waterway-based commercial soil industry were explored by river, highway, stormwater, environmental resource managers, and industry experts in a workshop in Peoria, IL, on 4–5 September 2019.

29 Sep 2023

A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Wetland Functions of Forested Riverine Wetlands in Alluvial Valleys of the Piedmont Region of the United States

Abstract: The Hydrogeomorphic (HGM) approach is used for developing and applying models for the site-specific assessment of wetland functions. It was initially designed for use in the context of the Clean Water Act Section 404 Regulatory Program permit review process to analyze project alternatives, minimize impacts, assess unavoidable impacts, determine mitigation requirements, and monitor the success of compensatory mitigation. However, a variety of other potential uses have been identified, including the design of wetland restoration projects, projecting ecological outcomes, developing success criteria and performance standards, and adaptive monitoring and management of wetlands. This guidebook provides an overview of the HGM approach including classification and characterization of the principal alluvial riverine wetlands identified in the Piedmont physiography. Eight potential subclasses of Piedmont wetlands, including Headwater, Low- and Mid-gradient Riverine, Floodplain Depression, Footslope Seeps, Flats, Precipitation Depressions, and Fringe wetlands were recognized. However, the occurrence of Flats, Precipitation Depressions, and Fringe wetlands in the Piedmont, are uncommon and not generally associated with alluvial riverine systems which is the subject of this Guidebook. Detailed HGM assessment models and protocols are presented for the five most common Piedmont riverine subclasses: Headwater, Low- and Mid-gradient Riverine, Floodplain Depression, and Footslope Seep. For each wetland subclass, the guidebook presents (a) the rationale used to select the wetland functions considered in the assessment process, (b) the rationale used to select assessment models, and (c) the functional index calibration curves developed from reference wetlands used in the assessment models. The guidebook outlines an assessment protocol for using the model variables and functional indices to assess each wetland subclass. The appendices provide field data collection forms. In addition, an automated spreadsheet model is provided to make calculations.

26 Sep 2023

During Nearshore Event Vegetation Gradation (DUNEVEG): Geospatial Tools for Automating Remote Vegetation Extraction

Abstract: Monitoring and modeling of coastal vegetation and ecosystems are major challenges, especially when considering environmental response to hazards, disturbances, and management activities. Remote sensing applications can provide alternatives and complementary approaches to the often costly and laborious field-based collection methods traditionally used for coastal ecosystem monitoring. New and improved sensors and data analysis techniques have become available, making remote sensing applications attractive for evaluation and potential use in monitoring coastal vegetation properties and ecosystem conditions and changes. This study involves the extraction of vegetation metrics from airborne lidar and hyperspectral imagery (HSI) collected by the US Army Corps of Engineers (USACE) National Coastal Mapping Program (NCMP) to quantify coastal dune vegetation characteristics. A custom geoprocessing toolbox and associated suite of tools were developed to allow inputs of common NCMP lidar and imagery products to help automate the workflow for extracting prioritized dune vegetation metrics in an efficient and repeatable way. This study advances existing coastal ecosystem knowledge and remote sensing techniques by developing new methodologies to classify, quantify, and estimate critical coastal vegetation metrics which will ultimately improve future estimates and predictions of nearshore dynamics and impacts from disturbance events.

26 Sep 2023

Microseira wollei (M. wollei) Blooms in Freshwater Ecosystems in Lake St. Clair (Michigan, USA)–Impacts and Possible Management Approaches

PURPOSE: The proliferation and shoreline accumulation of the filamentous biphasic cyanobacterium, Microseira wollei (M. wollei) (previously classified as Lyngbya wollei), have become an increasing problem in the Great Lakes, both for aesthetic reasons and its potential to harbor harmful bacteria and pathogens (Vijayavel et al. 2013). Occurrences have been reported and studies have also been conducted in the southeastern US where M. wollei has become a nuisance in recent years and is known to produce toxins (Hudon et al. 2014). Reports of M. wollei proliferations in the eastern US have been identified in the Manitoba lakes (Macbeth 2004), in Lake Erie from Maumee Bay (Bridgeman and Penamon 2010), in Lake St. Clair near Detroit (Vijayavel et al. 2013), and throughout the St Lawrence River (Vis et al. 2008; Lévesque et al. 2012). M. wollei has become a serious nuisance for marinas, public beaches, and lakefront property owners. In addition, M. wollei appears to have the ability to produce a wide range of toxins, but the conditions promoting their production, type, and concentration are poorly known (Hudon et al. 2014). Occurrences of large algal mats matching characteristics of M. wollei have been observed along the northwest shore and nearshore waters of the beach at Lake St. Clair dating back to 2010. To date, a comprehensive study detailing the potential impacts M. wollei has on freshwater ecosystems in the Great Lakes River, particularly Lake St. Clair is lacking. Further, management solutions are not well understood. This technical note (TN) reviews the potential causes of M. wollei blooms and their ecological impacts on aquatic systems and assesses the management options available to eliminate or minimize the impacts of these blooms.

26 Sep 2023

Linking the SEDLZJ Portable Standalone Library to the CMS Coastal Hydrodynamic Model

PURPOSE: This document describes the repackaging and linkage of the Sandia National Laboratories Environmental Fluid Dynamics Sediment Processes Code (SNL-EFDC-SEDZLJ), (Thanh et al. 2008). It was originally incorporated within a modified version of the US Environmental Protection Agency’s (USEPA) EFDC public-domain surface-water flow, sediment transport, and water-quality model developed by John Hamrick (Hamrick 1992) and its linkage to the ERDC-CHL-CMS hydrodynamic model. SNL-EFDC simulates flow and transport of sediment as bedload and suspended load. SNL-EFDC-SEDZLJ improves EFDC with updated sediment kinetics subroutines. Sediment erosion is calculated using data collected with a Sediment Erosion at Depth flume (SEDflume). SEDflume measures erosion rates as a function of shear stress and depth from relatively undisturbed cores taken directly from the sediment bed below the water body of interest. The use of SEDflume data provides more accurate sediment erosion rates that are directly input to the model.

25 Sep 2023

Defining Levels of Effort for Ecological Models

BACKGROUND: While models are useful tools for decision-making in environmental management, the question arises about the level of effort required to develop an effective model for a given application. In some cases, it is unclear whether more analysis would lead to choosing a better course of action. This technical note (TN) examines the role of ecological model complexity in ecosystem management. First, model complexity is examined through the lens of risk informed planning. Second, a framework is presented for categorizing five different levels of effort that range from conceptual models to detailed predictive tools. This framework is proposed to enhance communication and provide consistency in ecological modeling applications. Third, the level of effort framework is applied to a set of models in the Middle Rio Grande River system to demonstrate the framework’s utility and application. Ultimately, this TN seeks to guide planners in determining an appropriate level of effort relative to risks associated with uncertainty and resource availability for a given application.

21 Sep 2023

Field Demonstration of a Peroxide-Based Algaecide for Harmful Algal Bloom Control in Lake Okeechobee

Abstract: Large-scale cyanobacterial harmful algal blooms (cHABs) in Lake Okeechobee, Florida, and connected waterways routinely impair water resources. This study conducted a field demonstration of a peroxide-based algaecide in 2020 in the Pahokee Marina on Lake Okeechobee to evaluate the algaecide’s suitability for near-future operational implementation. Within minutes of treatment, rapid oxidation of cHAB cells occurred in the form of bleaching and cell lysis. On average, levels in the treatment area decreased by 4 hours after treatment (HAT) and remained low out to 24 HAT: chlorophyll decreased 87%, phycocyanin decreased 85%, total microcystin levels decreased from 50 μg L⁻¹ to 4 μg L⁻¹ at 4 HAT and then increased to 11 μg L⁻¹ by 24 HAT, hydrogen peroxide concentrations averaged 6.1 mg L⁻¹ 0.5 HAT and then dropped below detection limits by 24 HAT, and Microcystis spp. cell densities decreased at 4 HAT in all but four sampling sites. However, inflows of cHAB-infested lake water in some portions of the treatment area resulted in lack of control at these sites. Because of their vulnerability to influxes of cHABs from surrounding nontreated waters via water-exchange processes driven by wind-induced surface currents, future applications must therefore consider treatment area size.

18 Sep 2023

A Resilient Path Forward for the Marine Transportation System: Recommendations for Response and Recovery Operations from the 2017-2019 Hurricane Seasons

Abstract: The Marine Transportation System (MTS), Resilience Integrated Action Team (RIAT), is tasked by the coordinating board of the US Committee on the MTS to serve as a coordinating body to identify the impacts, best practices, and lessons learned by federal agencies involved in the response and recovery of the MTS after hurricane seasons. In response to this request, the RIAT has focused its analysis on the ability of MTS federal agencies to prepare, respond, recover, and adapt to as well as from disruptions. This was accomplished through workshops focused on gathering the collective experiences of emergency response professionals. In 2017, recommendations were gathered based on experiences responding to Hurricanes Harvey, Irma, and Maria. In this report, a similar approach was adopted to gather findings from Hurricanes Florence and Michael in 2018 and Hurricane Dorian in 2019. Utilizing the successes, challenges, and best practices from all six of these storms, the RIAT identified key coordinating bodies and the participants for each and key takeaways relative to the coordination of agencies with respect to the four steps of resilience: prepare, absorb, recover, and adapt.

18 Sep 2023

Accelerated Corrosion of Infrastructural Seven-Strand Cables via Additively Manufactured Corrosion Flow Cells

Purpose: The purpose of this project was to generate an accelerated corrosion methodology capable of producing seven-strand cables with simulated corrosive defects for calibration of nondestructive analysis (NDA) techniques. An additively manufactured accelerated corrosion cell was motivated and designed. Previous attempts at accelerated electrochemical corrosion used a large cable area with a current density that was too low (i.e., 1 A/m²)* to effectuate efficient corrosion. The accelerated corrosion cell presented here takes advantage of the restricted area within the corrosion flow cell to maximize the corrosion rate in a consistent and calibrated manner (i.e., 2,000 A/m²).

15 Sep 2023

Real-Time Forecasting Model Development Work Plan

Abstract: The objective of the Lowermost Mississippi River Management Program is to move the nation toward more holistic management of the lower reaches of the Mississippi River through the development and use of a science-based decision-making framework. There has been substantial investment in the last decade to develop multidimensional numerical models to evaluate the Lowermost Mississippi River (LMMR) hydrodynamics, sediment transport, and salinity dynamics. The focus of this work plan is to leverage the existing scientific knowledge and models to improve holistic management of the LMMR. Specifically, this work plan proposes the development of a real-time forecasting (RTF) system for water, sediment, and selected nutrients in the LMMR. The RTF system will help inform and guide the decision-making process for operating flood-control and sediment-diversion structures. This work plan describes the primary components of the RTF system and their interactions. The work plan includes descriptions of the existing tools and numerical models that could be leveraged to develop this system together with a brief inventory of existing real-time data that could be used to validate the RTF system. A description of the tasks that would be required to develop and set up the RTF system is included together with an associated timeline.