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The US Army Corps of Engineers (USACE)'s Engineering With Nature® (EWN®) initiative consistently promotes the use of collaboration for identifying innovative, nature-based solutions (NBS) that lead to more resilient communities and water-based infrastructure. In recent years, EWN researchers, in partnership with landscape architects (LAs) affiliated with the Dredge Research Collaborative (DRC), have championed an innovative, collaborative strategy that offers traditional planners an opportunity to participate in visioning exercises during the initial phases of coastal storm risk management projects. This has resulted in the identification, development, and incorporation of design concepts that prioritize NBS and the placement of natural and nature-based features (NNBF). These concepts, and their development process, have been documented in reports for the use of both the participating planners and other audiences interested in innovative NNBF. Upon observing these favorable outcomes, it has become clear that the integration of disciplines-landscape architecture, applied science, and engineering-has increased our ability to process, utilize, and communicate complex information. Both groups (i.e., DRC's LAs and EWN engineers and scientists) have considerable experience related to infrastructure design and performance; they elucidate ways to achieve functional engineering criteria while also maximizing ecological value and/or promoting more recreational opportunities. However, this partnership also produces a complementary set of uniquely acquired skills and expertise, which advances the development of NBS through accelerated and more meaningful communications. This study will offer insight into the partnership, collaborative techniques, and resulting products that have fostered innovation as well as advocacy for more sustainable infrastructure. Integr Environ Assess Manag 2021;00:1-7. © 2021 SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

The US Army Corps of Engineers (USACE) manages hundreds of reservoirs and thousands of miles of navigation channels that provide invaluable flood control, commercial transport of materials, water supply, recreation, and stream flow regulation. This capability is being threatened by the continued occurrence of large-scale wildfires across the western United States. The wildfires damage watersheds in part by denuding landscapes, reducing infiltration rates, and increasing runoff rates, thereby dramatically increasing the potential for the erosion of denuded slopes, destabilizing stream channels, increasing the infilling potential of reservoirs and, hence, reducing their capacity. The increased erosion rates highlight the need to develop innovative solutions to reduce erosion of watersheds laid bare after wildfires engulf the area. The Santa Clara Pueblo in northern New Mexico extends from the top of the eastern Jemez Mountains to the floodplains of the Rio Grande River. The Pueblo designed and constructed thousands of structures built from natural materials, consistent with Engineering With Nature (EWN) principles for erosion control incorporating low-cost and readily available materials such as logs, mulch, vegetation, and local rock to stabilize highly erodible parts of the watershed. The watersheds where these natural structures were constructed were monitored after construction to assess their effectiveness, guiding a series of recommendations for broader implementation. As part of a continued emphasis on updating USACE engineering guidance, research, and development, funding has been focused on developing sustainable and resilient project designs using natural materials like those implemented by the Santa Clara Pueblo. This paper focuses on the innovative EWN-based watershed stabilization practices that were implemented in the upper section of this wildfire affected canyon and tributary streams. Recommendations for future implementation based on lessons learned from this project are also provided. Integr Environ Assess Manag 2021;17:1194-1202. Published 2021. This article is a US Government work and is in the public domain in the USA.

Damaging storm events frequently impact the Texas coast. In response, the US Army Corps of Engineers Galveston District (SWG) has undertaken the Sabine-to-Galveston (S2G) Coastal Storm Risk Management (CSRM) Project. This approximately $3.9B project includes numerous measures across several counties of the upper Texas coast, including levees, floodwalls, and pump stations. In June 2019, SWG leadership enlisted a team including the paper authors to integrate Engineering With Nature (EWN) strategies into this infrastructure project. EWN strategies intentionally align natural and engineering processes to efficiently and sustainably deliver economic, environmental, and social benefits through collaboration. The first step in this process was to develop potentially relevant EWN strategies. A collaborative workshop included visits to project sites and working sessions where the project team reviewed challenges associated with each site, generated an array of EWN strategies, and began to test design concepts based on those strategies through collaborative drawing sessions. Afterward, prioritized ideas were refined and evaluated in terms of property acquisition, estimated cost, logistics, stakeholder and sponsor interest, constructability, aesthetics, recreational opportunities, and ecological benefit. Design concepts considered feasible for integration into the broader S2G project included horizontal levees, inland floodwater storage areas that double as wildlife habitat, and strategic placement of sediment berms to reduce storm impacts and provide marsh substrate. All these concepts should achieve intended CSRM outcomes while enhancing environmental and social benefits. This assimilation of EWN strategies and landscape architecture techniques into a large CSRM study illustrates a method for expanding overall project value and producing infrastructure that benefits coastal communities. Integr Environ Assess Manag 2022;18:63-73. © 2021 SETAC.

The US Army Corps of Engineers (USACE) operates and maintains numerous projects in support of its various civil works missions including flood damage risk reduction, navigation, and ecosystem restoration. Originally authorized on an economic basis, these projects may produce a broad array of unaccounted for ecosystem services (ESs) that contribute to overall human, societal, and environmental well-being. Efforts are underway to capture the full array of environmental, economic, and social impacts of these projects. Methods are needed to identify relevant ESs generated by these nature-based projects and to measure their contribution to societal well-being with an emphasis placed on use of readily available data. Performance metrics were collected to capture the benefits of strategic placement of dredged material in river systems to allow formation of islands that produce a wide array of ESs. These performance metrics can be converted to ESs with market value or combined in a decision analytical approach to demonstrate the relative gain in utility. This approach is demonstrated on a riverine island created on the Atchafalaya River, Louisiana, as a result of the strategic placement of dredged material. The outcomes foster integration of ES assessment into project design and management practices and support more comprehensive project evaluation and widespread application. Integr Environ Assess Manag 2018;14:759-768. Published 2018. This article is a US Government work and is in the public domain in the USA.

Navigation infrastructure such as channels, jetties, river training structures, and lock-and-dam facilities are primary components of a safe and efficient water transportation system. Planning for such infrastructure has until recently involved efforts to minimize impacts on the environment through a standardized environmental assessment process. More recently, consistent with environmental sustainability concepts, planners have begun to consider how such projects can also be constructed with environmental enhancements. This study examined the existing institutional conditions within the US Army Corps of Engineers and cooperating federal agencies relative to incorporating environmental enhancements into navigation infrastructure projects. The study sought to (1) investigate institutional attitudes towards the environmental enhancement of navigation infrastructure (EENI) concept, (2) identify potential impediments to implementation and solutions to such impediments, (3) identify existing navigation projects designed with the express intent of enhancing environmental benefit in addition to the primary project purpose, (4) identify innovative ideas for increasing environmental benefits for navigation projects, (5) identify needs for additional technical information or research, and (6) identify laws, regulations, and policies that both support and hinder such design features. The principal investigation tool was an Internet-based survey with 53 questions. The survey captured a wide range of perspectives on the EENI concept including ideas, concerns, research needs, and relevant laws and policies. Study recommendations included further promotion of the concept of EENI to planners and designers, documentation of existing projects, initiation of pilot studies on some of the innovative ideas provided through the survey, and development of national goals and interagency agreements to facilitate implementation.

During the last four years, significant effort has been devoted to understanding the effects that Hurricanes Katrina and Rita had on contaminant distribution and redistribution in New Orleans, Louisiana, USA, and the surrounding Gulf Coast area. Elevated concentrations were found for inorganic contaminants (including As, Fe, Pb, and V), several organic pollutants (polycyclic aromatic hydrocarbons, pesticides, and volatiles) and high concentration of bioaerosols, particularly Aeromonas and Vibrio. Data from different research groups confirm that some contaminant concentrations are elevated, that existing concentrations are similar to historical data, and that contaminants such as Pb and As may pose human health risks. Two data sets have been compiled in this article to serve as the foundation for preliminary risk assessments within greater New Orleans. Research from the present study suggests that children in highly contaminated areas of New Orleans may experience Pb exposure from soil ranging from 1.37 microg/d to 102 microg/d. These data are critical in the evaluation of children's health.

Sediments collected at various field locations may have chemical and physical constituents that influence test results and may contain organisms that cannot be readily removed. Thus, reference sediments are needed that can be formulated to match diverse freshwater and estuarine sediments encountered in comprehensive testing programs. This research evaluated formulated reference sediments in terms of (a) their ability to match field-collected sediments both chemically and physically; (b) their suitability as habitant (survival and reproduction) for typical invertebrate toxicity testing species (Hyalella azteca Saussure, Chironomus tentans Fabricius, and Daphnia magna Straus) during chronic exposures; and (c) their suitability as a substrate for Hyalella azteca, Chironomus tentans, Daphnia magna, Ceriodaphnia dubia Richard, and Pimephales promelas Rafinesque in 14-d whole-sediment exposures. Formulated reference sediments were prepared to match naturally occurring sediments with respect to particle-size distribution, organic matter, organic carbon, pH, solids, CEC, but not redox potential. After preparation, a conditioning period of at least 7 d was required for pH stabilization of formulated reference sediments. In culture experiments, formulated reference sediments was suitable for Hyalella azteca, Chironomus tentans, and Daphnia magna survival and reproduction for 56,40, and 28 d, respectively. Hyalella azteca, Chironomus tentans, Daphnia magna, Ceriodaphnia dubia and Pimephales promelas survival more » was [>=] 88% in 14-d exposures to formulated reference sediment. Formulated reference sediments may reduce some unexplained physical, chemical, or biological toxicity'' of field-collected sediments (e.g., organic matter) that may influence toxicity testing results. « less

The spread of nonindigenous (nonnative) species introduced into the United States is a significant and growing national problem and results in lost agricultural productivity, increased health problems, native species extinctions, and expensive prevention and eradication efforts. Thousands of nonindigenous species have either become established or spread, and introduction of aquatic nuisance species (ANS) into freshwater lakes threaten aquatic biodiversity. Expanding global trade is likely to increase the number of species that are spread across the globe, so the need to develop an approach to predict potential ANS invasions is great. Risk assessments currently being used to assess ANS risk rely on qualitative or semiquantitative information and expert opinion; thus, such approaches lack transparency and repeatability. A more quantitative approach is needed to augment the qualitative approaches currently in use. A quantitative approach with the use of the traditional ecological risk assessment (traditional ERA) framework combined with decision analysis tools was developed for assessing ANS risks in which the causative ecological risk agent is an organism rather than a chemical. This paper presents a systematic risk assessment framework that includes structured decision analysis to help organize and analyze pertinent data, state assumptions, address uncertainties in estimating the probability of an undesired ANS introduction, or spread and integrate these outputs with stakeholder values. This paper also describes when and how decision analysis tools can be used in such assessments for ANS. This framework and methodology will enable risk managers to systematically evaluate and compare alternatives and actions supporting ANS risk management and thus credibly prioritize resources.

When evaluating the risk chemicals may pose to mammals and birds in ecological risk assessments (ERAs), it is common practice to conservatively assume that all (100%) of a chemical in an environmental medium is bioavailable to receptors. This assumption often leads to overestimating ecological risk and may ultimately result in costly and unnecessary risk management actions. While effects of bioavailability and speciation of metals such as arsenic (As) and lead (Pb) have been considered in human health risk assessment, these effects are rarely taken into consideration when assessing risks to mammals and birds. An ERA was conducted at the former Col-Tex refinery site in Colorado City, Texas, USA, to characterize risks to select wildlife species from exposure to chromium (Cr) and Pb found in soils. The focus on these metals was based on results of a screening-level ERA that found that Cr and Pb were posing ecological risks at the site. Soils were analyzed for total Cr and Pb, trivalent Cr (CrIII), h...

The effects of five di-ortho polychlorinated biphenyl (PCB) congeners on survival, growth, and reproduction in the fathead minnow. Pimephales promelas, were determined. Fish were exposed to one of two nominal concentrations of each congener for a total of 13 weeks (7-week prespawning period plus 6-week spawning period) under flow-through conditions using methanol as a carrier solvent. At termination, P. promelas survival was high in all PCB congener treatments. PCB congeners had no significant sublethal effects on reproductive success within the concentration range examined. The total number of eggs, clutch size, number of clutches, percent hatchability, and presence of terata in offspring were not significantly affected. Reproductive success was slightly but not significantly enhanced in the solvent control and high treatment concentrations for congeners 52, 101, 138, and 153. Growth expressed as wet weight was not affected for both adult males or females. Male lengths were not significantly affected but female lengths were significantly reduced when exposed to congeners 101, 138, 153, and 180. Pimephales promelas accumulated substantial amounts of all PCBs, with tissue concentrations ranging from 13 to 183 mg/kg wet weight at termination in PCB-exposed fish. These tissue residues are one to several orders of magnitude greater than thosemore » reported for these congeners in aquatic biota previously collected in industrial waterways of the Great Lakes. Several di-ortho PCB congeners frequently found in aquatic biota showed minimal adverse effects on fathead minnow survival, growth, and reproduction even though bioaccumulation of these congeners was substantial.« less

The equilibrium partitioning approach for developing numerical sediment-quality criteria was tested in the laboratory using a mixture of chlorinated ethers/alcohols sorbed to sediments. The sorption behavior of the principal component of the mixture, tetrachloropropyl ether (TCPE), was determined on sediments with organic carbon contents ranging from 0.3 to 5.2%. Sorption was found to be a strong function of organic carbon with a log(Koc) of 2.9. Predictions of log(Koc) using Kow correlations and molecular connectivity indexes ranged from 2.9 to 3.3. Toxicity tests were then conducted on sediments spiked with the chlorinated ether mixture using the amphipod Hyalella azteca, the midge Chironomus tentans, and the water flea Daphnia magna. Sediment toxicity was highly dependent on the sediment organic carbon content, but there were differences in toxicity that could not be explained by differences in organic carbon. Interstitial water concentrations of total chloroether did not compare with effects between different sediments for either of the two sediment-dwelling organisms, with LC50 values ranging from 1.6 to 10.5 mg dissolved chloroether per liter for Hyalella azteca and 1.5 to 9.3 mg dissolved chloroether per liter for Chironomus tentans. The effect of other sediment properties on the sensitivity of these two organisms may account for this difference. For Daphnia magna, there was a much closer correlation between interstitial water concentrations and effects, with the aqueous LC50 having a range of only 0.9 to 2.0 mg/L.

To examine equilibrium-partitioning model predictions of interstitial water concentrations of fluoranthene as part of the equilibrium-partitioning (EqP) approach to sediment quality criteria development, the bioavailability (toxicity) of fluoranthene-amended sediment (a nonpolar organic compound) to Hyalella azteca, Daphnia magna, and Chironomus tentans was determined. Fluoranthene was added to three freshwater sediments with similar organic carbon content (0.44-0.50%). Although sediments were from divergent sources (Water Research Field Station [WRFS], Trinity River [TR], and Lake Fork [LF]), sediment physical and chemical characteristics did not vary appreciably, leading us to hypothesize (based on EqP theory) that fluoranthene-amended sediment toxicity would not vary between sediments. Predicted interstitial water concentrations from the equilibrium-partitioning model were similar to measured interstitial water concentrations for WRFS and TR sediment, but the model underpredicted measured values for LF sediment by a factor of two. EC50s for Daphnia magna, Hyalella azteca, and Chironomus tentans in interstitial water were a factor of two to five greater for LF than for WRFS and TR sediments. Factors other than organic carbon content of sediments (e.g., dissolved organic carbon content in interstitial water) probably contributed to the variability in bioavailability of fluoranthene. Based on 10-d sediment toxicity tests with Hyalella azteca, Daphnia magna, and Chironomus tentans, organic carbon-normalized sediment concentrations were better predictors of toxicity than interstitial water and bulk sediment fluoranthene concentrations. In 10-d aqueous-phase tests with fluoranthene, Chironomus tentans and Hyalella azteca were twice as sensitive as Daphnia magna. The response of freshwater organisms to fluoranthene-amended sediment was similar to that of marine organisms exposed to fluoranthene in other studies. The EqP approach for sediment-quality criteria accurately predicted sediment toxicity for WRFS and TR sediments but not for LF sediment, indicating the model may be overly protective for some bottom sediments. Factors other than organic carbon content may be important in affecting neutral organic compound bioavailability.

Sediment characteristics of samples from physiographic provinces of the continental United States were examined to determine variability within and among physiographic provinces and to compare characteristics of freshwater and saltwater sediments. Organic carbon, particle size distribution, particle surface area, cation exchange capacity, redox potential, and percent solids were examined for a variety of lotic and lentic freshwater sediment samples and nearshore estuarine and marine samples from the continental United States. Analysis of variance indicated significant differences (p < 0.05) within and among physiographic provinces for both freshwater and saltwater sediment samples. Sediment characteristics within physiographic provinces were as variable as characteristics among provinces. Freshwater sediment characteristics were not significantly different (p < 0.05) from saltwater sediment characteristics. Saltwater sediment characteristics were observed to be more strongly correlated with each other than were freshwater sediment characteristics. Based on the variability of sediment samples examined in this study, a specific site may require 50 or more replicate samples to be adequately or accurately represented.

Many years of untreated effluent discharge from residential areas, a shipyard, a marina, and a large fish market resulted in substantial contamination of bottom sediment in Southern Busan Harbor, South Korea. Contaminants in these sediments include heavy metals and organic compounds. Newly introduced regulations for ocean disposal of dredged material in South Korea pose significant challenges, because the previous practice of offshore disposal of contaminated dredged material was no longer possible after August 2008. The South Korean government has mandated that such sediments be assessed in a way that identifies the most appropriate dredged material management alternative, addressing environmental, social, and cost objectives. An approach using multicriteria decision analysis (MCDA) in combination with comparative risk assessment was used as a systematic and transparent framework for prioritizing several dredged sediment management alternatives. We illustrate how MCDA can recognize the multiple goals of contaminated sediment management. Values used in weighting decision criteria were derived from surveys of stakeholders who were sediment management professionals, business owners, or government decision makers. The results of the analysis showed that land reclamation was the preferred alternative among cement-lock, sediment washing, 3 contained aquatic disposal alternatives (one in combination with a hopper dredge), geotextile tubes, solidification, and land reclamation after solidification treatment. Land reclamation was the preferred alternative, which performed well across all MCDA objectives, because of the availability of a near-shore confined disposal facility within a reasonable distance from the dredging area. Integr Environ Assess Manag 2010; 6:61–71. © 2009 SETAC