EWN Research and Development
The EWN is a cross-cutting initiative with relevant projects occurring through various federally sponsored programs and other government agencies. Some of the current EWN related projects include the following:
DOER Research and Development
The Dredging Operations and Environmental Research Program (DOER) is a federal program under the U.S. Army Corps of Engineers (USACE). DOER supports the USACE Operation and Maintenance Navigation Program. Research is designed to balance operational and environmental initiatives and to meet complex economic, engineering, and environmental challenges of dredging and disposal in support of the navigation mission. Visit the DOER website.
Evaluation of Strategic and Direct Placement to Feed Mudflats and Marshes
POC: Joe Gailani
Understanding sediment processes after placement of fine grained dredged material on or near mudflats and marshes is key to successful application of these methods for rebuilding valuable habitat and flood protection value provided by these resources. Data are limited on application of dredged FGS to protect and nourish mudflats and marshes. If properly applied, dredged material can provide these benefits with minimal interruption to existing habitat. The lack of data demonstrating the benefits of fine grained dredged material for supporting mudflats and marshes has limited appropriate design and regulatory approval of these projects. Design of new projects presently includes large uncertainties resulting in part from the limited monitoring and analysis of previous projects. Comprehensive data sets from selected ongoing projects for the fate of dredged FGS at direct and strategic placement sites implemented to feed mudflats and marshes will support stakeholder outreach and the regulatory approval processes required to obtain project approval and will improve the design/success of these projects.
Quantification of DM Layer Thickness over Time as Applied in TLP Wetland Nourishment Projects
POC: Susan Bailey
This research task includes bench scale testing and field data collection to improve our understanding of dredged material consolidation behavior after thin layer placement. The RT will result in a better understanding of the physical processes involved in placement, dewatering and settlement of dredged material in wetland environments, examining the effects of vegetation on placement density, and plant transpiration and rooting on consolidation and its dynamics. It will provide more robust application of the PSDDF model to calculate dredged material settlement over time in order to optimize attainment of the design elevation(s) to facilitate maintenance of sustainable wetlands via thin layer placement of dredged material. These improvements will allow USACE planners and other agencies involved in ecosystem restoration to better design wetland creation projects to reach target elevations, resulting in fewer projects that fail as a result of missed target elevations.
Predicting marsh response to dredged material placement
POC: Candice Piercy
Advancing the practice of thin layer placement activities in marshes requires a simple tool that can predict how marsh elevation will respond to the sediment placement so impacts can be better quantified and placement activities can be better designed. The planned updates to MEM will incorporate best current science to provide thin layer placement practitioners a tool to better plan and design marsh thin layer placement projects.
Guidance for Wetland Thin Layer Placement (TLP) of Fine and Course Grained Sediment
POC: Candice Piercy and Tim Welp
The guidance document provided by this research task will improve the planning, permitting, design, construction, and maintenance of TLP projects to facilitate the acceptance and expansion of TLP in using dredged material from navigation projects beneficially to restore degraded wetlands.
Sediment Profile Imaging to Evaluate Dredged Sediment Placement
POC: Joe Gailani
Thin-layer placement of dredged sediment in shallow water can support USACE regional sediment management goals. Sediment can be placed stragically in open water, permitting natural hydrodynamic forces to winnow and transport various sediment grain size classes such that desired sediment classes move toward targeted resources, such as wetlands, mudflats, or beaches. These sediments will then nourish the resources and address sustainability issues related to recession, subsidence, and sea level rise. However, shallow water placement sites often include critical benthic habitat. Therefore, regulatory approval may be difficult to obtain and, once permitted, significant restrictions may be applied to minimize risk to benthic habitat. SPI monitoring systems, placed strategically around a placement site during and after operations can be used to desmonstrate that regulatory criteria are being met. The monitoring systems can also be used to adaptively manage placement operations and assure regulatory compliance. Post-placement, SPI systems will quantify the rate of benthic habitat recovery. Application at multiple sites will permit development of guidance documents to improve thin-lyaer placement approval and management at additional sites.
EMRRP Research & Development
The Ecosystem Management and Restoration Research Program (EMRRP) is a federal program under the USACE. EMRRP is the USACEs tactical research and development response to the demand for new and expanding technologies to address the need for ecosystem assessment, restoration, and management activities at the project level. Visit the EMRRP website.
Evaluating Ecological Success of Beneficial Use on Deer Island
POC: Safra Altman
Beneficial use (BU) restoration projects have potential to provide marsh habitat and substantial ecological function to systems, but quantifying these benefits are important for planning and project justification. To gain a better quantitative understanding of marsh restoration following BU site development, Engineer Research and Development Center Environmental Laboratory (ERDC-EL) researchers are studying Deer Island.
Restoring and Sustaining Ecological Function in Coastal Marshes Affected by Sea Level Rise
POC: Elizabeth Murray
Loss of coastal marsh areas critical for their ecological and storm protection functions has become a national concern. Loss can be attributed to sediment starvation, sea level rise, and other local factors. Currently, little guidance exists pertaining to the sustainable restoration and management of impacted marsh areas. This Ecosystem Management and Restoration Research Program (EMRRP) research unit focuses on developing an empirically supported framework delineating the ecological and environmental considerations relevant to restoration of salt marshes for the purpose of offsetting effects of sea level rise.