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The Mississippi / Atchafalaya River Basin is the nation’s largest drainage area, directing over 1.2 million square miles of runoff from America’s heartland to the mouth of the delta and transporting fertile sediment downstream.
Image credit: Dredge Research Collaborative

The Mississippi’s levees, spillways, and revetments trap sediment in the main course of the river, impeding navigation and port activity and starving adjacent floodplains and wetlands of this nourishing resource. This image shows active dredging operations in the Birds Foot Delta in southern Louisiana. 
Photo credit: Ben Mendelsohn and Alex Chohlas-Wood

Lake Michigan is edged with a thick network of federally maintained navigation channels serving commercial and recreational interests, requiring periodic dredging and sediment relocation.   
Drawing credit: Dredge Research Collaborative

Currently, more than half of the material annually dredged in the Great Lakes requires placement in nearshore landfills, or Confined Disposal Facilities (CDFs). Many of these facilities are at capacity and unable to accommodate projected future needs.
Photo credit: Sean Burkholder
Drawing credit: Dredge Research Collaborative

The Placement and Reuse Facility (PRF) at Erie Pier in Duluth, Minnesota highlights a potential future for dredged sediment. Rather than a site of long-term disposal, the facility separates dredged sediment into graded material that can be resold and reused locally.
Photo credit: Brett Milligan

Dredging in the Bay and Delta enables ship traffic, generates material for shoreline construction, and remediates contaminated grounds. Where channels cut through the Delta, salinity intrusion into the waterways will follow, with cascading effects on already stressed aquatic habitats.
Drawing credit: Dredge Research Collaborative

An average of 3-6 million cubic yards of sediments are dredged from the San Francisco Bay every year to maintain safe navigation, 40% of this material is beneficially reused. While multiple restoration sites exist around the bay that need sediment for survival, financial and logistical hurdles often prevent beneficial reuse and lead sediment to be disposed of offshore, exported from the system.
Drawing credit: Dredge Research Collaborative

The 2,600 acre Hamilton Wetlands restoration site received millions of cubic yards of dredge piped from the Port of Oakland’s Harbor Deepening project onto the flat expanse of a retired airfield. This project was realized through careful timing and planning –advance notice of the harbor deepening project allowed for the sediment ‘matchmaking’ to occur, while economies of scale made the movement of sediment financially feasible.
Photo credit: Dredge Research Collaborative

Dredge Research Collaborative (DRC)
2017 – $10,000 Silt, Sand & Slurry: Sedimentary Infrastructure and the Geography of Dredge” Book Publication Project

The Dredge Research Collaborative (DRC) is an independent 501c3 nonprofit organization which investigates human sediment handling practices, through publications, events, and design projects. Our mission is to improve sediment management through design research, building public knowledge, and facilitating transdisciplinary conversation. Over the past ten years, the DRC has been at the forefront of exploring the massive human impact on the flows and movements of sediments, and investigating how these flows might be more intelligently and equitably designed.

The members and co-founders of the DRC organized the critically acclaimed DredgeFest event series across the four coasts of the United States. The first DredgeFest was held in New York City on September 28 and 29, 2012. DredgeFest NYC was organized in partnership with Studio-X NYC, an arm of Columbia University’s Graduate School of Architecture, Planning, and Preservation; sponsored by Arcadis, TenCate, and TWFM Ferry; and featured speakers and content from agencies including the US Army Corps of Engineers, National Park Service, Environmental Protection Agency, and New York City Economic Development Corporation. The second DredgeFest was held in Louisiana from January 11 to 17, 2014. Partners included the Robert Reich School of Landscape Architecture at Louisiana State University, the Coastal Sustainability Studio at Louisiana State University, the Center for Land Use Interpretation, Gulf Coast Public Lab. The third DredgeFest was held in Minnesota from August 14 to 21, 2015. DredgeFest Great Lakes was hosted by the University of Minnesota’s School of Architecture and Department of Landscape Architecture. DredgeFest California, the fourth event, included five days of interdisciplinary design workshops, discussions with many different experts, two days in the field with the DredgeFest California public tours, and background research conducted prior to the event. It was supported by Great Lakes Dredge and Dock, Landscape Architecture Magazine, the UC Davis Hellman Fellows Program, the University of California, Davis’ Department of Human Ecology, Groundworks Office, the Delta Protection Commission, the University of California, Berkeley’s Department of Landscape Architecture and Environmental Planning, and the Dutra Museum Foundation.

Each DredgeFest was designed as a learning encounter between government agencies, designers, theorists, academics, corporate practitioners, industry experts, students, and the public. Each DredgeFest situated sedimentary management in the context of current regional conversations and issues, including climate change, sea-level rise, wetland restoration, environmental justice, public access and recreation

In terms of design and landscape architecture, members of the DRC actively serve as consultants to multiple state and Federal agencies and NGOs to collaborate on infrastructural and ecological restoration design projects, including working with The US Army Corps of Engineers, U.S. Army Engineer Research and Development Center, US Fish and Wildlife Service, CA fish and Wildlife Service and the Nature Conservancy. Members of the DRC also co led the Public Sediment Team and helped craft their award-winning proposal for the Resilient by Design Bay Area Competition.

In addition to publishing numerous articles, book chapters and planning reports, they will soon be publishing a book called Silt Sand Slurry: Dredging, Sediment, and the Landscapes We Are Making, authors Rob Holmes, Brett Milligan and Gena Wirth demonstrate why sediment matters now more than ever, given sea level rise, accelerated environmental change, and spatial inequity. This is approached through a documentation of the geography of dredging and sediment on the four coasts of the continental United States. This documentation is accomplished through alternating, complementary visual chapters and text chapters. Along the way, they explore the many limitations of the way that sediment systems are currently designed, such as short-sighted efforts to keep dynamic ecosystems from changing, failure to value sediment as a resource, and inequitable decision-making processes. Finally, using Public Sediment as a case study, they describe an approach to designing with sediment that is adaptive, healthy, and equitable.