A partnership has been instituted through the Gulf of Mexico Alliance (GOMA) among the Gulf States to enhance the ecological and economic health of the Gulf of Mexico. Established under the GOMA, the Habitat Conservation and Restoration Team (HCRT) recognized that sediments are integral to and a critical resource in accomplishing the GOMA conservation and restoration objectives. As a result, the Gulf Regional Sediment Management Master Plan (GRSMMP) was initiated for managing sediment resources and corroborates the need for an understanding of regional sediment processes. The plan provides guidelines using the understanding of sediment dynamics to manage resources toward accomplishing environmental restoration, conservation, and preservation while enhancing abilities to make informed, management decisions. A key step in this process is the recognition of a technical framework that provides a foundation associated with regional sediment management processes essential for establishing management guidelines that balance sediment dynamics and available sediment resources with needs and that enhance abilities to make informed management decisions and develop regional strategies. Issues surrounding sediment management, both natural and dredged sediments, have a considerable impact on the ability to sustain coastal habitats. Sediment management must occur on a regional scale unencumbered by agency, state, or political boundaries. Guidelines and recommendations from this effort will aid the Gulf States in more effective management of sediment resources, recognizing they are a part of a regional system involving natural and man-made processes. The effort involves a range of state and federal agencies, as well as nongovernmental representatives. Thus, a technical framework for the GRSMMP was compiled/completed and submitted to the HCRT/GOMA. The decision was made to publish this document as peer-reviewed papers in a special issue of the Journal of Coastal Research for benefit of the global scientific community. In return, feedback in terms of review and comments will be beneficial for the team.

This contribution is part of the Gulf Regional Sediment Management Master Plan and serves as a broad overview of the general setting, geologic history, coastal processes, hydrodynamics, and sediment sources for the Gulf of Mexico (GOM). The GOM is approximately 1,500,000 km². The five U.S. states bordering the Gulf comprise over 75,000 km of coastline. Gulf circulation is dominated by the Loop Current and gyres. The general trend of longshore sediment transport is in the westward direction west of the Mississippi River and in the eastward direction east of the Mississippi River, and is driven primarily by the wave and tidal energy. The GOM is a shallow basin and its climate is strongly dependent on precipitation and temperature averages. The general coastal climate is subtropical with warm to hot summers and cool winters with precipitation and high relative humidity throughout the year. The GOM coast is predominantly microtidal (<2-m range) with coastal processes and associated morphodynamics strongly influenced by storms. Tropical cyclones have affected every GOM coastal county or parish since 1900. Over 150 rivers flow into the Gulf; 85% of the fluvial water contribution is from U.S. rivers and of that, 64% is from the Mississippi River, which discharges approximately 2.4 billion kg of sediment annually. Humans are altering the natural coastal sediment budget through beach nourishment and dredging that affects the beach–dune sediment exchange. Six of the 10 most socioeconomically vulnerable coastal counties in the United States are in the Gulf region, which emphasizes the need for a sediment management master plan.

Development of dynamic regional sediment management (RSM) plans is needed for future planning, construction, and monitoring of wetland and barrier island restoration. Broadly speaking, RSM refers to the optimum use of various sediment resources (littoral, estuarine, and riverine) in an environmentally effective and economically feasible manner. Coordination of the supply and demand sides of sand resources in a comprehensive manner will be required as project planning develops and evolves. The sediment budget is a planning tool that provides an accounting of sediment sources, sinks, and pathways as well as engineering activities and sediment budgets have generally been characterized as conceptual, interim, and operational depending upon the quality of the data, the level of analysis, and the uncertainty associated with the volume fluxes in the sediment budget. This paper summarizes existing sediment budget data for the entire Northern Gulf of Mexico. The purpose of this work has been to compile available sediment budget data into a common geographic information system–based data management framework in order to address various sediment management issues related to restoration around the Gulf of Mexico. The regional sediment budget is comprehensive and current through year end 2008. Within the coastal management community, there is an increasing awareness of the importance of reliable sediment budgets to inform sediment management decisions. However more work is needed to refine the sediment budget and provide its appropriate place in coastal management decisions.

The Gulf of Mexico (GOM) continental shelf, extending approximately 1600 km from the Florida west coast to the U.S.–Mexico border, is a large sedimentary basin that has been the focus of much geologic study and surveys during the past 70 years, related mostly to oil and gas exploration. Relatively little attention has been focused on mapping and assessing offshore sediment character and resources, such as sand. It is increasingly recognized, however, that baseline scientific information on seafloor sediment character and composition is needed for managing and protecting natural resources and for providing information on sand availability and quality for potential use in a variety of coastal restoration and protection projects in all five of the states from Florida to Texas. The geomorphologic character and shallow sedimentary stratigraphy of the GOM shelf has been determined over geologic time by sediment inputs from rivers; sea-level fluctuations up to 120 m, resulting in transgressions and regressions of the shore; and frequent storms. These processes have resulted in deposition, reworking, and preservation of a variety of sand bodies, both on the seafloor and in buried, ancestral stream channels. Sand bodies of highly varying grain size, sorting, color, and composition are present throughout parts of the GOM inner shelf, varying greatly in size and number and often overlain or admixed with finer-grained, muddy sediment. The shelf sand bodies tend to be fine grained and are often mixed with muddy or organic detritus as well as carbonate shell material. The GOM shelf is mantled with sand mostly off the Florida shore, and sediments become progressively finer and muddier westward across the Alabama, Mississippi, Louisiana, and Texas shelf regions. The shelf off each state contains shoals that represent drowned paleoshoreline and buried, ancestral, stream-channel features that originated when sea level was lower than at present and the shore was farther seaward. These shoals offer the best promise as potential sand resources; however, further study is needed to refine these findings based on reconnaissance-scale work.

Dredging activities are a potential source of sediment and should be considered in any conservation and restoration planning process. Wise use of sediment resources from dredging is integral to accomplishing the conservation and restoration initiatives and objectives being recommended under the Gulf of Mexico Alliance. Keeping dredged sediments within the natural system or using it in the construction of restoration projects can improve environmental conditions, provide storm damage protection, and contribute to habitat creation and restoration goals. Hundreds of millions of cubic yards of sediments are dredged each year from Gulf ports, harbors, and waterways, much of which could be used beneficially. Currently it is estimated that about 30% of all material dredged from federal channels in the Gulf states is used beneficially and very little of the privately funded dredging is used for beneficial purposes. The U.S. Army Corps of Engineers (USACE) conducts dredging under its navigation maintenance program and much of the dredging conducted is typically done on a scheduled and routine basis. Successful planning of beneficial-use projects utilizing USACE dredging necessitates the early coordination and work of multidisciplinary interagency teams on a regular basis. There is also a need to improve data access and management for dredging activities for use by project managers and planners.

Water and sediment resource planning is a vital facet of natural resource management. There have been many ecologically disruptive consequences from conventional resource management plans. In the northern Gulf of Mexico (GOM) nearby communities depend on water and sediment resources both ecologically as well as economically. The value of these resources is determined by habitat structure and ongoing sediment dynamics. This article explores how human activities have changed sediment dynamics in relation to the ecology of the habitats present in the northern GOM. It further presents ideas to prevent future problems through sediment management plans that account for natural processes. The northern GOM contains several habitats that are affected by sediment/water resource management plans such as the shoreface (beaches and dunes), barrier islands, hardbottom (coral and oyster reefs), bays, marshes, and forested wetlands. Many common techniques for water/sediment resource management have been used in these areas such as dredging, hard structures (jetties, groins, sea walls, and breakwaters), dams, diversions, levees, and coastal development. The implications of these different management techniques can lead to extensive changes in coastal habitats. Dredging causes disturbances to both borrow and placement sites and can change natural community structure at both sites. The installation of hard structures can cause severe changes in habitat structure that can lead to losses of species diversity. The impacts of river management structures (dams, levees, and diversions) alter the delivery of sediment needed by coastal habitats for growth and sustainability. Anthropogenic development in coastal regions prevents those areas from maturing naturally. Because of the importance of sediments to the ecology of the northern GOM coast and its vulnerability to natural and anthropogenic disturbances, several recommendations are made for holistic future sediment management plans.

Currently, a number of organizations across the Gulf Coast are simultaneously collecting and distributing proprietary data. However, if Gulf Regional Sediment Management Master Plan (GRSMMP) users are to perform analysis efficiently and make effective, educated decisions to support various coastal projects, collaboration and data sharing at all levels of government and among the numerous shareholders must be established. One method of doing this is the implementation of an enterprise geographic information system (EGIS)—a geospatial technology infrastructure that delivers spatial information products, services, and standard data sets to all business elements and processes within and among organizations. The U.S. Army Corps of Engineers has developed and/or participated in a number of such enterprise GIS efforts, including the eCoastal, CE-Dredge, and Spatial Presentation Viewer programs. It is therefore proposed that the GRSMMP establish a firm data management plan and implement an organized, enterprise approach to data management through the use of Web Map Services (WMS). By including the publication of planned data acquisition, inventory of available offline data products, and direct access to organization flagship data sets, such a proposal would allow GRSMMP members to locate, connect to, view, and retrieve desirable data sets across many agencies, saving time and money previously dedicated to new data acquisition.

Eleven habitat restoration case studies were summarized for a variety of habitat types, restoration goals, and project sizes. Each project had unique characteristics that required its own specific approach to habitat restoration/creation, habitat conservation, and beneficial use of sediment required for restoration. However, in every case, the underlying theme associated with restoration or conservation was effective use of sediment. For example, upland disposal of dredged material for bird habitat to avoid adverse impacts of increased turbidity on seagrass beds worked well for Laguna Madre, but Louisiana used similar material for containment dikes and marsh restoration. In both cases sediment was used for habitat restoration rather than disposed of outside the active sediment system. Project success for all case studies depended upon clear and consistent communication among stakeholders. Addressing concerns associated with proposed restoration early in the process builds confidence among stakeholders and a level of trust that often carries through the project approval process.