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Tred Avon Recreational User Input Request

The Corps is seeking input until Oct. 15, 2014, from recreational boat users of the Tred Avon River. Oyster reef habitat construction in the Tred Avon River is expected to begin this winter. Construction of oyster reefs at select sites in the Tred Avon River may reduce water depths by at most 1 foot. We are seeking information specifically related to the draft needed for passage of the user’s vessel in the Tred Avon River and the location of docks and moorings and the pathways to access these docks and moorings for potential near-shore construction sites. For more info: Tred Avon River User Input Flyer


Harris Creek Environmental Assessment

Previously, National Environmental Policy Act (NEPA) documentation evaluated the impacts of oyster reef restoration at water depths that maintain at least an 8-foot water column above restored reefs, including many proposed sites in Harris Creek. The Corps prepared a supplemental Environmental Assessment evaluating the impacts of expanding oyster restoration and rehabilitation activities into water depths between six and nine feet. This would maintain at least a 5-foot water column above restored reefs within the Harris Creek oyster sanctuary. The supplemental Environmental Assessment determined there would be no significant environmental impact as a result of this proposed action. Comment period closed April 21, 2014.


Oyster populations in the Chesapeake Bay have declined dramatically since the turn of the century, largely due to parasitic diseases, overharvesting, declining water quality, and a loss of habitat. Less than one percent of historic oyster populations remain. Oyster restoration is important because oysters are filter feeders and help keep the water clean; in addition, oyster bars (or reefs) provide habitat for animals, including blue crabs and fish.

The Native Oyster Restoration Master Plan is the Corps' plan for large-scale, sanctuary-based oyster restoration throughout the Chesapeake Bay and its tributaries. The master plan examines and evaluates the problems and opportunities related to oyster restoration, and formulates plans for implementing large-scale, Bay-wide restoration.

Project elements include: (1) disease-free spat (oyster seeds) from state-owned hatcheries; (2) creation of new oyster habitat; (3) rehabilitation of existing non-productive oyster habitat; (4) construction of seed bars for production and collection of spat; (5) planting spat on the new and rehabilitated bars; and (6) monitoring of project performance. The non-Federal sponsor for the Maryland portion is the Maryland Department of Natural Resources (MDNR).

Locations for restoring oyster reef habitat are selected based on bottom survey data, salinity of water, oyster sanctuary boundaries, general planning guidance from U.S. Coast Guard, and other factors. Typically, there are two barges used for constructing the reef: one barge holds the substrate, the other holds a crane with a bucket to move the substrate.  The bucket picks up the substrate from the barge, then, with a sweeping motion, releases it into the water.  GPS locaters are used to make sure the reefs are constructed in the selected sites. Oyster seed, which are technically referred to as spat on shell, are brought from hatcheries and placed or “planted” on the constructed reefs in hopes of restoring the oyster population in these areas.  Once planted, the oyster reefs will be monitored to assess the restoration progress.

The Maryland project cooperation agreement was executed Feb. 27, 1997, with an amendment in July 2002.  The Virginia project cooperation agreement was executed September 17, 2001, with amendments in July 2004 and June 2007. Placement locations in Maryland include Kedges Strait, Eastern Bay; and the Chester, Choptank, Magothy, Patuxent, and Severn rivers. Some of the oyster bars were left for natural recruitment; others received hatchery-raised spat. Starting in 2001, the program was opened up to the Commonwealth of Virginia; the Corps Norfolk and Baltimore districts support activities in Virginia and Maryland, respectively.  In Virginia, activities include oyster bar creation in Tangier Sound, Pocomoke Sound, the Great Wicomico River, and the Lynnhaven River - a total of approximately 400 acres. Approximately 500 acres of new Maryland oyster bars have been created in the Magothy, Severn, Choptank, Patuxent, and Chester rivers, as well as Kedges Strait and Eastern Bay.

The Maryland Interagency Workgroup consisting of representatives from the Corps, National Oceanic and Atmospheric Administration (NOAA), and MDNR facilitate oyster restoration by coordinating efforts among the state and federal agencies, in consultation with the scientific, academic and oyster restoration communities. The workgroup uses the Corps Native Oyster Restoration Master Plan and the Maryland Oyster Restoration and Aquaculture Development Plan, along with other resoureces. The Tred Avon was selected as the next tributary for restoration, and construction is expected to begin winter 2014.

Prior to the 2009 restoration activities, the Corps oyster restoration program did not focus on large-scale tributary restoration in Maryland, as it does now.  From 1997 to 2006, the Baltimore District received relatively small funding allocations for a number of small sites, scattered throughout the Maryland portion of the Chesapeake Bay.  An assessment of the sanctuary sites constructed during this period was prepared and can be found in the September 2011 report, 2008 Sanctuary Assessment.

Larval Transport Model

Additional Information

Authorization: Section 704(b) of the Water Resources Development Act of 1986, as amended.

Type of Project: Aquatic Ecosystem Restoration

Contribution to the Chesapeake Bay: Directly contributes to Executive Order 13508 goals to restore clean water, recover habitat, and sustain fish and wildlife.

Project Phase: Construction

Non-Federal Sponsor: Maryland Department of National Resources, Virginia Marine Resources Commission

Congressional Interest:  Senators Mikulski and Cardin (MD), Warner and Kaine (VA); Representatives Harris (MD-01), Sarbanes (MD-03), Hoyer (MD-05), Wittman (VA-01), Rigell (VA-02), and Scott (VA-03).


The FY 2013 Maryland contract was awarded in September 2013.  For this contract, clamshell and granite will be placed as substrate on 23 acres in Harris Creek, a tributary to the Choptank River.  The work will be accomplished from December 2013 through February 2014.  Monitoring of the Virginia sites has shown that many of the Great Wicomico and Lynnhaven River sanctuary oyster reefs are exceeding the accepted target for successful oyster restoration. 



Total Estimated Cost (MD+VA)


Federal Cost Estimate


Non-Federal Cost Estimate 


Federal Funds Data  
Allocation thru FY 2012


Allocation for FY 2013 


President Budget FY 20142


Allocation for FY 20142


Balance to Complete


1 Estimate based on the current federal authorization for this program. The long-term master plan has identified a need of $2-6 billion.

2 The President typically sends the budget to Congress in February each year. Upon release, budget amounts for the USACE Civil Works programs and specified projects are posted online at the USACE website in a program budget press book at http://www.usace.army.mil/Missions/CivilWorks/Budget.apsx

3 The final FY 2014 allocation of funds to projects will be available upon enactment of the Energy and Water Appropriations Act or the public release of an approved FY 2014 work plan given continuing authority for the full year.  The FY 2014 funds will be split between Baltimore District and Norfolk District.


FY 2013 Completed Work:  With the funding received, a $1.8M contract was awarded in September 2013 to Argo Systems, LLC, for substrate construction in Harris Creek.  In Virginia, efforts were focused on the completion of a fossil shell survey, continuation of ERDC harvest management modeling efforts, and initiation of development of a Bay-wide NEPA document.  Project monitoring continued at all sites.


FY 2014 Scheduled Work:  

Previous year carry-in funds in the amount of $5,150,000 ($3,150,000 in Baltimore District and $2,000,000 in Norfolk District) are being used for design and construction of the next Tred Avon-Harris Creek substrate contract ($3,150,000), adaptive management of reefs constructed in the Great Wicomico River ($1,500,000), development of a tributary plan for the Lafayette River ($200,000), and complete the tributary plan for the Piankatank River ($300,000).  With the anticipated FY 2014 allocations based on the President’s budget, we will continue program coordination and monitoring ($200,000), add additional acreage to design and construction of the Tred Avon-Harris Creek substrate contract ($4,500,000) allowing for completion of the Harris Creek reef construction, and prepare the next Maryland tributary plan ($300,000).


COMPLETION:  TBD.  With optimal funding and an increase in WRDA cost authority, oyster restoration activities would continue towards achieving the oyster restoration outcome established by the Chesapeake Bay Protection and Restoration Executive Order (E.O. 13508) to restore native oyster habitat and populations in 20 tributaries by 2025.  Without these, it is estimated that by FY16 funds would be used for orderly suspension of the program.

Point of Contact

Baltimore District Public Affairs