Initial construction of the levee
An aerial view of Atkinson Marsh
[July2005]
The San Jacinto Monument
from Atkinson Marsh
Overview
In Upper Galveston Bay, the Port of Houston Authority and the U.S. Army Corps of Engineers constructed levees with clay materials from the Ship Channel Deepening to create more than 800 acres of marsh at Atkinson Island. The first four cells (NW, M1/2, M3, and M4) in the BUG Plan for the Atkinson Island Marsh were constructed in 2001.
2001-2004
The New Work (NW) cell was filled in the spring of 2002 with material dredged from the expansion of the Mid-Bay section of the Houston-Galveston Navigation Channels Project. Once a cell is filled, it takes approximately two years for the water to drain out of the dredged material and the material to settle to inter-tidal level. When the material reaches inter-tidal level, and creeks and ponds have naturally formed or will be constructed, vegetation is then planted on the “new” wetland cell.
2005-2007
The Atkinson Marsh Cells received minimal damages from 2005’s Hurricane Rita and the marsh itself remained undamaged.
The NW cell reached its target elevation and was seeded using a hovercraft in February 2005. The seeded vegetation sprouted and formed excellent inter-tidal marsh coverage by 2007. A breach was excavated in the NW Cell Levee to allow for open inter-tidal exchange, which includes ingress and egress of marine organisms in 2007 as well. The ratio of open water to vegetation, elevation, and circulation remained excellent for the new work cell.
The remaining existing cells (M1/M2, M3, and M4) remained open water lagoons and were filled in 2007 and seeded via hovercraft in the spring of 2008. As the vegetation continued to establish itself and natural circulation patterns continued to emerge, it was evident that these three cells would also achieve excellent ratios of open water to marsh.
2008-present
Marsh surveys conducted in the early Summer of 2009 show that the marsh has settled to the lower end of the inter-tidal range and has an excellent marsh to open water ratio. The BUG continues to monitor the progress of these cells through regular site visits and surveys. The BUG is currently developing a plan to open sections of the levees to allow additional circulation for tides and marine life.
The M5/6 Cell, a 340-acre marsh cell, was constructed in 2008 and will be filled over several cycles. It received its first cycle of maintenance material in January 2009. It is expected that it will be filled to its target elevation in 2011/2012.
Once again, 2008’s Hurricane Ike damaged Atkinson Marsh Cells only minimally however, the levees and shore protection received minor damages. Repairs to the levees and shore protection is expected to occur in the Spring of 2010. Additionally, breaches will be constructed on the interior levees to allow for better circulation between the cells. Additional breaches of the exterior levees are still in the planning and design phases.
Utilizing American Restoration and Recovery Act (ARRA) funding, the Port of Houston and the United States Army Corps of Engineers are continuing marsh creation efforts in Upper Bay. The levees for marsh Cells 7, 8, and 9 will be constructed adjacent to the M5/6 Cell behind Upland Placement Area 15 to create 380 acres of intertidal marsh. Additionally, the levees for Marsh Cell 10 will be constructed behind and connected to Placement Area 14 to create approximately 350 acres of inter-tidal marsh. Breaches will be left in the levees to allow for circulation and the cells will remain open water lagoons until they are filled. The new marsh cells are expected to be filled over many maintenance dredging cycles (approximately every other year).
The open water area between Placement Area 14 and 15 has been identified by the USACE Engineer Research and Development Center as a conduit for sediment transport and shoaling in the Houston Ship Channel. In an effort to reduce the shoaling of the navigation channel and to create additional placement capacity for dredged materials, Placement Areas 14 and 15 will be connected and the area between the cells will be used for upland placement of dredged materials. Construction of the ARRA Project will commence in the Spring of 2010 and is expected to be completed by the fall of 2011.
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Overview
