Cedar Bayou and Vinson Slough Hydraulic Restoration Non-construction Elements

Summary

Expected Outcomes

1. Restore Cedar Bayou to its historical, open conditions and create a channel between Cedar Bayou and Vinson Slough as a route for migrating marine species. Opening the tidal inlet and allowing a free flow of water between the Gulf and the Aransas-Mesquite-San Antonio bay system has potentially far-reaching regional benefits to the estuary as a whole, as it will revive a bay system that has been denied, by unnatural means, access to life-giving Gulf waters. Cedar Bayou is a relatively undisturbed natural tidal pass accessible only by boat and is distant from any major population centers. Healthy wetland vegetation along the pass shoreline is an excellent but underutilized habitat structure for important commercial and recreational fish species. If reopened, Cedar Bayou will once again provide a rich, year-round source of food for sport fish, wildlife, and invertebrate-eating birds.

2. Increase the hydrologic flow between the Gulf and Aransas-Mesquite-San Antonio Bay System through Cedar Bayou and Vinson Slough. The Coast & Harbor Engineering analysis estimates that the flow rate will increase 250% over the conditions existing when the pass was last functionally open in 2005. A stable increased flow rate should be observable and measured after the first year of post-project monitoring data.

3. Re-introduce tidal flow into Vinson Slough. Vinson Slough will once again connect with Aransas Bay, which will enhance the productivity and diversity of its wetlands and tidal flats.

4. Restore habitat through beach nourishment over approximately 90.4 acres of shoreline on San Jose Island. This beneficial use of dredge material will restore nesting habitat for several endangered species on this uninhabited island, including the piping plover. According to the Texas Shoreline Change Project, about 17 miles of San Jose Island is critically eroding at rates that range from 6.4 to 3.2 feet a year.

5. Increase densities of recruiting juvenile fishes (red drum, flounder) and crustaceans (blue crab and penaeid shrimp) by providing access to nursery habitats of Mesquite Bay. Scientists monitoring the productivity of the bays see virtually no blue crab larvae or first settling juveniles in the area of Cedar Bayou and Mesquite Bay. The project leaders will consider the project successful if post-construction surveys show improvement in densities of juvenile fishes and crustaceans of at least 25% of the populations listed in the Simmons and Hoese study within the first year following opening of the inlet.

Long-term Habitat Benefits

Waters of the U.S restored: 88.6 acres (59.8 acres Vinson Slough & 28.8 acres Cedar Bayou).
Enhanced wetlands in the immediate vicinity: 9,948 acres (8695.9 acres Estuarine Wetlands & 1252.1 acres Palustrine Wetlands).

Tidal flats enhanced: Approximately 4,589.9 acres.

Hydrology restored: ~8,359 acres to Mesquite Bay; ~2,459 acres to Ayers Bay; ~4,659 acres to Carlos Bay; ~7,895 Ac to the southeastern portion of San Antonio Bay; and ~9,004 acres to portions of Aransas Bay.

Restoring the hydrology will restore fisheries corridors to all of the key habitat types: estuarine wetlands, oyster reefs, tidal flats and seagrass habitats.