The Georgia Bight: The Southeast's Great Coastal Curve

The Georgia Bight (also called the South Atlantic Bight) is a broad, shallow, concave embayment of the Atlantic Ocean stretching from Cape Fear, North Carolina to Cape Canaveral, Florida—encompassing the entire coasts of South Carolina and Georgia.

Key Characteristics

• Width: ~200 miles (320 km) at widest.
• Inland Reach: ~100 miles (160 km) from shelf break to coast.
• Depth: Average ~50 ft (15 m); gently sloping continental shelf.
• Tides: Semi-diurnal, high range (6–10 ft) — funnels water into estuaries.
• Sediment: Quartz sand from Appalachians via rivers (Savannah, Altamaha, Ogeechee, Santee, Pee Dee).

Ecological Significance

• Salt Marshes: ~400,000 acres — 1/3 of US East Coast total; nursery for shrimp, blue crab, fish.
• Estuaries: Altamaha, Savannah, ACE Basin — high biodiversity, critical habitat.
• Barrier Islands: Sea Islands (Hilton Head, Tybee, St. Simons, Jekyll, Cumberland) — protect mainland, host dunes, maritime forest.
• Fisheries: Shrimp (white, brown), oysters, crabs, red drum, flounder, offshore snapper/grouper.

Geologic Origin & Future

Formed by post-glacial sea-level rise (~18,000–6,000 ya) flooding river valleys. The bight is subsiding; sea level rising ~1 inch (2.5 cm)/year — accelerating. This threatens marshes, infrastructure, and freshwater aquifers (saltwater intrusion).

Human Stakes

Ports: Savannah (#4 US container), Charleston, Jacksonville, Brunswick. Tourism, military bases (Kings Bay, Mayport, Parris Island), nuclear plants (Vogtle, Hatch). The bight is an economic engine and ecological treasure—both at risk.