Its depth ranges from shallow waters in the southern extension, called Peck Bay, to a 33 ft (10 m) deep channel.

During the Sangamonian interglacial period, the Great Egg Harbor River existed as a delta that covered much of southern Cape May County.

In the eastern periphery, the bay measures 5.0 mi (8 km) along the coast, bordered by Ocean City on the east.

During the Sangamonian interglacial period, melting glaciers formed rivers that carried sediment to the coast of the Atlantic Ocean.

The formative Great Egg Harbor River existed as a delta at that time, covering much of what is now Cape May County.

[4] In 1614, Dutch explorer Cornelius Jacobsen May discovered the bay, surrounded by plentiful birds laying eggs.

[8] In 1880, one year after Ocean City was established as a Christian resort, regular steamboat service from Somers Point began.

[13] In 1928, a bridge in northern Ocean City opened, crossing Great Egg Harbor Inlet to marshlands in Atlantic County.

[2] At the inlet, the shifting currents produce a hazardous waterway to boats, due to changes in the channel related to shoaling.

[21] To improve navigation and replenish beaches in Ocean City, the United States Army Corps of Engineers has periodically dredged sand from a location 5,000 ft (1,500 m) offshore the Great Egg Harbor Inlet.

In 2018, Act Engineers Inc. began a $2.75 million project to install 1,450 ft (440 m) of concrete blocks, which would provide shelter for oysters and restore the island's marshes.

[20][8] The waterway and its channels carrying silt produce a soft bottom, creating a good habitat for shellfish that covers a 706 acres (286 ha) area.

[26] By the 18th century, Somers Point had several shipyards along the Great Egg Harbor Bay, supporting the shipbuilding industry.

[20] The barrier islands to the north and south – Ocean City and Longport – are heavily developed, with bulkheads modifying the natural coastline.