The Puzzle Of White Rocks Island

By John Singleton

In the heat of the summer, it can resemble an icy glacier jutting more than 20 feet above the surface of the Patapsco River. To boaters, the collection of massive boulders one nautical mile northeast of Rock Creek looks more like the craggy coastline of Martha’s Vineyard than the smooth shorn river-landscape of Pasadena.

“There’s always been lots of talk about where these giant rocks came from,” said Greg Pabst, who docks his 36-foot sailboat, “Vesper,” out of the Maryland Yacht Club in Pasadena. “But there’s just not much information around. It’s kind of a mystery,” he added.

Some think they fell off a barge hundreds of years ago. Others imagine them to be a remnant of some distant ice age. One thing is certain: when John Smith sailed the Chesapeake Bay in 1608, those islands of stone were lodged firmly in the navigable channel that Smith chronicled so carefully in his captain’s log. In fact, the Indian name “Patapsco,” (or “pota-psk-ut” in Algonquian dialect) means “white rocks.”  Therefore, both Rock Creek and the Patapsco River owe their names to this puzzling geological formation. Stony Creek, a short distance to the west, is named for a smaller heap of brown rocks at its mouth believed to be of the same geological stratum as those of White Rocks.

“The fishing around White Rocks is particularly lively,” said Pasadena fisherman Jack Streb, who was named Ambassador of the Chesapeake by Governor Martin O’Malley. “Perch fishing is especially good. They like the shade and shelter the rocks provide,” he continued.

As for their frosty color, some experts believe the white pinnacles were formed from an accumulation of oyster shells fossilized in sedimentary rock over thousands of years. Other saltier tales posit they’ve simply been bleached by a millennium of bird droppings. According to the Maryland Department of Natural Resources, the White Rocks Islands, as they are sometimes called, consist of tough, erosion-resistant, white sandstone of the Late Cretaceous period, which accounts for their color. That means this pile of boulders has been around since the dinosaurs were here. Moreover, in the coastal plains region, which includes the Chesapeake Bay, most geology consists of unconsolidated sediment. White Rocks is a notable exception, given its mineral grains have been cemented together to form a tightly packed sandstone.

“To boaters on the Bay and the Patapsco, White Rocks is a landmark,” explained Streb, who added, “In recent years the state has added a channel marker fixed to the rocks, for safety reasons, primarily for commercial ships navigating the river at night.”

At its submerged base, White Rocks covers more than one square acre, and is composed of a dense, white, quartzite, more than 25 feet thick. The bleached cliffs stretch at jagged angles, hinting at the primeval force that once wrenched them apart like an ancient jigsaw puzzle.

Despite its relative anonymity, White Rocks has received its share of attention over the years. Maryland legislative sessions as far back as 1890 document attempts to procure a lighthouse and fog bell to be affixed at White Rocks. Those efforts failed. The White Rocks Marina in Pasadena is also named after these iconic Maryland landmarks.