Coastal Flooding in Rhode Island: History, Causes, and Future Projections

King tide flooding occurs when the Sun, Earth, and Moon align, enhancing gravitational pull on oceans, affecting coasts.

The Rising Waters: An In-Depth Look at Coastal Flooding in Rhode Island

Coastal flooding is a growing concern in Rhode Island as natural phenomena like king tides and storm surges increasingly threaten low-lying areas. These events offer a preview of the future challenges posed by climate change and rising sea levels. Understanding the causes and impacts of these floods can help communities better prepare for the inevitable changes.

Tidal Flooding

King tide flooding, Newport

King tides occur when the gravitational forces of the Sun and Moon align, creating higher than normal tides. These tides can flood coastlines, affecting beaches, docks, and roadways. The situation becomes more severe if a storm system coincides with a king tide, resulting in amplified flooding due to storm surge and rainfall. For more on king tide flooding, visit this link.

Storm Surge

Storm surges occur when tropical storms, hurricanes, or Nor’easters force seawater onto land, causing coastal flooding. When combined with high tides, these surges result in storm tides, which have historically led to significant flooding in Rhode Island. Structures like the Fox Point Hurricane Barrier have been built to mitigate such risks.

Sea Level Rise

The warming atmosphere, largely driven by climate change, accelerates the melting of glaciers and polar ice sheets, contributing to rising sea levels. Greenland alone has lost an estimated 587 cubic kilometers of ice from 1900 to 2001, equivalent to filling 235 million Olympic-size swimming pools. Additionally, the thermal expansion of seawater, as it absorbs heat, increases ocean volumes. The tide gauges in Newport and Providence have documented a significant rise in sea levels, with Newport recording an 11.64-inch increase and Providence a 10.32-inch increase since record-keeping began in the early 20th century.

Historical Coastal Floods

Rhode Island’s coastline has a history of severe flooding events. Here are some of the most significant:

August 1635 – The Great Colonial Hurricane

This hurricane produced a storm surge of 14’-20’ in Narragansett Bay, causing significant flooding, although detailed records are scarce due to the era.

September 1815 – The Great September Gale

The storm surge reached 18 feet in Providence, completely inundating downtown and causing severe damage to Bristol’s waterfront.

September 1938 – The Great New England Hurricane

Known for its destruction, this hurricane submerged portions of downtown Providence under 20 feet of water, dramatically altering local geography.

August 1954 – Hurricane Carol

Following a similar path as the 1938 hurricane, Hurricane Carol caused catastrophic flooding in Providence, leading to the construction of the Fox Point Hurricane Barrier.

August 1991 – Hurricane Bob

The last hurricane to make landfall in Rhode Island, Hurricane Bob, caused a storm tide 10.4 feet above flood stage in Providence.

April 2007 – Patriot’s Day Coastal Storm

This late-season storm caused moderate flooding and significant damage to Newport’s water infrastructure.

October 2012 – Superstorm Sandy

Despite making landfall in New Jersey, Sandy caused a storm surge of 3’-5’ along Rhode Island’s south coast, with damage described as equivalent to a Category-1 hurricane.