By Michele S. Byers
Street flooding is not unusual in New Jersey’s coastal towns, especially during high tides, heavy rains, on-shore winds and full moons.
But coastal residents are noticing more frequent flooding than in past years. In some places, sea and bay waters spill over the roads at high tide, even on clear days with little wind.
New research shows the sea level is rising at faster-than-anticipated speeds. This is due to both sea level rise and land slowly sinking (an occurrence known as subsidence).
New Jersey hasn’t always been the same peanut-shaped land mass. Throughout the Earth’s history, sea level has fluctuated and the location of the coastline in this state we’re in has shifted. New Jersey would have been unrecognizable.
About 145 million years ago, the Atlantic coast ran from Perth Amboy to Trenton. Sixty-five million years ago a shallow sea covered southern New Jersey, from roughly Asbury Park to Salem. That’s why sand, shells and fossilized aquatic creatures can be found far inland from today’s coast. When you hike in the Pine Barrens, you are walking on the ocean floor of only a few million years past.
Much more recently – 20,000 years ago – a great ice sheet extended as far south as northern New Jersey. Because much of Earth’s water was frozen in glaciers, the Atlantic coastline was located about 75 miles east its current location out in the sea. As the ice sheets melted, sea level began rising again.
Around 3,000 years ago, according to the Rutgers Institute of Marine and Coastal Sciences, sea level stabilized near its current level. During the years 1 through 1800 AD, sea level in New Jersey rose only 6 inches per century.
But things are speeding up. Measurements taken at bedrock locations in Bayonne, Trenton and Camden show that sea level in New Jersey rose by 12 inches in the 20th century, double the previous rate. And at the Jersey shore, sea level rose 16 inches.
According to Rutgers scientists, it’s likely that New Jersey’s coastal areas will experience sea level rise between 12 and 22 inches by 2050. Under a worst-case scenario, these communities could see the sea level rise as much as 2.8 feet by 2050.
According to the Union of Concerned Scientists, over the next 30 years – the lifetime of a typical home mortgage – more than 62,000 residential properties will experience chronic flooding two times a month or more. Coastal cities, particularly those on our barrier islands, will be most affected, but residences along inland waterways will also experience regular flooding.
Several organizations are working to find ways for New Jerseyans to prepare for this change. The Regional Plan Association released its Fourth Regional plan which recommends that officials in the tri-state area accelerate efforts to adapt to a changing climate by moving development away from vulnerable coastal areas.
“Today, more than a million people and 650,000 jobs are at risk from flooding, along with critical infrastructure such as power plants, rail yards, and water treatment facilities,” according to the plan. “By 2050, nearly two million people and one million jobs would be threatened.”
The Fourth Regional Plan also recommends a tri-state regional coastal planning commission.
State Assemblyman Reed Gusicora (now the mayor of Trenton) introduced a bill in March that would establish a 19-member New Jersey Coastal Commission to plan for major projects and decisions related to shore protection in Atlantic, Cape May, Middlesex, Monmouth and Ocean counties.
The coastal commission concept was first proposed by former Gov. Thomas Kean decades ago, without success. But with the inevitability of sea level rise it’s a good time to revisit this concept. Gusicora’s bill is now before the Assembly Environment and Solid Waste Committee.
Michele S. Byers is the executive director of the New Jersey Conservation Foundation, Far Hills. She may be reached at firstname.lastname@example.org