The U.S. Army Corps of Engineers released a sweeping report Friday on back bay flooding in New Jersey that singles out climate change as a “significant” contributor and says coastal communities face a combined average of nearly $1.6 billion a year in damage in the future if steps aren’t taken.
The report, called the “New Jersey Back Bays Coastal Storm Risk Management Study,” analyzes engineering, economic, social and environmental issues surrounding flooding in the back bays, defined as tidal waterways located landward of the Atlantic Ocean coast in Monmouth, Ocean, Atlantic, Burlington, and Cape May Counties. In all, it’s a 950-square-mile area that includes 3,400 miles of shoreline.
Though attention is often focused on tourist-filled areas facing the ocean, New Jersey’s other shorelines have been a problem spot for flooding. The study was conducted and paid for by the U.S. Army Corps’ Philadelphia office and New Jersey Department of Environmental Protection. It presents preliminary findings on potential plans to manage tidal flooding and storm surge.
“Further vulnerability to coastal storms and the potential for future, more devastating events due to changing sea level and climate change is significant,” the report states. “Rising sea levels represent an inexorable process causing numerous, significant water resource problems.”
The report comes at a time when the Trump administration, according to published reports, is seeking to arrange a panel that would look at whether climate change is even a threat. A Feb. 14 White House memo laid out a plan to create a 12-member committee, which would include Princeton professor William Happer, a longtime critic of the consensus among climate scientists that carbon dioxide emitted by fossil fuels is causing climate change.
Regardless, the Army Corps report includes sections on both climate change and sea level rise. New Jersey is faced with a double whammy: Its land is naturally sinking because of geology and other factors, while the ocean is rising because higher temperatures are melting Arctic ice.
The report includes possible solutions, such as installing storm surge barriers, tide gates, levees, and flood walls. It also makes other suggestions, such as raising homes, restoring marshes, and creating living shorelines, which are made up of native vegetation or other natural alternatives.
For example, the authors found that surge barriers might be viable for Manasquan Inlet, Barnegat Inlet, Absecon Inlet, and Great Egg Harbor Inlet. But they might not be viable at the Little Egg Inlet between Long Beach and Brigantine Islands, or the Hereford Inlet in North Wildwood because the benefits might be limited compared with the costs.
Preliminary results show that flood walls and levees could work in Cape May City, West Cape May, Wildwood Island, West Wildwood Island, Stone Harbor, Avalon, Sea Isle City, Ocean City, Absecon Island, Brigantine Island, Long Beach Island, and just north of Manasquan Inlet.
But flood walls and barriers could have negative environmental consequences on wetlands and could be visually unappealing. The report said a more detailed examination of alternatives will be conducted in the future. No construction would begin until after the final report is due in 2022.
The report says that, based on state data, global sea levels are rising at a rate of 3.5 millimeters a year (less than an inch), but have risen about eight inches since the Industrial Revolution. The East Coast is experiencing higher rates. By 2080, water levels along the New Jersey coast are projected to increase by 1.15 to 4.02 feet.
“It is anticipated that the study area will continue to experience damage from coastal storms, and that the damage may increase as a result of more intense storm events,” the report states, noting that shorelines are changing in response to sea-level rise, and erosion will accelerate.
If nothing is done to address climate change, the report states, the 84 communities included in the back bays study area could collectively see $1.57 billion in average annual damage between 2030 and 2080, based on an intermediate rate of sea level rise. However, threats can be lessened if steps are taken, such as installing barriers and flood walls, but those are potentially costly.
Atlantic City is projected to have the highest average annual damage at nearly $324 million. It’s followed by Ocean City at almost $220 million.