Long Island Beach Erosion
Coastal communities along Long Island are in a battle against nature.
![](https://cdn.arcgis.com/sharing/rest/content/items/0788b5f6e3154caba3c5902230024acb/resources/1564672886176.jpeg?w=20)
A lot of people long to live near the beach, wake up to the tides, lounge in the sun; living that life comes at a price many do not suspect. Residents of Montauk know of this cost all too well. For them, they have dealt with a diminishing shoreline for the last 2 decades. Records show that the shoreline has moved 44 feet inland at the rate of a little more than 2 feet a year. https://www.newsday.com/long-island/environment/long-island-erosion-beaches-1.34297563
Long Island is a barrier island with a year round population of 50,000. Long Island New York is the largest island adjoining the contiguous United States, extending approximately 118 miles east-northeast from the mouth of the Hudson River Totaling 1,377 square miles of land area, Long Island New York is divided into four counties: Kings (Brooklyn), Queens, Nassau, and Suffolk. Suffolk is the easternmost and by far the largest of the four, covering an expanse of 911 square miles. Following Suffolk is Nassau with 287 square miles, Queens County with 109, and Kings with 70 square miles, the westernmost County. Kings and Queens Counties (Brooklyn and Queens) border each other and fall within the jurisdiction of New York City.
In recent years the shores have been hit by several storms that have caused serious flooding and erosion in many communities. Erosion threatens to damage public and private property and structures with an estimated value upward of $10 billion dollars, as well as displacing residents and businesses in these areas.
Erosion is the process by which large storms, flooding, strong wave action, sea level rise, and human activities wear away beaches and bluffs along coastlines. Sea level rise will cause an increase in coastal erosion and the human response will be critical. https://toolkit.climate.gov/topics/coastal-flood-risk/coastal-erosion
The video below briefly shows the geological history of Long Island:
Several events have contributed to the shape the island is in today. Earthquakes as well as storms and hurricanes all have impacted the island and the land nearby. In the 1980s 3 earthquakes shook Long Island. Since 2000, 2 tropical storms, 1 superstorm and 6 other hurricanes have impacted this area. With each event more damage to the beaches occurred. https://projects.newsday.com/databases/long-island/storms/
![](https://cdn.arcgis.com/sharing/rest/content/items/0788b5f6e3154caba3c5902230024acb/resources/1564684806712.jpeg?w=20)
Long Island Town Scrambles To Fight Beach Erosion
Hazards of Beach Erosion
- damages to structures
- loss of roads
- flooding (resulting in potential loss of life)
- displacement of businesses and residents
- loss of money for the area (tourism)
On November 26, 2012 the U.S. Geological Survey released before and after images showing the devastating impact that Hurricane Sandy had on coastal dunes along the Fire Island National Seashore in Long Island, NY. The images show widespread dune erosion and over wash. In some areas, coastal dunes lost as much as 5 meters (15 feet) in elevation. A USGS scientist said the coastline had suffered 30 years of change, from this one storm. https://earthsky.org/earth/sandy-caused-30-years-of-change-to-ny-coastline-study-shows
Natural Processess
Coastal lands and sediments are constantly in motion. Breaking waves move sand along the coast, eroding sand in one area and depositing it on an adjacent beach. Tidal cycles bring sand onto the beach and carry it back into the surf. Rivers carry sediment to the coast and build deltas into the open water. Storms cause deep erosion in one area and leave thick overwash deposits in another. Plants retain sediment in wetlands and impede movement of coastal dunes. Natural processes that change the water level also affect coastal dynamics. Taken individually, each natural process of coastal transport is complex; taken collectively, they create an extraordinarily intricate system that attempts to achieve a dynamic balance.
Waves, Tides, and Weather
Winds create waves that ripple across the surface of lakes and seas until they break on the shallowing bottom and crash into the shore. In many areas, prevailing winds produce waves that consistently approach the coast at oblique angles. Even the slightest angle between the land and the waves will create currents that transport sediment along the shore. These longshore currents are a primary agent of coastal movement; they are a major cause of sand migration along barrier and mainland beaches.
Tides ebb and flood in response to the gravitational attraction of the moon and sun; exceptional high and low tides occur each month when the sun and moon are aligned. Tides help determine where the waves break -- low on the beach at low tide, high on the beach at high tide -- and, therefore, where sand is deposited and removed. Rip tides, or undertow, occur along most beaches and can move significant amounts of sand offshore.
Damage from Superstorm Sandy
Storm systems along coasts contain high winds, create large waves, and cause storm surges that raise water levels as much as 7 meters above normal. Although storms are sporadic, they are the primary cause of beach erosion along many coasts. Storms carry sand seaward, forming offshore bars; much of this sand migrates landward during calm weather. Some areas are more storm prone than others. Storms often are concentrated in specific seasons; along the eastern seaboard, for example, hurricanes occur in the late summer and early fall, and storms are especially frequent during the winter months. These seasonal trends result in a general difference between the winter "eroding" beach and the summer "building" beach that is most common along parts of the west coast.
What Happens Next?
As of July 2018, the Army Corps of Engineers was set to continue work on the $50 million second phase of its federally funded coastal protection project on the beach — the replenishment of sand and dune construction — with sand pumping that was scheduled to begin that same month. Since pile-driving was expected to take about a month, the corps sought to secure a noise variance grant to work 24 hours a day.
Project Update: Long Beach, NY
In April 2019, the U.S. Army Corps of Engineers announced the official completion of construction on the Long Beach Coastal Storm Risk Reduction Project.
The $130 million project was performed in two phases over three years that included construction of four new groins and the rehabilitation of 18 existing ones, as well as installing 284,000 tons of rock. The Corps also used 3.2 million cubic yards of sand to widen the beach and reinforce sand dunes, which play a crucial role in flood risk reduction. The Corps was also able to expand the beach approximately 150 feet from Long Beach to Point Lookout. The work stretched for nine miles along the coast of the Barrier Island, from Jones Inlet to East Rockaway Inlet. The project was completely funded by the federal government.
https://patch.com/new-york/longbeach/army-corps-says-long-beach-restoration-project-completed