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| Old Inlet near Pelican Island is where Fire Island was cut in half by the storm |
The storm surge, waves and wind of Hurricane Sandy brought
destruction to the ocean front communities of New Jersey and New York. As a child I spent many
a weekend visiting Neponsit driving from Ditmas Avenue in Brooklyn a straight
shot down Flatbush Avenue to the causeway. Neponsit, the western most part of
the Rockaways, is part of Queens borough- though still part of the same barrier
island (sandbar) that contains Breezy Point. For residents that
think I invaded their strictly private beach, I had cousins that lived in
Neponsit a couple of houses from the ocean. Crossing over to the sand bar
always seemed like entering another world with the beautiful homes and white
beaches, but after Hurricane Donna and the winter storm the following year, I
understood both the magic of the Ocean and its power and danger.
Neponsit is part of the New York estuary. Estuaries occur in
quiet, partly enclosed coastal regions where rivers meet the sea. Estuaries are
the mixing zone where the fresh water and sediments from rivers meets the
seawater and tidal forces. The
ecological balance within the estuary can be very complex, affected by the
volume and rate of fresh water flow from the river, the type and quantity of
sediments in the river, the topography of the coastline, the tidal range, and
the strength and direction of prevailing wind and waves. With all the
variations possible there are actually only four major types of estuaries in
the world: Drowned River Valleys; Tectonic Estuaries; Sand Bar or Barrier
Island Estuaries; and Fjords. New York harbor, New Jersey and Long Island are
barrier Island estuaries.
Barrier islands in the United States occur along the east coast
and the Gulf. Barrier islands were created by the waves depositing sand along
the eastern coast and Gulf when sea level began to rise 18,000 years ago. As
sea level continues to rise, year after year for hundreds of centuries the
seaward side of the barrier island has been eroded away by waves and wind. Sea
level continues to rise (reportedly at an accelerated pace) and waves continue to
erode away the seaward side of the barrier islands while winds carry sand and
silt to be deposited on the landward side in the marshes and harbors. This is a
continual process that left to nature would find the barrier islands moving
landward each year allowing storms to dissipate their energy across them while
protecting the mainland. These islands along the shore have not been for the
most part left to nature. We have developed them, and to maintain them we are
locked in the endless programs of dredging and beach restoration to maintain
the white sand beaches that are tourist attractions.
In nature, barrier islands provide protection for the mainland
against flooding. However when we build beach front property on the barrier
islands it is only protected by the fragile sand dunes. Erosion of beaches and
dunes that serve as the defense for these coastal communities against storm
surge and flooding, increase the risk of destruction of coastal property,
infrastructure, and public safety during storms. The recent storm surge from
Hurricane Sandy at 13 feet above normal tides dwarfed the 6 foot surge of
Hurricane Donna in 1960. Many of the sandy beaches
along the Atlantic Coast have become increasingly vulnerable to storm damage
due to erosion of the beaches during past storms, despite the constant beach
restoration projects. Hurricanes Sandy, Irene (2011) and Ida (2009), as well as
large northeaster storms in 2007 and 2005 appear to be winning the battle of
the beaches.
Elevated water levels and waves during tropical storms can lead to
dramatic coastal change through erosion of beaches and dunes. Wave dominated
estuaries often have a sand bar or sand spit across the mouth of the estuary.
This sand bar breaks the force of the waves and physically protects the
estuarine lagoon from wind and waves. That is their purpose in nature, but when
you build multi-million dollar homes and high rises with roads that serve as
passageways for waters of the tidal surge on the sand bar and use the
tributaries for disposal of human and chemical waste, the resilience of the
estuary is destroyed.
Like all estuaries, barrier islands are an incredibly complex
ecosystem that we are only beginning to understand. Estuaries are productive
ecosystems and habitats determined by geology, salinity and climate. In the
United States the ecology of estuaries has been severely damaged by man because
most of our large coastal cities are built where rivers meet the oceans on
estuaries. Over half of the population of the country lives within cities and
suburbs build within or adjacent to these estuaries. Diverting fresh water from
tributaries for irrigation and drinking water supplies changes flow, quantity
of fresh water entering the estuary, and impacts the balance within the
ecology. Excess nutrients and sediment from sewage treatment plants, farm
fields and animal pastures, urban and suburban run off from roads and
landscaping can cause eutrophication. As the ecosystem of estuaries declines,
species die out, coastlines experience excessive erosion by wind, tidal action
and ice. The day will come when we no longer have the resources to continue
to rebuild on the Barrier Islands- for now just add it to the tab.
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| Neponsit Before Hurricane Sandy USGS |
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| Neponsit After Hurricane Sandy USGS |
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