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= How do you fill a beach? =
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[[File:Bigbeach.jpg|thumb|390px|Beach fill project under construction]]
 
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The majority of beach fill projects involve mining or dredging sand from an offshore source, transporting it to the beach and bulldozing the fill from 100 to 250 ft out into the water. It is an intensive construction project and each part of this process can harm the local environment. This section will briefly describe each part of the process and highlight the potential environmental effects.
 
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== Shoreline Impacts of Sea Level Rise ==
 
 
 
Many of us cheer on those swells generated by big storms, whether North Pacific winters on the West Coast, Hurricanes in the fall, or Nor’easters along the Atlantic seaboard.  But of course our fun waves often come with a price, eroding the shorelines and beaches that offer a buffer between the powerful oceans and the land that we live on.  When too much erosion happens too quickly our homes, streets and public works can be threatened or undermined if they were constructed too close to the waves.  There is a constant struggle in many places to keep the sea at bay, whether building concrete seawalls and other structures, or dredging up sand from the seafloor to dump on beaches. 
 
 
 
'''Increased Shoreline Erosion'''
 
Throughout history the oceans have slowly risen, chewing away at the land, but thanks to warming seas due to climate change, that rise in water levels is predicted to continue and accelerate well into the next century.  During storms there are already many areas that suffer from flooded streets and threats of erosion.  Imagine raising the water level an additional 2-4 feet and that flooding could be drastically exacerbated.  When you have massive storm swells riding on top of those higher water levels, damaging waves are more likely to erode the shore more quickly with devastating affects on shoreline developments.  In low-lying areas, like the barrier islands that form much of the East and Gulf coasts, the damage can be particularly heavy as natural sand movements and replenishment cannot keep pace with accelerated erosion.
 
 
 
Most developed coasts and beaches have buildings very close to the sea leaving little room for the ever-expanding ocean.  [http://www.eurekalert.org/pub_releases/2011-02/uoa-rsw021411.php Recent research] by scientists at the University of Arizona found that rising seas will have devastating affects on major cities throughout the U.S., saying:
 
 
 
:The Gulf and southern Atlantic coasts will be particularly hard hit. Miami, New Orleans, Tampa, Fla., and Virginia Beach, Va. could lose more than 10 percent of their land area by 2100.
 
 
 
They analyzed land elevations to determine the amount of space that lies within the expected rise in seas, creating a high-resolution map that can be used by communities to help their future planning in light of their risks.  Take a look at what might happen where you live.
 
 
 
[[File:Interactive SLR map Gulf Coast.png|thumb|500px|This map shows coastal areas in the Southeast that are threatened by different levels of sea level rise.  Go to http://climategem.geo.arizona.edu/slr/us48prvi/index.html to find your own state or town on this interactive map to see how your community might fare with predicted sea level rise.]]  
 
 
 
 
 
In the face of eroding beaches, owners of beachfront property will often try to use their political influence to demand that "something be done." The intelligent action would be to move the building away from the ocean. Unfortunately, what has often been done in the past has been to armor the coastline with rocks, concrete and steel. This does not protect or maintain the beach - it only protects the buildings.  When protective seawalls are built, the beach in front of them will slowly narrow in the face of sea level rise, eventually leading to a complete loss of that beach.
 
 
 
'''Loss of Wetlands and Flooding'''
 
We saw during Hurricane Katrina the impacts that wetland loss played by not having that natural “sponge” to absorb the higher water levels.  As sea levels continue to rise we are likely to lose even more wetlands and marshes making the impacts of storms on the coast even worse.  Wetlands provide habitat for many species, play a key role in nutrient uptake, serve as the basis for many communities’ economic livelihoods, provide recreational opportunities, and protect local areas from flooding.  They can naturally migrate with changing conditions over long periods of time. As the sea rises, the outer boundary of these wetlands will erode, and new wetlands will form inland as previously dry areas are flooded by the higher water levels. But if things change too quickly these critical habitats will get squeezed out of the picture.  This can lead to loss of not just natural protection from storms, but also important nursery areas for many types of fish and seafood.
 
 
 
Many barrier islands are backed by large lagoons and sounds.  The water levels here will also rise, threatening to flood the islands not just from the ocean side, but from behind.  This “inundation” can swamp homes, streets and sewer infrastructure causing permanent land loss and incredible pollution problems.  There is also the risk of saltwater tainting our water supplies by intruding into the groundwater.
 
 
 
'''Conclusion'''
 
It is critical that community planners make informed decisions when deciding how to react to rising sea levels.  The wrong choices could lead down a path where beaches disappear, coastal tourism and fisheries suffer or where billions of dollars are lost to storm-damaged and flooded properties.  Luckily, several states have adopted policies to ensure that beaches, dunes, or wetlands are able to migrate inland as sea level rises.  Much more needs to be done, though, and it is upon us to push our decision-makers to plan wisely and make the right decisions for the future of our coast.
 
 
 
 
 
== Sea Level Rise Adaptation Resources ==
 
 
 
* NOAA Coastal Services Center [http://www.csc.noaa.gov/climate/ Hazards and Climate Adaptation] – “helps communities take the steps needed to reduce harm to their communities and the planet. Commonly known as adaptation planning, a wide array of tools and services are available to help communities through this process”
 
 
 
* NOAA’s [http://collaborate.csc.noaa.gov/climateadaptation/ Coastal Climate Adaptation] – hundreds of community level resources, references, case studies and outreach materials
 
 
 
* Surfrider’s State of the Beach Erosion Response (contains SLR adaptation discussion) – evaluates each state’s adaptation efforts and provides links to relevant info and tools.  Direct links to each state's page are here:
 
 
 
::'''West Coast''': [[State_of_the_Beach/State_Reports/AK/Erosion_Response|Alaska]], [[State_of_the_Beach/State_Reports/BC/Erosion_Response|British Columbia]], [[State_of_the_Beach/State_Reports/CA/Erosion_Response|California]], [[State_of_the_Beach/State_Reports/OR/Erosion_Response|Oregon]], [[State_of_the_Beach/State_Reports/WA/Erosion_Response|Washington]]
 
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::'''Islands''': [[State_of_the_Beach/State_Reports/HI/Erosion_Response|Hawaii]], [[State_of_the_Beach/State_Reports/PR/Erosion_Response|Puerto Rico]]
 
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::'''Great Lakes''': [[State_of_the_Beach/State_Reports/IL/Erosion_Response|Illinois]], [[State_of_the_Beach/State_Reports/IN/Erosion_Response|Indiana]], [[State_of_the_Beach/State_Reports/MI/Erosion_Response|Michigan]], [[State_of_the_Beach/State_Reports/MN/Erosion_Response|Minnesota]], [[State_of_the_Beach/State_Reports/OH/Erosion_Response|Ohio]], [[State_of_the_Beach/State_Reports/PA/Erosion_Response|Pennsylvania]], [[State_of_the_Beach/State_Reports/WI/Erosion_Response|Wisconsin]]
 
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::'''Gulf States''': [[State_of_the_Beach/State_Reports/AL/Erosion_Response|Alabama]], [[State_of_the_Beach/State_Reports/LA/Erosion_Response|Louisiana]], [[State_of_the_Beach/State_Reports/MS/Erosion_Response|Mississippi]], [[State_of_the_Beach/State_Reports/TX/Erosion_Response|Texas]]
 
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::'''Northeast''': [[State_of_the_Beach/State_Reports/CT/Erosion_Response|Connecticut]], [[State_of_the_Beach/State_Reports/ME/Erosion_Response|Maine]], [[State_of_the_Beach/State_Reports/MA/Erosion_Response|Massachusetts]], [[State_of_the_Beach/State_Reports/NH/Erosion_Response|New Hampshire]], [[State_of_the_Beach/State_Reports/NY/Erosion_Response|New York]], [[State_of_the_Beach/State_Reports/RI/Erosion_Response|Rhode Island]]
 
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::'''Mid-Atlantic''': [[State_of_the_Beach/State_Reports/DE/Erosion_Response|Delaware]], [[State_of_the_Beach/State_Reports/MD/Erosion_Response|Maryland]], [[State_of_the_Beach/State_Reports/NJ/Erosion_Response|New Jersey]], [[State_of_the_Beach/State_Reports/VA/Erosion_Response|Virginia]]
 
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::'''Southeast''': [[State_of_the_Beach/State_Reports/FL/Erosion_Response|Florida]], [[State_of_the_Beach/State_Reports/GA/Erosion_Response|Georgia]], [[State_of_the_Beach/State_Reports/NC/Erosion_Response|North Carolina]], [[State_of_the_Beach/State_Reports/SC/Erosion_Response|South Carolina]]
 
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* [http://maps.google.com/maps/mapplets?moduleurl=http://www.heywhatsthat.com/mapplets/sealevel.xml Google Maps Visualization Tool]  - global analysis showing areas that could be subject to inundation with sea level rise
 
 
 
* Pacific Institute Study on [http://www.pacinst.org/reports/sea_level_rise/ The Impacts of Sea-Level Rise on the California Coast] – “concludes that sea-level rise will inevitably change the character of the California coast, and that adaptation strategies must be evaluated, tested, and implemented if the risks identified in the report are to be reduced or avoided. Populations and critical infrastructure at risk are shown in detailed maps prepared by the Pacific Institute available online here.
 
 
 
* CA Coastal Commission [http://www.coastal.ca.gov/climate/climatechange.html Climate Change Resources]
 
 
 
 
 
* '''Surfrider Chapter Managed Retreat Examples'''
 
:• Surfer’s Point: Ventura Rivermouth
 
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:– Paul Jenkin
 
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:– http://www.surferspoint.org
 
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:• Goleta County Beach: Santa Barbara
 
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:– Scott Bull
 
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:– http://santabarbara.surfrider.org/
 
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:• Sloat: Ocean Beach
 
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:– Bill McLaughlin
 
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:– http://sloaterosionob.blogspot.com/
 
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* '''Sea Level Rise activities for volunteers'''
 
:350.org Connect the Dots: http://connect.climatedots.org/
 
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:Preparing for Sea Level Rise: http://sealevel.climatecentral.org/responses/plans/
 
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:CA King Tides Initiative: http://www.californiakingtides.org/
 
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:WA King Tides Initiative: http://www.ecy.wa.gov/climatechange/ipa_hightide.htm
 
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:OR King Tides Initiative: http://www.climateadaptationplanning.net/kingtides/
 
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:Blue Line Project: http://www.bluelineproject.org/about.php
 
  
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'''Dredging and Mining'''
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[[File:Dredge at oceanside harbor 2006-04-12.JPG|390px|thumb|right|This cutterhead suction dredge is used for channel maintenance at Oceanside, CA Harbor.  Sediments from the channel are pumped onto nearby beaches.]]
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Approximately 95% of beach fill sand comes from offshore deposits<ref name="NRC">Beach Nourishment and Protection.  National Research Council.  National Academy Press.  1995.</ref>. Sand from these offshore “borrow sites” is usually dredged and piped from the source site to the beach and bulldozed into place. Sand dredged from beyond the 3-mile state limit on the Outer Continental Shelf (OCS) is managed by the [http://www.boem.gov/Non-Energy-Minerals/Marine-Minerals-Program.aspx Marine Minerals Program] of the US Bureau of Ocean Energy Management. Sand is also dredged from inlets, estuaries, lagoons and adjacent beaches where sand accretes. Some of these sources are less common because they sometimes cost more and contain sand that is too fine to use as “beach quality” sand. Other potential sources on land are sand from inland quarries and sand cleaned out of debris basins that trap sediment from floods. Sand dredging and mining have many potential environmental impacts, which a subsequent section will describe in detail.
  
  
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'''Sand Fill'''
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<iframe src="http://player.vimeo.com/video/14653210" width="400" height="300" frameborder="0" align="right"></iframe>
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</html>
  
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After dredging or mining sand, the beach fill is transported by truck or pipeline and then pumped as a slurry into large piles on the beach. Bulldozers then push the fill out into the planned artificial profile. Some beach fill projects deposit most sand into nearshore sandbars (berms) under the assumption that currents will move sand onto the beach. These activities also have many environmental effects associated with them that will be discussed below.
  
'''Key Terms'''
 
  
'''Resilience''': The ability of a community to cope with damage or change
 
  
'''Vulnerability''': Sensitivity to a hazard
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'''Other variations'''
  
'''Adaptation''': How to adjust to changing conditions
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Some beach fill projects are referred to under names such as sand recycling or sand bypass. Sand recycling projects dredge sand from an area where it accumulates and move it to “refill” the area that eroded. Sand bypass systems move sand past a structure that restricts the flow of sand along the coast, commonly a jetty. Sand is dredged on one side of the structure and then pumped onto on the other side. Some sand recycling or sand bypass systems are permanently installed on the beach and are designed to replace the natural sand flow.
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Revision as of 13:52, 9 July 2013

How do you fill a beach?

Beach fill project under construction

The majority of beach fill projects involve mining or dredging sand from an offshore source, transporting it to the beach and bulldozing the fill from 100 to 250 ft out into the water. It is an intensive construction project and each part of this process can harm the local environment. This section will briefly describe each part of the process and highlight the potential environmental effects.

Dredging and Mining

This cutterhead suction dredge is used for channel maintenance at Oceanside, CA Harbor. Sediments from the channel are pumped onto nearby beaches.

Approximately 95% of beach fill sand comes from offshore deposits[1]. Sand from these offshore “borrow sites” is usually dredged and piped from the source site to the beach and bulldozed into place. Sand dredged from beyond the 3-mile state limit on the Outer Continental Shelf (OCS) is managed by the Marine Minerals Program of the US Bureau of Ocean Energy Management. Sand is also dredged from inlets, estuaries, lagoons and adjacent beaches where sand accretes. Some of these sources are less common because they sometimes cost more and contain sand that is too fine to use as “beach quality” sand. Other potential sources on land are sand from inland quarries and sand cleaned out of debris basins that trap sediment from floods. Sand dredging and mining have many potential environmental impacts, which a subsequent section will describe in detail.


Sand Fill <html> <iframe src="http://player.vimeo.com/video/14653210" width="400" height="300" frameborder="0" align="right"></iframe> </html>

After dredging or mining sand, the beach fill is transported by truck or pipeline and then pumped as a slurry into large piles on the beach. Bulldozers then push the fill out into the planned artificial profile. Some beach fill projects deposit most sand into nearshore sandbars (berms) under the assumption that currents will move sand onto the beach. These activities also have many environmental effects associated with them that will be discussed below.


Other variations

Some beach fill projects are referred to under names such as sand recycling or sand bypass. Sand recycling projects dredge sand from an area where it accumulates and move it to “refill” the area that eroded. Sand bypass systems move sand past a structure that restricts the flow of sand along the coast, commonly a jetty. Sand is dredged on one side of the structure and then pumped onto on the other side. Some sand recycling or sand bypass systems are permanently installed on the beach and are designed to replace the natural sand flow.

  1. Beach Nourishment and Protection. National Research Council. National Academy Press. 1995.