By LIZ DURKEE
Humans are not the boss of nature. Just ask the residents of western Massachusetts, Joplin, Missouri, or Japan. On the Vineyard we are at the constant mercy of wind, waves, storms and tides. Someone once said that when land and water wrestle, water always wins. That's why it was refreshing to hear talk, at an erosion control workshop on the Island last week, of erosion management as opposed to erosion control.
The Vineyard and Nantucket are ground zero when it comes to coastal erosion and sea level rise in the United States, according to environmental attorney Glenn Wood, a speaker at the June 7 workshop. This has to do with the impacts of global warming on the oceans and our specific location at the tail end of the Gulf Stream. The northeast coast, he said, may see a higher-than-average rate of sea level rise and erosion, a four to eight-foot rise in sea level as opposed to the average three-foot estimate. Erosion control is out of the question.
Coastal erosion is a natural process. Beaches, banks and dunes are meant to erode, sending sand down-drift to build up other beaches. But the process is corrupted when humans are thrown into the mix. We build houses .and roads on a moving shoreline and then try to protect them. We build concrete seawalls and stone revetments, structures that block sand from entering the system, wash away the beaches in front of them and erode the properties on either side.
When we build groins out into the water to trap sand in place, we starve the down-drift beaches. Largely built in the early to mid-20th century, groins have become a dirty word in the world of coastal resource protection. Defined as hard engineering structures, they are no longer allowed. (Groins and jetties are similar structures; jetties are built to stabilize navigational channels such as harbor and pond inlets, while groins are designed specifically to trap shifting sand.)
But climate change–the result of global warming–is stealing away our valuable shoreline and it's time to look at how we can use existing groins to our advantage. Coastal geologist Jim O'Connell zeroed in on this concept at the workshop with a couple of choice phrases. He said "groins and beach nourishment are the way to go," and "sand is gold."
Sand is the new gold because beach renourishment–the human placement of sand on eroding beaches–is our best chance for at least short-term erosion management. It not only enhances the recreational value of beaches but helps protect upland buildings and roads. Still, beach nourishment projects are, as the saying goes, designed to fail, because sooner or later the sand will erode away and more will be needed to replace it. Except for the sand dredged from our coastal ponds and plunked back onto the beaches, sand is a dwindling resource. Massachusetts does not allow the mining of sand from the ocean for use on beaches. How will we define ourselves as a community and sustain ourselves as a viable economic entity without beaches, especially public beaches?
Hence the need to tweak existing groins to suit the needs of a vastly changing shoreline. Unlike Mr. O'Connell the coastal geologist, state and federal regulators are slow to face the fact that the old, maligned groins have the potential to be our new best friends. They can help keep a precious supply of sand where we need it most. Mr. O'Connell is a fan of old, loose, semi-functional groins that trap some sand but also let some creep through the crevices and wander down-drift.
Oak Bluffs is in the process of permitting a shoreline protection project for its downtown beaches, from the Oak Bluffs harbor all the way down Sea View avenue to the southern end of Inkwell Beach. The plan, if approved by state and federal regulators, includes major beach nourishment that will widen the current beaches and recreate beaches where they no longer exist–just north and south of the Steamship Authority dock. It also includes changing the size of the groins at Pay and Inkwell Beaches. If the groin between the two beaches is shortened and the groin south of Inkwell extended, more sand will drift onto Inkwell and stay there a little longer. Let's hope the regulators see the logic. Oak Bluffs is one of a few towns that have, and have the opportunity to enhance, a vital downtown beach front.
Workshop participants learned that for the third winter in a row there has been a dramatic increase in coastal erosion on the Vineyard due largely to relative sea level rise and coastal armoring. It's time for coastal planners to change the way we approach coastal erosion–from reactive to proactive.
This won't be easy. Private property owners want to protect their waterfront investments from coastal erosion, sometimes at the expense of others. Mr. Wood reported that hundreds of millions of dollars of Massachusetts shoreline real estate is at risk due to coastal erosion and sea level rise, that owning waterfront property adds 28 per cent to the value of the real estate, and that it is a natural instinct for property owners to preserve their investments. Some of the means by which they hope to do so, he said, like armoring the shoreline, puts other public and private buildings, roads, beaches, banks and dunes at risk.
Mr. Wood works for both towns and private property owners. He calls the coastal protection field of litigation the "Wild West." Can one property owner sue another, or a town, because a groin cuts off sand supply and puts a house at risk of damage or loss? The implications affect every Island taxpayer.
The National Oceanic and Atmospheric Administration (NOAA) reports that "coastal tourism and recreation provides a substantial positive economic benefit in the United States in terms of jobs, income, and governmental revenue." On the Island and elsewhere, tourism and public recreation is as important to the economy as private property protection.
What are the options for coastal erosion management? Soft solutions, as opposed to hard structures, are the new standard–beach nourishment and beach, bank and dune restoration. Another approach discussed at the workshop is water attenuation devices, artificial reefs built offshore to slow and dissipate wave action before it reaches the shore and causes erosion. Mr. O'Connell believes public beaches on the Island are a good place to test these experimental submerged breakwaters.
He also pointed out that the Vineyard still has an enormous amount of unarmored shoreline and recommended coastal protection setback ordinances. When it comes to problems like constantly eroding beach parking lots he said "off-site mitigation is the way to go; on-site mitigation is a money pit." In other words, move things away from the eroding shore whenever possible. Another very real alternative is to abandon some eroding shorelines.
Other erosion management options presented at the workshop include the following:
• Identify vulnerable infrastructure and natural resources in order to anticipate shoreline changes;
• Develop a management plan to mitigate impacts of coastal erosion;
• Develop short and long-term plans to relocate roads and buildings;
• Organize public outreach to educate residents about coastal processes and shoreline vulnerability;
• Consider the costs of short and long-term erosion control management goals.
Island planners have their work cut out for them, but they can't do so in a vacuum. Community involvement and local insight is critical to successful planning. Coastal erosion management is going to be expensive, but the costs will dramatically increase over time. Active, engaged planning is what we need on this hot little microcosm of climate change disruption.
This series of 14 essays about climate change was published in the Vineyard Gazette over a period of seven months in 2011. It appears here with permission. Copyright Vineyard Gazette. All rights reserved.