[Project Purpose] [Project Overview] [Project Design] [Project Benefits] [Environmental Review] [Construction]
ORIGIN: THE REBUILD BY DESIGN COMPETITION
In June 2013, the U.S. Department of Housing and Urban Development (HUD) launched Rebuild by Design (RBD), a competition to respond to Superstorm Sandy’s devastation in the northeast region of the United States and promote a design-led approach to proactive planning for long-term resilience and climate change adaptation The winning proposal would be implemented using Community Development Block Grant Disaster Recovery (CDBG-DR) funding as well as funding from the State of New York. In June 2014, following a year-long community-based design process during which the design teams met regional experts, including government entities, elected officials, issue-based organizations, local groups and individuals, HUD announced the winning proposals. The Staten Island Living Breakwaters Project which proposed a layered resiliency approach to promote risk reduction through erosion prevention, wave energy attenuation, and enhancement of ecosystems and social resiliency, was one of the selected projects. As a result, New York State has been allocated $60 million of CDBG-DR funds to help implement the project along the Tottenville section of the South Shore of Staten Island.
PROJECT PURPOSE: WHY LIVING BREAKWATERS?
In October 2012, Superstorm Sandy devastated Staten Island’s east and south shore neighborhoods. The driving wave action battered the coastline, damaging or destroying an unprecedented number of Staten Island homes and businesses, resulting in loss of life and significant harm to the local economy. Tottenville, a community at the southernmost point of Staten Island, experienced some of the most destructive waves in the region. Much of the shoreline has also experienced ongoing erosion over the last 35 years; in many locations, erosion rates average more than one foot per year and in one area of Conference House Park, they reach an average rate of more than three feet per year, leaving the area increasingly vulnerable. Historically known as “The Town the Oyster Built,” Tottenville was once protected by a wide shelf and series of oyster reefs, which in turn supported a robust oyster farming industry. Over time, due to siltation, overharvesting, channel dredging, and human pathogens in the water, the once abundant oyster reef collapsed. Today, the Raritan Bay lacks not only the oysters, but the complex habitat their reefs provided and the species richness and biodiversity that they supported. Without these natural systems, the shore of Staten Island remains exposed to wave action and coastal erosion and lacking this rich environmental resource. The Living Breakwaters are designed to:
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Risk Reduction: address both event-based and long-term shoreline erosion in order to preserve or increase beach width; attenuate storm waves to improve safety and prevent damage to buildings and infrastructure.
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Ecological Enhancement: Increase the diversity of aquatic habitats in the Lower New York Harbor / Raritan Bay (e.g., oyster reefs and fish and shellfish habitat), particularly rocky / hard structured habitat that can function much like the oyster reefs that were historically found in this area.
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Foster Social Resilience: Provide programming that builds a community around education on coastal resilience and ecosystem stewardship; foster and encourage community stewardship and citizen science, and enhance access to the water’s edge and near-shore waters for recreation, education, research, and stewardship activities.
PROJECT OVERVIEW: WHAT ARE LIVING BREAKWATERS?
Living Breakwaters is an innovative coastal green infrastructure project that aims to increase physical, ecological, and social resilience. Living Breakwaters consists of:
- Living Breakwaters: Approximately 2,400 linear feet of near-shore "breakwaters," or partially submerged rubble mound structures located between 790 and 1,800 feet from shore, designed to reduce risk and provide habitat for local marine life.
- Shoreline Restoration: One-time sand replenishment from Manhattan Street to Loretto Street, an area especially prone to erosion and where public and private assets are vulnerable.
- Active Oyster Restoration by the Billion Oyster Project: Work includes installations on the breakwaters themselves, a floating oyster nursery, off-site cultivation activities (hatcheries, remote setting, etc.), shell collection and curing.
- Programming: This includes educational, stewardship, and workforce training activities related to the other project elements. This includes STEM educational materials developed and hosted by the Billion Oyster Project.
The System
The Living Breakwaters function as a system of elements that work together to reduce risk and enhance habitat in the Raritan Bay. Each segment was individually designed to contribute to the overall system and achieve the desired performance. The breakwater system consists of a series of nine ecologically enhanced breakwater segments. and will include approximately 2,400 linear feet of breakwaters located between 790 and 1,800 feet from shore and in water depths of between two-and-10 feet below mean low water (NAVD88). In addition to the breakwaters themselves, the design includes a limited, strategic, one-time placement of shoreline restoration that will add needed sediment to the system and provide initial protection to the most vulnerable stretch of beach as the breakwaters work over time to accrete beach elsewhere. This layout was refined through the process of design and computer modeling, where scenarios were iteratively developed, modeled to evaluate impacts on shoreline change and storm wave attenuation, and the results analyzed to help inform the design refinement and optimize the design to reduce or reverse erosion (grow beach) and reduce coastal storm risk through wave attenuation.
Individual Breakwaters
The breakwaters are rubble mound (rock) structures with a stone core, a base layer (bedding stone or marine mattress, depending on the breakwater) to protect against scour, and outer layers consisting of armor stones and ecologically enhanced concrete armor units. These ecologically enhanced concrete units are located in the intertidal and subtidal areas of the breakters and are specially designed to promote biological activity and promote recruitment of marine species. This is achieved through both the specialized concrete mixture and the design of the textured surfaces of the units.
In addition to the main (traditional) breakwater segment, the Living Breakwaters will have “reef ridges”—rocky protrusions on the ocean-facing sides of the breakwaters—and “reef streets”—the narrow spaces between the reef ridges. These features create localized modifications to wave behavior and provide a diversity of habitat characteristics to generate opportunities for species recruitment. Habitat diversity is further enhanced on the reef ridges through greater variation in rock sizes and the spaces between them, the textured surfaces of the ecological concrete armor units, and the inclusion of ecological concrete tidepools in the intertidal zone.
Oyster Restoration
Once the breakwaters are constructed, the Billion Oyster Project will install live oysters on the breakwaters. Techniques may include placing spat (baby oysters) on some of the ecologically enhanced concrete units, installing oyster shell gabions (non-structural units), placing spat on shell in the reef streets, and in-situ setting pilots. The oyster gabions and spat-on-shell installation will use designs and techniques that have been employed on other oyster restoration projects throughout the Harbor.
BENEFITS OF LIVING BREAKWATERS?
Building Physical Resilience
The Living Breakwaters are designed to reduce the risks of storm wave attack and long-term erosion; hazards threaten the health, safety, quality of life, and sustained existence of the waterfront neighborhoods of Tottenville, Conference House Park, and the historic and ecological resources it contains. Extensive computer and physical modeling was performed to understand the impacts of the breakwater system on shoreline change and wave action in order to optimize these risk reduction benefits. Wave attenuation benefits from the breakwaters were evaluated through extensive hydrodynamic wave modeling. The breakwaters are designed to reduce waves reaching on-shore buildings and roads to below 3 feet in height in the event of a 100-year storm assuming up to 18 inches of sea level rise. The modeling also indicates that the breakwaters will continue to provide risk reduction through wave attenuation at higher levels of sea level rise as compared to a no-breakwaters scenario, even if they become permanently submerged. The breakwater system is also designed to capture sediments along the shoreline, reducing historic shoreline erosion and in most places actually widening the beach over time. This wider beach will provide additional protection from erosion and wave action to buildings, infrastructure, parks, and natural features.
Growing Ecological Resilience
The Living Breakwaters are specially designed to provide complex structured subtidal and intertidal habitat, with the aim of providing the diverse mosaic of habitat conditions needed to catalyze increased biodiversity and restore ecosystem services once provided by oyster reefs in Raritan Bay. The habitat enhancements are consistent with existing regional plans and priorities such as the Hudson Raritan Estuary Comprehensive Restoration Plan (HRE CRP) The introduction of complex, rocky habitat with extensive pore space augmented with a suite of environmentally sensitive design modifications and materials, create ecological niches usually absent from standard breakwater structures. Closely spaced rocky intertidal / subtidal protrusions (reef ridges) create “reef streets” which add habitat complexity and dramatically increase the surface area of productive intertidal and shallow subtidal habitat provided by the breakwaters. The integration of bioenhancing concrete units into the armor units of the main body of the breakwater segments as well as the reef streets adds greater range of crevice sizes and promotes biogenic buildup to further enhance the overall complexity and variety of the rocky habitat created. Eventually, active oyster restoration on and around the breakwaters will provide added habitat variety, complexity, and biodiversity and contribute to regional restoration goals (HRE CRP). Together, these strategies help the project maximize the ecological uplift provided and help offset any impacts to existing habitats or species. The following section provides a summary of the habitat benefits and potential impacts provided by the breakwaters.
Fostering Social Resilience
The calmed near shore waters and wider beaches created by the breakwaters will not only help reduce risk from coastal storms but will also enhance recreational opportunities along the shoreline including boating, fishing, and general beach use. Programming and education are a critical part of the Living Breakwaters social resiliency project objectives, allowing for residents and visitors to engage with the shoreline, learn about resiliency initiatives and ecological restoration activities, and become stewards of the harbor. The Billion Oyster Project has also developed a Living Breakwaters STEM Curriculum designed for students in 6th to 8th grade public school science classes, emphasizing the history and importance of oysters to Staten Island and its ecology, and showcasing the Living Breakwaters as a case study in coastal resilience. The curriculum, which you can access here, explains how the breakwaters will increase the area’s resiliency and how they will contribute to a healthier environment. In 2019, BOP worked with teachers in more than a dozen schools in Staten Island and nearly 50 city-wide and plans.
The Environmental Impact Statement (EIS) process was completed in 2018 with the publication of the Joint Record of Decision and Finding Statement of the Coastal and Social Resiliency Initiatives for Tottenville. It can be found on the Environmental Documents page of the GOSR Web site by scrolling down to the Rebuild by Design section. The project also requires permits from the U.S. Army Corp of Engineers (USACE) and the New York State Department of Environmental Conservation (DEC).
Plans for Construction
A construction contract for the project has been executed with Weeks Marine. Please check back for construction updates as they become available.
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