“We are on a journey through the unknown,” said Evamaria Koch, a Brazilian-born scientist, who came to Maryland for her doctoral work and became captivated by the Chesapeake’s shorelines and submerged aquatic vegetation.
Speaking in Cambridge, MD, on the second day of the Mid-Atlantic Living Shoreline Summit, she was referring to her research on the effects of shoreline structures on SAVs and to the wider question of the effectiveness of shoreline defense strategies.
Koch could have been talking about any scientific inquiry, but her statement had special resonance for the more than 300 attendees who had braved snow and ice to spend a couple of days sharing knowledge and building community in support of living shorelines — one of the most promising tools that has emerged for protecting coastal properties from sealevel rise while enhancing habitat and ecological systems.
Summit organizers had hoped that the two days would be an opportunity to share research, tools and techniques as well as to discuss how to use this information to energize state and local programs in the mid-Atlantic region. What emerged after two days was consensus that more communication is needed to persuade property owners and governments to use living shorelines as the method of choice for sealevel adaption in coastal communities.
But it was also apparent that, while more research is needed to understand the long-term performance of these systems, policy development can’t wait for the results.
The summit, like a similar summit in 2007, was attended by marine contractors, regulators, policy-makers, scientists, homeowners, engineers, consultants and members of nonprofit groups. The summit included small-group table discussions organized around different interests or alignments, such as regulators, researchers or practitioners. While there appeared to be no disagreement that traditional hardened shorelines accelerate the damage done by sealevel rise to property and reduce nature’s ability to protect them through natural systems, what constitutes a living shoreline remains open to debate, largely because the science is evolving.
The Maryland Department of Natural Resources acknowledged that definitions continue to change. The DNR describes the living shoreline practice as a “suite of shoreline erosion control measures that can be used to minimize coastal erosion and maintain coastal processes…techniques [that] are used to protect, restore, enhance or create natural shoreline habitat.”
According to The Nature Conservancy, living shorelines provide “long-term protection, restoration or enhancement of vegetated shoreline habitats through strategic placement of plants, stone, sand fill and other structural or organic materials.”
Most agree that living shorelines must contain substantial “living” elements. These natural habitat elements can include emergent marsh grasses, submerged aquatic vegetation, riparian vegetation, coarse woody debris or oyster reef and shell.
The conservancy and others stress that structures that sever the natural processes between aquatic areas and the adjacent uplands should not be considered living shorelines. But what these natural processes are and how to best preserve them can be difficult to ascertain, said some, because much of the Chesapeake Bay and its tidal rivers are already vastly altered.
Intermittent or continuous lengths of riprap revetments, bulkheads and seawalls “harden” many stretches of the coast. In highly urbanized areas, most natural system have been altered. Kevin Du Bois, from the city of Norfolk said, “Norfolk has virtually no natural shoreline.”
The definition of living shorelines is more than a semantic issue, as discussions over the course of the summit revealed the interplay between science, policy and implementation.
Researchers formulate their hypotheses around questions of ecological function, for example, how to promote the growth of benthic animals in the subtidal region with different construction materials. Documenting this growth is key to understanding how well living shorelines restore or conserve vital ecological function.
But scientists must test their hypotheses on manmade systems that use more — or less — natural features. And these features, because they are living, change over time, usually for the better. And no two living shorelines are exactly alike or experience identical tidal, climatic and upland conditions. The effectiveness of 1,000 feet of a living shoreline system, when flanked by bulkheads on either side, can be diminished.
Sadie Drescher, from the Center for Watershed Protection, serves on the Chesapeake Bay Program’s expert panel for shoreline management. She discussed the challenges in the face of uncertain performance data of developing protocols that would allow a shoreline locality to get credits for reducing sediment to the Bay using living shorelines.
Both regulators and policy makers stressed the need for long-term monitoring data that would help identify how well these systems meet ecological functions, such as improving local water quality. Design engineers agreed, noting the need for a modeling tool based on existing performance data that could be used to better understand living shorelines along a reach or in an embayment.
Despite the many unanswered questions, the science has progressed remarkably, said Jeff Benoit, executive director Restore America’s Estuaries, a Washington, DC-based nonprofit that helped secure funding for the summit.
“I came away amazed at how many scientists have really taken on studying living shorelines, and I am also amazed at how many new programs have sprung up since the last conference in 2007.”
But, Benoit said, encouraging private landowners to choose these systems remains a hard sell. In spite of ample evidence that living shorelines can provide better protection from damaging storm surge and winds, property owners remain skeptical. They see their neighbors putting in rock revetments, and to them, it just “feels more secure.”
Keynote speaker, Margaret Davidson, from the National Oceanic and Atmospheric Administration’s Ocean and Coastal Resource Management office, suggested that using the term, “natural defenses” instead of “living shorelines” might have more resonance with a wider audience.
A panel of marine contractors talked about the business side of living shorelines, spurring a lively discussion with the audience. John Flood of Flood Brothers Marine Consultants, said, “Contractors can be the best ambassadors for living shorelines.”
Generally, homeowners contact them first when looking for shoreline protection. “We tell homeowners about what works and what doesn’t.” But, he said, “You have to be honest and be ready to tell them — if it’s true — that their site just isn’t right for a living shoreline system.”
Keith Underwood, of Underwood & Associates, spoke about the challenges of executing shoreline projects, from gaining construction access to permitting issues. While efforts to streamline the permitting process have been undertaken in Maryland and Virginia, each state has a different system, and there are no consistent design standards.
Panel members acknowledged the dilemma between needing the flexibility to design to specific sites, while trying to meet permit requirements that are generally so prescriptive that they can be difficult to meet.
Many presenters reminded the larger group that shoreline erosion is a natural process. In the Chesapeake Bay, for example, one third of all shorelines are classified as eroding.
People have chosen to build on the shoreline and want to protect their property. Karen Durhling from the Virginia Institute of Marine Science noted that continued coastal development reinforces the expectation that this type of development should be protected.
But Rob Young, coastal processes researcher from Western Carolina University, suggested that attendees consider, “Should we be building here to begin with? Shouldn’t a strategic retreat from the coastlines be part of [our broader] conversation?”
Days before the summit began, Matthew Kirwan of VIMS and Patrick Megonigal of the Smithsonian Environmental Research Center published a report documenting the resiliency of coastal wetlands — and the many ways that human activities alter their ability to serve as a defense against sealevel rise.
Tracy Skrabal, a coastal scientist and manager of the North Carolina Coastal Federation’s southeast regional office, said after the conference, “everybody has their favorite ecosystem. There are riparian buffer folks, benthic people and SAV folks. The trick is to bring them and all the information together. These kinds of conferences are really good for this.”
Kevin Smith from the Maryland Department of Natural Resources and chair of the summit steering committee, agreed. “There’s an awful lot of information out there, and the trick is to synthesize the information and get it to the folks who manage and regulate. We need to vastly improve this.”
The pace of sealevel rise and coastal erosion are accelerating the iterative cycle between scientific research and policy development. As Davidson reminded conference attendees, “Today’s flood is tomorrow’s high tide.”
It was clear that those who attended the conference are not inclined to stick their heads in the sand about the urgency of addressing the impacts of sealevel rise. But it can be difficult to maintain perspective. Smith said, “We’ve made a lot of progress since 2006. Sometimes when you’re in the middle of things, you can’t see the progress. I feel very positive about the trajectory of our path.”