Here’s
What We Can Do
A century from now, the U.S. coastline will look very different
from how it looks today. In the coming decades our beaches, wetlands and estuaries along the shore will be lost or degraded by a one-two punch of more severe storms and rising seas.
This combination will drive communities inland and force the relocation of critical infrastructure. The consequences for fish, wildlife and ecosystems could also be devastating.
We’re already getting a glimpse of how bad things can get.
The three major storms of 2017 — Hurricanes Harvey, Irma and
Maria — caused more than 3,000 deaths and some $275 billion in
damages. The longer-term ecosystem impacts of major storms like
these are harder to quantify, but no less important.
These include shifting of beaches and dunes, saltwater intrusion to freshwater systems, ecosystems contaminated by polluted floodwaters, and damage to habitat, oyster beds and coral. Rising sea levels are steadily pushing storm damage farther inland.
These include shifting of beaches and dunes, saltwater intrusion to freshwater systems, ecosystems contaminated by polluted floodwaters, and damage to habitat, oyster beds and coral. Rising sea levels are steadily pushing storm damage farther inland.
The country has done surprisingly little to meet this daunting
challenge. As I wrote in my book A
New Coast: Strategies for Responding to Devastating Storms and Rising Seas,
there are steps that need to be taken now to help protect
coastal ecosystems and the communities that depend on them.
A first step toward better protecting beaches and coastal
wetlands is to understand the risks they face from storms and rising seas.
Scientists predict that as the climate warms, coastal storms
will become more intense and melting glaciers and
ice sheets could push global sea level up four feet by 2100. Along the U.S. coast, the
rise in sea level could be 15 to 25 percent higher due to land
subsidence and ocean dynamics.
What will this mean for ecosystems? It’s hard to know exactly.
There is currently no national assessment of how ecosystems along the U.S. coast will change. What little we do know points to serious decline in the health of these resources.
For example, a study of the Gulf of Mexico region predicted these losses of coastal wetlands by 2060: 37 percent in Texas, 32 percent in Florida, and 26 percent in Alabama and Mississippi. A 2017 study by the U.S. Geological Survey found that up to 31 percent of California beaches would be lost in the event of 3 feet of sea-level rise and 67 percent in the event of 6 feet.
As beaches and wetlands are inundated or migrate inland, some of
the ecosystem services they provide will be lost. We are likely to see
diminished abundance and diversity of fish and wildlife.
Other benefits of coastal ecosystems that are at risk include protection from the impacts of storm surges, protection of water quality, mitigation of coastal erosion, and sequestration of carbon.
Other benefits of coastal ecosystems that are at risk include protection from the impacts of storm surges, protection of water quality, mitigation of coastal erosion, and sequestration of carbon.
The effects of more severe storms and rising oceans on fish and
wildlife are not well studied, but the Center for Biological Diversity
(publisher of The Revelator) reported that 233 threatened and endangered
species in 23 coastal states — roughly 1 out of 6 of the country’s protected
species — are at risk from sea-level rise.
Manmade Threats
In addition to suffering damages from storms and gradual
inundation by rising seas, coastal ecosystems may fall victim to human efforts
to protect communities and infrastructure from these risks.
Built structures such as seawalls, damage beach systems
and can prevent healthy functioning of marshes and wetlands.
Living shorelines, which use natural materials such as plants, sand, or rock to stabilize the shoreline, are an improvement over conventional concrete seawalls but can have some of the same damaging impacts. Beach restoration projects can also harm the ecosystem of the beach as well as the sites from which sand is taken.
Living shorelines, which use natural materials such as plants, sand, or rock to stabilize the shoreline, are an improvement over conventional concrete seawalls but can have some of the same damaging impacts. Beach restoration projects can also harm the ecosystem of the beach as well as the sites from which sand is taken.
Still another manmade threat is the failure to provide space for
coastal ecosystems to migrate landward as seas rise. As the inevitability of
stepping back from the current coastline is better recognized, land areas that
are safe from storms and rising seas will be committed to meet human needs.
Ecosystems could lose out on this valuable space.
Strengthening Protections
So what do we do?
The good news is, we already have a lot of the tools and
programs we need to make sure that coastal ecosystems are protected as the
climate warms. For example, the Coastal Zone Management Program supports state
planning for coastal protection. But existing programs need to be strengthened
and expanded.
A key first step should be a careful mapping of existing coastal
ecosystems and of the potential for successful landward shift of these
resources.
With such an atlas in hand, governments and nonprofit organizations can identify upland areas that can become coastal ecosystems over time.
Special attention needs to be given to mapping fish and wildlife and assessing ecosystem services, so that gains or losses can be tracked and migration corridors protected as these ecosystems shift geographically.
With such an atlas in hand, governments and nonprofit organizations can identify upland areas that can become coastal ecosystems over time.
Special attention needs to be given to mapping fish and wildlife and assessing ecosystem services, so that gains or losses can be tracked and migration corridors protected as these ecosystems shift geographically.
Some coastal mapping initiatives are moving in this direction. For
example, the National Fish and Wildlife Foundation has developed a Regional Coastal Resilience Assessment that
identifies “resilience hubs” and other information to guide local conservation
planning. Likewise, the Southeast Conservation Adaptation Strategy includes
a “blueprint” that identifies places for conservation and restoration.
When it comes to diminishing manmade threats, some states have
restricted the use of seawalls and similar hard protection structures.
Development on some coastal wetlands is limited by the permit program under
section 404 of the Clean Water Act. Nonprofit organizations like the Nature
Conservancy are working to protect these resources though acquisition or
purchase of easements.
But that won’t be enough.
Protecting both existing ecosystems, and the areas these
ecosystems will migrate to, will require major new investment in planning and
significant new funding to implement plans.
Federal agencies will need to work with state and local
governments and nonprofit organizations to successfully manage a long-term
landward migration of coastal ecosystems. This will require creating a planning
process able to make hard decisions to find space to allow ecosystems to
migrate inland.
States and localities also need to consider alternatives to
seawalls and other coastal protection structures that pose barriers to inland
migration of coastal ecosystems.
Can flood waters from coastal storms be accommodated by elevating buildings or critical infrastructure? Is the permanent inundation that comes with rising seas better managed in the long-run by stepping back from the shoreline to safer ground?
The federal government needs to provide the science, policy guidance, and funding that state and local governments need to cope with these questions.
Can flood waters from coastal storms be accommodated by elevating buildings or critical infrastructure? Is the permanent inundation that comes with rising seas better managed in the long-run by stepping back from the shoreline to safer ground?
The federal government needs to provide the science, policy guidance, and funding that state and local governments need to cope with these questions.
Any effort to protect coastal ecosystems from more severe storms
and rising seas has a better chance of success if it occurs in the context of a
larger effort to protect communities and infrastructure from these risks.
For example, existing federal policies related to flood insurance and disaster relief need to be updated to reduce incentives to locate in risky coastal places.
This will reduce future demand for structural protection that harms ecosystems. New national policies to require disclosure of flood and sea-level rise risks to a property at time of sale would also help steer investment away from risky areas.
For example, existing federal policies related to flood insurance and disaster relief need to be updated to reduce incentives to locate in risky coastal places.
This will reduce future demand for structural protection that harms ecosystems. New national policies to require disclosure of flood and sea-level rise risks to a property at time of sale would also help steer investment away from risky areas.
Finally, the federal government should help coastal homeowners
avoid devastating financial losses as growing flood risks drive down property
values.
For example, the government could buy risky property well ahead of rising sea levels and allow current owners to stay — paying rent but not flood insurance premiums — until the property becomes unsafe.
Such a program would give these homeowners financial freedom to move to safer ground, reduce the chance of widespread structural protection projects, and expand options for landward migration of ecosystems as well as communities.
For example, the government could buy risky property well ahead of rising sea levels and allow current owners to stay — paying rent but not flood insurance premiums — until the property becomes unsafe.
Such a program would give these homeowners financial freedom to move to safer ground, reduce the chance of widespread structural protection projects, and expand options for landward migration of ecosystems as well as communities.
To increase the odds that healthy coastal ecosystems will line
the U.S. coast 100 years from now, governments and nonprofit organizations need
to act fast to ramp up existing protection efforts and be effective advocates
for these threatened resources.
Jeff Peterson worked at the
Environmental Protection Agency, U.S. Senate Committee on Environment and
Public Works, and White House Council on Environmental Quality and is author
of A New Coast: Strategies for Responding to Devastating Storms and
Rising Seas (Island Press, November 2019). https://islandpress.org/books/new-coast
