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Breaking Down Barriers: Natural Infrastructure

NOAA Ocean Podcast: Episode 17

Natural infrastructure provides effective solutions for minimizing coastal flooding, erosion, and runoff, but it has other benefits as well. In this episode, Kim Penn from NOAA’s Office for Coastal Management explains the environmental, economic, and recreational benefits of natural infrastructure.

Aerial photo of the Mississippi coast with a living shoreline project that includes natural and artificial breakwater material and marsh creation to reduce shoreline erosion.

This aerial photo shows the Mississippi coast with a living shoreline project that includes both natural infrastructure and artificial breakwater material to reduce shoreline erosion. Living shorelines help reduce coastal risks and improve resiliency through an integrated approach that draws from the full array of coastal risk reduction measures. Using solely "gray," or hardened infrastructure, can negatively impact coastal habitats, be visually obstructive, and result in higher up-front costs.


HOST: This is the NOAA Ocean Podcast. I’m Abby Reid. What can protect coastal communities, conserve natural habitats, and provide economic benefits throughout the U.S.? The answer is natural infrastructure. ​Coastal natural infrastructure includes​ wetlands, sand dunes, and reefs, as well as man-made systems that are engineered to work like natural ecosystems, ​such as living shorelines. Studies have shown that implementing these systems can buffer waves during storms, increase recreation and tourism opportunities, reduce runoff, and provide many other benefits to both inland and coastal communities. NOAA’s Office for Coastal Management is the federal office that partners with coastal states and territories to implement the Coastal Zone Management Act. I sat down with Kim Penn from the Office for Coastal Management to learn more about what natural infrastructure is, how it works, and why it’s important to our communities and to our economy​. Hi Kim, and welcome.

KIM PENN: Thank you for having me.

HOST: Can you tell me and our listeners a little bit about what you do at NOAA?

KIM PENN: I personally focus on coastal resilience for our policy team, and one of my current priorities is advancing the use of natural infrastructure for resilient coastal communities.

HOST: Can you talk a little bit about what the term “natural infrastructure” means?

KIM PENN: I’m glad that you asked.

Natural infrastructure is a term that we use to talk about the natural environment. It can include wetlands, forests and beaches, and also systems that are engineered or built to mimic natural ecosystem functions or processes. Sometimes we do get more specific and call those latter engineered systems “nature-based” infrastructure – and they would include things like rain gardens and living shorelines.

HOST: Can you talk a little bit more about the difference between “natural infrastructure” and “nature-based” infrastructure?

KIM PENN: Sure. So natural infrastructure can include wetlands, forests, beaches, dunes, mangroves, coral reefs, oyster reefs. Natural infrastructure approaches or solutions associated with those systems include conservation, protection, or restoration of those habitats.

Nature-based infrastructure is typically used when we’re talking about a more engineered landscape or system. And so it would include things like rain gardens, green roofs, bioswales, and permeable pavement. Those are all examples of stormwater management techniques that incorporate natural processes.

Another popular nature-based approach is a living shoreline. A living shoreline is a protected, stabilized coastal edge, constructed from more natural materials, which can include marsh plantings or stone sills, restored oyster reefs.

So, in my office, we are looking to advance the use of natural and nature-based infrastructure in coastal communities, because in addition to providing the benefits that you typically think of with natural systems – which include recreation and habitat, all the things that we enjoy going out into nature for – these systems provide really effective solutions for minimizing coastal flooding, erosion, and other hazards.

HOST: It sounds like “natural” and “nature-based” techniques really do a great job of strengthening coastal communities and making them more resilient in the face of natural hazards.

KIM PENN: Absolutely.

HOST: So what is resilience?

KIM PENN: So resilience is the ability of a community to prepare for and respond to extreme weather events, climate hazards, or changing ocean conditions. We also sometimes say it’s the community’s ability to bounce back after events such as hurricanes, coastal storms, or coastal flooding – in addition to just responding to those immediate impacts.

We think of resilience as really critically important to our coastal communities. It provides the ability to prevent a short-term hazard event from turning into a longer-term community-wide disaster.

HOST: How exactly can natural systems protect communities from natural hazards?

KIM PENN: So existing coastal natural areas, such as wetlands or dunes, can help absorb flood waters and lessen the impacts of waves.

Over the past few years, after Hurricanes Katrina and Sandy, we've heard of the importance of coastal wetlands in southern Louisiana and off the coast of New York City.

We have some success stories of locations where we saw that in tact dune systems or coastal wetlands, areas that were, communities that were behind these impact coastal systems fared better than those that were not. Also, in more urban areas, nature-based infrastructure, such as rain gardens, can help with stormwater management, including absorbing runoff during rain events, protecting water quality, and storing excess water to prevent flooding in the streets.

Living shorelines can also help lessen the impact of waves and reduce shoreline erosion. One of the obvious benefits of natural infrastructure is wildlife habitat, but also recreation, like hiking, fishing and bird watching, natural areas can help to filter water, they are beautiful to look at, and they help to provide a real sense of space.

HOST: Are there also economic benefits associated with using natural infrastructure?

KIM PENN: These are really important. Coastal communities are trying to weigh the costs and benefits of the resilience choices that they are making. And so the economic value of natural infrastructure comes into play as a question quite a bit. In addition to the sort of obvious economic value of some of the activities I mentioned, commercial fisheries, tourism, or recreation – these approaches can really be a cost-effective solution for mitigating against hazards. A couple of examples that I have are, one’s in Aurora, Illinois, where the city installed 28 rain gardens at intersections in the combined storm sewer area across the city. And by installing these rain gardens instead of constructing additional gray infrastructure to manage the stormwater, Aurora saved an estimated 1.8 million.

Another good example is in New York City. Through the development of their Green Infrastructure Plan, the city’s estimated that they’ll realize a savings of $1.4 billion from substituting gray infrastructure with green infrastructure for stormwater management.

And as another cost savings, recently there was a comprehensive study that showed that coastal wetlands played a really important role as the first line of defense from storm surges during Hurricane Sandy. It found that coastal wetlands prevented more than 625 million dollars in property damages from Maine to North Carolina. And in this case, even relatively degraded wetlands in urban areas of New York City and New Jersey saved communities hundreds of millions of dollars.

HOST: I heard you mention “gray infrastructure” earlier. What is that?

KIM PENN: In some places natural infrastructure by itself isn’t always enough to manage the risk of certain hazards to the level desired. So some examples of gray infrastructure are sea walls or revetments, riprap - anything that is constructed to mitigate against - in this case we’re talking about coastal hazards.

Depending on the hazard, for example erosion or storm surge, and the shoreline’s proximity to critical infrastructure – such as roadways - a natural system alone just might not be sufficient.

You may need or want to incorporate some gray infrastructure to be the most effective solution. So these kind of solutions that include both green and gray components are sometimes called hybrid approaches.

Another example are the living shorelines approaches that I mentioned earlier, where you may have a more gray component, such as an artificial reef or a stone sill. One other example, which I bet maybe everyone has seen but doesn’t know the technical term for are bioswales. So if you see a ditch on the side of the road that has a lot of plants in it, it’s likely a bioswale - they also combine green and gray, though you aren’t able to really see the gray components. Bioswales are created to absorb and clean water during rain events. So there’s usually gravel underneath the plants to help with water drainage.

HOST: Ah yes, I’ve seen those, but didn’t know what they were called. Where else might someone notice examples of natural infrastructure?

KIM PENN: Sure, everywhere. We include natural areas that have been protected or restored as natural infrastructure. So basically any time you see a beach or a dune or a wetland you’re seeing natural infrastructure.

HOST: Are scientists and coastal managers the only ones that can make use of nature-based approaches?

KIM PENN: Almost anyone can really make use of nature-based approaches.

So if you’re a coastal landowner, you can make a choice about how to protect your shoreline from erosion. In many coastal states living shorelines are becoming a protection measure of choice, actually.

And even if you don’t live along the coast, you can plant a rain garden, use permeable pavers for your driveway. Schools, such as my son’s, are also incorporating rain gardens. And even at the state level floodplain managers will opt to protect or restore floodplains at watershed scale.

Again, natural and nature-based approaches can be implemented at so many different scales, that everyone can be involved. Through your neighborhood or your schools or your community groups. Volunteers can help with planting marsh grasses, or constructing a rain garden, or maintaining bioswales – there really is a great opportunity for local and state governments and nonprofits to partner, educate, and bring communities together.

HOST: There are so many ways for people to get involved! That being said, are there any challenges you’re aware of that communities face when they start to implement natural infrastructure?

KIM PENN: Awareness is really a big one. Sometimes community decision-makers don’t know about the diversity of natural and nature-based solutions, or really understand the multiple benefits of these approaches, which can impact their decision-making.

Planners might not know where to go for the information and data necessary to incorporate natural infrastructure. So even once they choose to use a nature-based approach, how to plan for those might be encumbered.

Permitting processes might not be as straightforward for nature-based solutions, as some of these techniques are really just gaining in popularity. So in some states it actually is more difficult to permit for a living shoreline than it is for a hardened shoreline, which is a barrier for, for coastal landowners.

And even for those who are ready to construct their living shoreline or incorporate nature-based approaches for stormwater management, it can be really difficult to find engineers that are trained in designing those features.

HOST: How is NOAA helping to address these challenges?

KIM PENN: Many of our key partners, including state coastal management programs and national estuarine research reserves, study, plan for, and implement natural and nature-based infrastructure projects within communities. So we really support them both through financial and technical assistance. Examples of the technical assistance include visualization tools, training opportunities, and access to data that can be used for community planning.

I also want to say that we work really closely with our federal and non-federal partners to ensure that our efforts are coordinated and coastal management needs around natural infrastructure are addressed.

HOST: That’s fantastic. Can you share a success story from a community that’s implemented natural infrastructure?

KIM PENN: Yes. There is actually a great recent one from Hurricane Harvey in Clear Lake, Texas, where the community had reclaimed an abandoned golf course and restored it to a 200-acre urban wetland. It performed exactly how it was intended by acting as a sponge to keep floodwaters away from area homes. You can see an amazing video showing the water rising during the storm but staying within the wetland area on our webpage.

The reclaimed area is called Exploration Green and the plan for the open space includes hiking, biking, pedestrian trails, athletic fields, and native grassland areas, providing those additional benefits that we talked about earlier.

HOST: That is very cool. Can you think of any other success stories?

KIM PENN: So in North Carolina there was a study conducted before and after Hurricane Irene and it showed that living shorelines, in this case they were marshes, with and without sills were more durable and actually protected the shorelines better than those with bulkheads.

They found that over 75% of the bulkheads were actually damaged during the storm whereas no damage occurred to the living shorelines.

HOST: Where can our listeners go to learn more about natural infrastructure?

KIM PENN: Of course, I hope a lot of people go to our Digital Coast website, which is a great place to start. On the Digital Coast website you can find a link to natural infrastructure under the Topics tab, and there you’ll find the tools, trainings, quick references, and videos.

Our partners, which include your state coastal programs or national estuarine research reserves, The Trust for Public Land, The Nature Conservancy, and many others, also can provide a wealth of information to a diversity of audiences. And many of those resources can also be accessed via links from Digital Coast.

For our coastal managers, we also have a popular training opportunity that’s designed to help coastal communities understand how they can use natural infrastructure approaches to reduce impacts from hazards and adapt to changing climate conditions. These two things help to address that awareness barrier or challenge that we talked about earlier.

HOST: For our listeners, you can find the Digital Coast website that Kim mentioned at coast.noaa.gov.

Kim, before we wrap up, can you share what it’s like for you working to help coastal communities implement natural infrastructure?

KIM PENN: Yeah, absolutely. I find it extremely rewarding. Natural infrastructure and coastal resilience is really something that everyone can and should get behind. As we discussed, the benefits are diverse and they really can be enjoyed by the whole community – homeowners, children, transportation planners, and businesses. The list really goes on.

I also personally really love the partnerships aspect.

It’s been really rewarding to be able to respond to coastal management needs. Needs for information and for training, for example. And then to really see the communities we work with incorporate natural solutions, and realize the benefits on the ground.

While we talked a lot about how communities are just starting to really strategically incorporate natural infrastructure into planning specifically for coastal protection and resilience, this, this isn’t a new concept.

We’ve really known about the diversity of benefits provided by coastal ecosystems for a long time. And my hope is that we stop thinking about natural infrastructure as sort of new and different option, but really as an integral component of building a resilient community. As something that just makes common sense - environmental, social and economic sense.

HOST: That’s it for this episode of the NOAA Ocean Podcast. Thanks to Kim Penn for explaining the multi-faceted benefits of natural infrastructure, and its role in protecting our communities. And thanks to you for listening. To learn more about natural infrastructure, or any ocean-related subject, visit our website at oceanservice.noaa.gov.