Nature can be a great ally for infrastructure
By Kate Layton, marketing and communications manager, and
Kaitlin Collins, watershed planning coordinator
Infrastructure is only as good as we make it. Roads, walls and levees are necessary to our modern world, but they don’t last forever. These foundations weaken over time while nature, persistently and inevitably, finds its way to the surface. Grass and tree roots can crack a sidewalk, and even daily ebbs and flows in a river can erode a rock wall at its bank.
Just a month ago, right before Hurricane Florence walloped the Carolinas, downpours in Philadelphia brought the Delaware River dangerously near to street level and made thoroughfares like Christopher Columbus Avenue look like canals. In August 2016, part of a wall along Philadelphia’s Schuylkill River failed due to erosion. Foot and bicycle traffic along the river had to be rerouted so that parts of the wall that crumbled into the water could be replaced.
Nature, in all its resilience, can be a great ally as well. Perhaps our best means of protecting infrastructure against the elements is by working with nature and not against it. Not only do nature-based solutions exist, they’re used in states around the East and Gulf coasts, including in urban areas such as Lardner’s Point Park along the Delaware River in Philadelphia. These practices address erosion, flooding and pollution by incorporating natural elements with traditional infrastructure. They provide multiple benefits and can be less expensive to maintain than outright replacing traditional infrastructure along coasts and urban waterways. Partnership for the Delaware Estuary (PDE) and partner organizations have put a nature-based method called a living shoreline to work for years. Instead of using concrete, fencing or riprap, which crumble and break apart, living shorelines use coconut fiber logs, oyster shells, and native plants that can take what nature dishes out. While a concrete sea wall is only at its strongest during its first days, living shorelines get stronger over time as grasses thicken and wildlife turns these areas into habitat. Other benefits of living shorelines are:
They’re wave buffers: As living shorelines mature, they absorb waves that would otherwise directly hit concrete walls, sidewalks or roads.
They keep junk out of the water: Shoreline grasses trap and isolate carbon, sediments and other pollutants, leaving us with cleaner waters and a healthier ecosystem.
They’re low cost: Installing and replacing concrete can be timely and expensive, whereas living shorelines can be less expensive to install and maintain.
They attract birds: Plants, animals, and birds need connections to land and water. Living shorelines provide this important connection.
They’re adaptable: Living shorelines are designed to adapt to their environment and can stand up to sea level rise in a way that rigid sea walls cannot.
PDE’s has living shorelines at the DuPont Nature Center near Milford, Delaware, at Anchor Marina in Heislerville, New Jersey, and more locations in Pennsylvania. Heislerville’s shorelines survived Hurricanes Sandy and Irene as well as tropical storm Lee while Sandy devastated most of southeastern New Jersey. PDE also has installed living shorelines in Pennsylvania, and more could be on their way. To learn more about living shorelines and about PDE, visit its website: www.delawareestuary.org.