Green Infrastructure for Coastal Resiliency Focus of Conference

By PAT JOHNSON | Nov 18, 2015
Photo by: Pat Johnson Planners and municipal officials gathered at the Jacques Cousteau Estaurine  Research Reserve in Tuckerton to learn about creating green flood resiliency projects and storm water management techniques.

Since Superstorm Sandy, the most popular buzz-words among planners and municipal officials are “resiliency” and “green infrastructure,” said Lisa Auermuller as she opened a Nov. 17 conference focused on those very words, held at the Jacque Cousteau Estuarine Research Reserve Education Center in Tuckerton. Planners, officials and concerned citizens from as far away as Staten Island and as close as Tuckerton came, hoping to “make a better world, even if global warming is a hoax,” to paraphrase a popular joke.

Green infrastructure can be many things. It can be creating green spaces, new storm water practices and rules, building a rain garden, collecting water in a rain barrel or mitigating wetlands and shorelines with oyster reefs or coconut-fiber wave barriers.

Lauren Long from the National Oceanic and Atmospheric Administration said flood-resiliency projects are best when they are made with natural materials and far more affordable than hard structures.

Danielle Kreeger from the Partnership for the Delaware Estuary has had real-life experience with creating natural shorelines along the Delaware out of “coir logs” made from coconut tree fiber that are staked in front of eroding wetlands and with making oyster reef barriers. Both attenuate or calm wave action and also increase habitat for other crustaceans, including blue claw crabs, which are the main fishing industry of the bay.

Kreeger had some sobering news for the public: The Delaware River basin is experiencing massive loss of natural habitats. In 10 years, 40 square miles of forests have disappeared (between 1996 to 2006) and we are still losing about an acre a day of tidal wetlands. And this is a estuary where coastal wetlands from a  continuous band on both sides of the river and bay from Cape May to Camden.

A reason that may not come readily to mind is sea level rise. In the early 1900s, sea level rise was 2 millimeters per year; the wetlands were able to keep up with that by accretion, or the build-up from natural detritus and captured sediment. “Now we are at 4 millimeters and many can’t keep up. At 8 to 10 millimeters, most wetlands will be drowned and become open water.”

It’s not just the recreational public or the wildlife that lose out. For those who must think in terms of money, the states are losing dollars as well.

“The New Jersey DEP did a study to find how much our natural green infrastructure is worth, and the most valuable habitat is coastal wetlands,” said Kreeger.

“The challenge is significant, but the good news is with green infrastructure we have a fighting chance. We have the technology now and we know how to do it, whether it be sediment application called thin layer deposition or oyster reefs instead of a seawall or bulkhead.”

But once the green infrastructure is built, it must be maintained. “You need to tend your garden or it will disappear,” she said.

Kreeger showed slides of a project in Heislerville on the Delaware near where a crab-shedding concern was located. “They had thrown everything along the shore to keep it from eroding – rip rap, concrete waste, you name it – and we came along with our natural infrastructure, our coir logs, and planted them with grass and mussels, and it works. Hard structures deflect wave action and eventually erode from behind, but natural infrastructure dissipates wave energy. Even the Army Corps of Engineers studied the difference between gray structures (hard) and natural ones, and the living shorelines did better.”

Because grant money is precious, she suggested planners study their communities and find areas where the coastal loss is most distressing to the population. “Maybe it’s a wetland along a road or another feature. Talk to local people; they’ll tell you. And then make a map of vulnerability where the losses are taking place the quickest.”

Besides sea level rise, another practice that is damaging the salt marshes is the practice of mosquito ditching called “open marsh water management,” which fragments the land and allows more water to drown the marsh.

“It turns the marsh into Swiss cheese, but the various county mosquito commissions seem to trump everyone,” said Kreeger. “I don’t know why except that they want to keep the mosquitoes low for the tourists.”

And phragmites eradication seems to make no sense, said a participant, when the common reeds have root systems that hold the edges of marshes in place.

“The state has been anti-phragmites and has been dumping herbicides on it for 10 to 20 years hoping to eradicate it to create better habitat for fish and wildlife,” Kreeger said. “That again points out that what you are managing the resource for makes your priorities different.”

Last but not the least of the problems facing saltwater marshes is nutrient loading from fertilizer runoff.

“Saltwater marshes are nutrient poor. You look at a wetland, and the plants that are growing there have adapted to spread out deep roots to gather every bit of nutrient they can. Now they are fertilized from runoff and the foliage becomes lush and beautiful, but the root systems are impaired and shallow. Right before a marsh dies, it looks lush.”

Chris Obropta from Rutgers University’s Water Resources Program and the Rutgers Cooperative Extension discussed green infrastructure in the urban landscape. He said it was his job to help people solve problems as cheaply as possible.

“We need to put green infrastructure everywhere and do it now. Regulations can control some of the future development with regulations if the towns enforce them, but we’re in trouble, and we have flooding now.”

A project that he worked on for East Brunswick served as his lecture model. “We looked at their community and found that 23 percent of their landmass was impervious coverage,” said Obropta. “At 10 percent you start to have problems with storm water, and at 25 percent you have degraded your waterways – they are just storm water catch basins.

“So I scared them by showing them how much storm water they generated from an inch and a half of rain, and it was 112.1 million gallons of water. They looked at their water bottles and thought, ‘Wow, that’s a lot of water.’”

Obropta did a survey of where that impervious coverage was and took pictures of schools, churches and municipal buildings that have a lot of roofs and parking lots. Out of 20 or 30 sites, they choose three to work on, “as nobody has any money,” he said.

“I love working on schools because they have a lot of students who can build rain gardens and are a great labor opportunity. Churches are good because ‘God wants us to look after the planet,’ and municipal buildings are good because they can use their public works (departments) to do the jobs.

“Rain barrels are a good way to start; they are like the gateway drugs to bio-retention. The wife goes to a community function and makes the barrel and gets her hubby to install it and cut the roof downspout off. Now, it will only handle 55 gallons and fills up right away, but I’ve got them to disconnect their downspout. Now instead of running out the driveway to the storm drain, the overflow runs across the lawn and infiltrates. And the couple feel like they are saving the planet and start to look for other green projects.”

Obropta also suggested another good community project is to create a green car wash. “All community volunteer organizations use car washes to raise money, so why not create a green car wash where the water comes from a collective cistern and runs off into rain gardens? Rain gardens take out 90 percent of the suds.”

Philadelphia and Portland, Ore., are using bio-swales along roadways that are concrete planters that storm water gets directed into as it runs along the gutter. The plants help absorb the pollution.

“The best way to manage impervious coverage is to store the water right underneath it,” Obropta said. “I like porous asphalt the best. I get a call every time it rains from a guy in East Brunswick who can’t believe the basketball court is dry after a rain. The other good thing about porous asphalt is it doesn’t create black ice. So your mother-in-law crossing the parking lot doesn’t break her hip and move in with you and impact your lifestyle.”

Jokes aside, Obropta said there is money available from Sea Grant to improve storm water management in communities that have a blueprint for projects. “And NJDEP likes to fund projects that are already in the works.

“Someday we are going to have storm water utilities and utility fees,” he predicted.

Amy Williams from the Stevens Institute of Technology, vice president of the Alliance for a Living Ocean based on Long Beach Island, spoke to the group about work she had done with the Hudson River Sustainable Shorelines program: creating “rock-sills,” a series of planted terraces bordered by rocks; gambian baskets that let tidal water flow through to pools for public access along the river. A 1.9-mile beach nourishment project in lower Cape May included dunes and beach fill plus a series of levees that withstood Sandy-generated waves. “It cost $15 million but recouped $9.6 million in flood damage reduction, and an increase in eco-tourism.”

Conference participants were encouraged to incorporate green infrastructure projects into their master plans and hazard mitigation plans.

patjohnson@thesandpaper.net

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