Coconuts become tools for shoreline protection

NEPTUNE, NJ (AP) — Coastal communities around the world are putting a tropical twist on coastline protection thanks to the humble coconut.

From the sands of the Jersey Shore to the islands of Indonesia, bundles of coconut shells, known as coirs, have been incorporated into shoreline protection projects.

Coconut material, often used in combination with other means, is seen as a cost-effective, readily available, and sustainable option. However, the material is also popular in wealthy countries, where it is considered an important part of so-called “living coastlines” that use natural elements rather than rigid barriers of wood, iron or concrete.

One such project is located along a section of eroded riverbank in Neptune, New Jersey, about a mile from the waters of the Shark River. Using a combination of federal grants and local funding, the coastal protection group, the American Coastal Association, is implementing a $1.3 million project. The project has already significantly added to the previously heavily eroded coastline in the area hit by Superstorm Sandy. year 2012.

“We are always striving to reduce wave energy while protecting our coastlines, and we want to adopt nature-based solutions wherever possible,” said Tim Dillingham, Group Executive Director. I’m here. “This material is readily available, especially in developing countries, and is relatively inexpensive compared to harder materials.”

Coir is made of the filamentous fibers of the coconut shell, spun into mats or logs and often bundled in nets.

Its flexibility allows it to be shaped as needed, contoured over uneven areas of the shoreline and secured with wooden stakes.

Coconut-based materials, by design, biodegrade over time. But before that, you may pre-seed shoreline plants and grasses, or place them in holes where you can drive those plants into the coir log.

Logs hold plants in place as they take root and grow, eventually decomposing, leaving behind established plants and sediment around them, stabilizing the coastline.

Coconut-based materials are used worldwide for erosion control projects.

One of them is in Boston, where Julia Hopkins, an assistant professor at Northeastern University, uses coconut fibers, wood chips, and other materials to create floating mats that dampen waves and encourage aquatic plant growth. doing. A pilot project has four of her mats installed in waterways around Boston. Hopkins envisions networks of hundreds or thousands of linked mats to protect larger areas.

She is happy with what she has seen so far.

“Coconut fiber is an organic material that is relatively cheap and a waste product.

Two projects in East Providence, Rhode Island, will use coconut logs in 2020, and in 2021, the 2,400-foot (731-meter) shoreline of New York’s Jamaica Bay eroded by Superstorm Sandy will be replaced by coconut coir. Stabilized by a project containing logs.

A similar project was implemented last year in Cape Cod, Massachusetts. The Delaware Department of Natural Resources and Environmental Management provides funding to help landowners, homeowners associations, and others install living shorelines made of materials containing coconut fiber. .

A project in Austin, Texas has stabilized a portion of Lake Austin’s shoreline. Monitoring from 2009 to 2014 showed a reduction in erosion and healthy growth of riparian native plants.

Indonesia is the world’s largest coconut producer, with over 17 million tonnes in 2021. Scientists from Bandung Institute of Technology’s oceanography program used coconut shell material to help build a breakwater in Kalanjaradri village, Pangandaran province in 2018.

Residents of Diog Island in Senegal are using wooden structures and coconut leaves and sticks to fill in the eroded parts of the beach.

However, it doesn’t always work.

In 2016, the Felix Neck Wildlife Refuge on Martha’s Vineyard in Edgartown, Massachusetts, set up on Sengekontucket Pond, where salt marshes have eroded several feet. It helped mitigate erosion for a while, but the shell didn’t last long due to the strong wave action.

“It’s been blown over and over again,” said reserve director Susan Bellincampi. “We had it installed for several years, but decided not to reinstall it.

“This project was very interesting because of what we wanted to do and how we adapted it,” she said. “Doesn’t apply to all sites. Must be site specific. Works in some places. Doesn’t work in all places.”

Similarly, coconut fiber mats and logs were recently used on Chapel Island, Nova Scotia, Canada, but were damaged in severe weather.

Elsewhere in Canada, Lac des Battures, a lake on Nuns Island in Montreal, uses coconut mats to control invasive reed growth along its shoreline.

At the New Jersey site, a few miles south of music hotbed Asbury Park, trucked sand combines with tidal sediment to create a beach noticeably wider than where it once was. increase.

“You are now a hibernating fiddler crab under your feet,” said Capt. Al Modjeski, a coastal association restoration expert. “They will be thrilled with this new habitat.”


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