N.C. considers hemp sand bags

Posted on Tue, Aug. 07, 2007

COASTAL RESOURCES COMMISSION


N.C. considers hemp sand bags

Hemp among materials that could help state's sacks of sand fade away


GARETH MCGRATH
(Wilmington) Star-News


As the N.C. Coastal Resources Commission wrestles with what to do about the proliferation of sandbags along the state's coastline, one idea that's been floated is to make the bags biodegradable.

And one of the materials under consideration is hemp -- the industrial, nonhallucinogenic cousin of marijuana.

In short, that would be one way to make sure the sandbags get rolled up instead of becoming semi-permanent structures along the N.C. coast.

"If we did adopt this, we'd be dictating the temporary nature of the bags by making them biodegradable," said Courtney Hackney, CRC chair and a marine biologist at UNC Wilmington.

The CRC has placed a May 2008 deadline for the removal of most uncovered sandbags along the coast.

Sandbags were originally meant to offer threatened structures temporary protection, generally for two years, until a more permanent solution could be developed.

Those final solutions usually were removal of the threatened property or a beach nourishment project.

But regulators have been prone to issue extensions, and many towns have successfully argued that they are pursuing a beach nourishment project to fix their erosion problem.

The Riggings condominium project in Kure Beach near Wilmington, for example, has relied on sandbags for protection since 1985.

The N.C. Division of Coastal Management recently ordered the bags removed, a decision the homeowners are challenging in court.

The bags also have proliferated in many places, forming unattractive and long, "hardened structures," since sandbags don't solve erosion but simply force it elsewhere along the beachfront. Thus, it's often only a matter of time before neighbors of a sandbagged property need the bags themselves for protection.

If the schedule remains, homeowners relying on uncovered sandbags to fend off the encroaching Atlantic could start getting removal letters in the mail next spring.

State regulators estimate there are about 150 sandbag structures that would need to come out, including 19 in New Hanover County, almost all located on Figure Eight Island.

The unknowns

Whether public pressure or the N.C. General Assembly allows state Coastal Management to go ahead with the plan is a very large unknown.

Renee Cahoon, a CRC member and mayor of Nags Head, where many of the visible sandbag structures are located, said the impending deadline is already causing consternation in her town.

"It's not going to be fun," she said.

That's led CRC members to discuss a new approach to limiting the time future sandbags can stay on the beach, which also could prompt more urgency in developing a long-term solution.

One possibility would be to use natural materials like cotton or burlap for the bags instead of polypropylene or polyester.

Those fabrics have long life spans. But the polyester fabrics often soil marshes and other coastal areas when bags are ripped or wash away.

Using natural fibers would bring a built-in time limit to a sandbag structure. It also would solve the lingering problem of "orphaned" sandbags that are left behind on the beach, whether on purpose or because they're buried.

But one of the great unknowns is how cotton or woven natural fibers, like flax or hemp, would hold up in the harsh oceanfront environment.

Natural fibers can decay quickly if not treated and could be prone to attacks by microorganisms.

Coastal Management's Scott Geiss said the initial reports aren't good, with 66 days a worst-case scenario given by industry officials.

But a 2005 Army Corps of Engineers study, prompted by the failure of sandbags in Iraq, showed cotton and burlap bags kept their strength well in a desert environment.

A dry desert, though hot and sunny like beach areas, is a much more controlled environment than the salty and wet oceanfront.

"There are a lot of unknowns out there right now," Geiss said of the practicality of using biodegradable sandbags.

http://www.charlotte.com/breaking_news/story/226709.html