Sunday, August 11, 2013

Sand Quarries Replenish Local Beaches

Charlestown sand helps Narragansett beaches
By CAMRYN RABIDEAU/ecoRI.org News contributor

NARRAGANSETT — Tourist season revolves around the beach, prompting the town to rely on sand replenishment as an expensive but necessary action after Hurricane Sandy's damaging visit last October.

Narragansett Town Beach required about 300 truckloads to deliver more than 6,000 cubic yards of sand to replace shoreline washed away by last year's storm. According to town engineer Jeffry Ceasrine, the town paid $167,720 for the beach sand, $42,000 for dune sand and $40,000 for beach grass.

The sand used to replenish Narragansett Beach isn't from the coastal environment but rather an inland quarry in Charlestown. The quarry is one of several in South County where sand is scooped from natural sand “banks” or deposits lying at or just below the surface. EDITOR’S NOTE: EcoRI doesn’t know which Charlestown quarry supplied the sand.



“What’s most important is that the material is classified as sand rather than silt or gravel,” Ceasrine said. Narragansett Beach needed sand as close in size, shape and color as to what it had originally, he said. To this end, the town had the existing beach sand analyzed.

David Prescott, South County Coastkeeper for Save The Bay, said that without the right grain size and shape, the sand is likely to be washed away again.

Replenishments, however, aren’t the only option for helping preserve a beach environment, Prescott said. “In areas that are less developed, the best option is to allow the beach to do what it wants to do," he said. Non-tourist destinations in South County do fine on their own, such as Black Point, East Beach in Charlestown and Quonochontaug Beach in Westerly, according to Prescott.

None of Rhode Island’s seven state-run beaches bring in sand, including those badly damaged by Sandy, such as East Matunuck in South Kingstown and Scarborough in Westerly. No beaches in Rhode Island’s have established nourishment programs, as well. Narragansett Beach typically trucks in much small amounts of sand annually for beach maintenance. 

Westerly is considering large-scale beach replacement to address its persistent beach erosion. After Hurricane Sandy, Misquamicut Beach underwent beach construction by the U.S. Army Corps of Engineers. 

In what Ceasrine describes as a fortuitous event, the town had Narragansett Beach surveyed by the engineering firm Woods Hole Group one year before Sandy hit. A profile of the beach was drawn up as part of research for a future replenishment. Little did they know they would need it so soon. 

The pre-storm surveys, combined with more surveys done after Sandy, determined where to place stakes and grade markers on the beach. These markers signified how much sand was needed to recreate the pre-storm beach elevations. The sand was then trucked in and spread using front-end loaders.

While sand from quarries is plentiful, dune grass is in short supply. Due to the overwhelming demand for dune grass on the East Coast after Sandy, the dunes at Narragansett Beach will not be replanted until this fall.

The permitting process for the Narragansett Beach project began soon after the hurricane. The new sand started arriving in May and replenishment was completed shortly before Memorial Day.

Beaches, however, are dynamic systems, and replenishments may only serve as a temporary fix. According to Prescott, another big storm could wash away the imported sand. Finding sand suitable for the beach was crucial to the success of the replenishment.

Sand from a beach environment is preferable for replenishments because it's the appropriate size and free of toxins. However, natural coastal sand is a finite resource, as it can be lost offshore or in breachways. Maintenance to recover lost sand from breachways is another expensive option for towns.


Yet coastal towns across southern Rhode Island such as Narragansett readily admit beaches are an important part of the economy, even if their upkeep can be expensive.