On September 18th, 2003 a massive breach isolated more than 300 permanent residents of Hatteras Island when Hurricane Isabel carried a destructive storm surge and 100 mph winds to the North Carolina coast. The damage brought travel along Hatteras Island to a halt. Named Izzy’s inlet by residents, planning began immediately to fill the 1700 foot wide, 26 foot deep breach between Hatteras Village and Frisco.
Izzy’s Inlet was filled through a joint effort between the US Army Corps of Engineers (USACOE), FEMA, North Carolina Department of Transportation (NCDOT), USFWS, NCDENR, Coastal Area Management Service, and the National Parks Service. Less than a month after the storm dredging operations began pumping sand and water from the Ocracoke-Hatteras ferry channel in Pamlico Sound to the newly formed inlet. Within two months the island was reconnected and the torn apart stretch of highway 12 was rebuilt.
In the spring of 2006, three years after the fill, the rebuilt stretch of land was slow in recovery. “It was this lunar landscape,” describes Zac Long, an ecologist with the University of North Carolina’s Institute of Marine Sciences. A first analysis made by Long and Charles “Pete” Peterson, director of the research effort and marine sciences professor, showed the ocean side seemed to be recovering on its own, while the sound side sand was hard and terrestrial plant communities were desolate. These were early signs that ecological systems were not restoring to normal within a reasonable timeframe.
A project was hatched by the University Of North Carolina Institute Of Marine Sciences (UNC – IMS) in Morehead City and the UNC Coastal Studies Institute (UNC – CSI) in Manteo to research the recovery and restoration of ecological communities on the Izzy’s inlet plug. Their goal was to monitor the time course of recovery of biotic communities of the three affected habitats on the plug; the intertidal-shallow subtidal beach, the dune field and the intertidal–supratidal estuarine shoreline. Within these three habitats researchers monitored the time course of use by vertebrates, especially birds, and documented the physical characteristics and critical processes in order to characterize changing levels of risk of future injury. Through interaction with the National Parks Service, research began to assess damage and determine the need for “overt restoration efforts” that would enhance recovery. Original conclusions, made by Peterson and Long, that “ocean benthic communities have recovered, while the dune and marsh plant communities and marsh benthic communities have not” held true during ongoing research over the 2006/2007 winter.
Peterson and Long engaged in two experiments; the second experiment centered on the sound side where restoration efforts previously lacked. When filling Izzy’s Inlet, restoration was done on the beach dune where sea oats were planted but any sound side restoration lacked. In an ongoing plant experiment focused on the sound side, Long suggests planting ample and diverse species to hopefully aid in recovery of damaged systems. “Three species were planted in monoculture under different combinations of fertilizer and organic material (peat),” describes Long. After seeing the differing responses of the species to the fertilizer and organic material Long suggests, “That more diverse plant communities will more efficiently utilize the habitat. An effective way to quickly increase plant standing stock biomass and quickly recover or restore the system would be to plant as many (plant) species as possible.”
The filling of the breach provided a unique opportunity to develop an understanding of natural recovery and resiliency of the ecological communities from ocean to sound and assess if unnatural environmental conditions limit recovery. According to Long, “this environment (the Outer Banks) is harsh because of low soil nutrients, low soil moisture, high salinity, high light levels and wind stress.” The plant experiment provides insight to possible remedies and preventative measures to these harsh conditions. One recommendation this study suggests is that future restoration efforts of maritime communities should focus first on the restoring diverse plant communities on the marsh and the ocean side communities second. Salt marsh restoration in the fill area would likely be more successful then other restoration techniques because of elevation levels available. Another recommendation suggested by this research is that storm erosion may be repelled by planting these studied combinations of plant species whose roots bind together. Because of steep shoreline and deep water near the shore, the fill area is susceptible to future erosion caused by storm events.
Another aspect of this experiment studied the most effective way to restore a fill area by using various planting strategies. This study showed that a fertilized mixture of plants species was a more effective way to accelerate the recovery of plant production and cover, while monocultures of sea oats will promote the establishment of other species since the dense grasses can trap seeds and ameliorate the harsh abiotic conditions. Dune habitat restoration might best use monocultures of sea oats, while fertilized mixtures might be used in the shrub zone to better match the natural plant composition of barrier island habitats.
Looking toward the future, the possibility of major damage to barrier islands and the need for restoration efforts is very likely. Peterson stated that due to global warming and increased storm intensity, geological time is at full speed “It’s important to see what these consequences are now,” said Peterson. Here is the opportunity to gain an understanding of how to respond appropriately to these events in the future by determining ecologically friendly actions that can enhance damaged ecosystems.