The Sugarloaf Island Restoration Project, coordinated by a public–private partnership in Morehead City, North Carolina, is working to stabilize a small barrier island that serves as a natural buffer against storms. Beginning in 2023, nature-based shoreline structures—including the WAD® system (Living Shoreline Solutions Inc) and oyster breakwaters constructed using Oyster Catcher™ substrates (Sandbar Oyster Company)—were installed to reduce erosion and enhance sediment retention.
Our lab leads the drone-based monitoring program, conducting repeated surveys to measure shoreline change before, during, and after stabilization. These high-resolution observations help evaluate how nature-based solutions perform across seasonal cycles and storm events.
Research Questions
- How does the shoreline respond to storms, seasonal cycles, and the installation of hybrid living shoreline structures?
- What physical changes occur around Wave Attenuation Devices and oyster breakwaters?
- Can repeated drone surveys capture these shifts with enough precision to detect meaningful change?
Methods
We conduct seasonal drone surveys to measure how Sugarloaf Island’s shoreline evolves before and after the installation of hybrid living shoreline structures. Each survey uses small uncrewed aerial systems (sUAS) and Structure-from-Motion (SfM) photogrammetry, supported by RTK-GNSS control for sub-decimeter accuracy. The resulting 3D models and orthomosaics capture fine-scale changes in elevation and sediment movement, allowing us to quantify shoreline response through time.
Key Findings (so far)
- Pre-stabilization: Surveys captured storm-driven erosion from Tropical Storm Ophelia (2023) and a December 2023 nor’easter.
- During stabilization: Initial oyster reef and WAD placements coincided with localized accretion on the west spit.
- Post-stabilization: By summer–fall 2024, surveys showed higher rates of accretion, suggesting that the nature-based structures enhanced sediment retention.
Why It Matters
Sugarloaf Island provides a rare full-cycle case study: pre-, during-, and post-stabilization monitoring. By combining repeated drone-based mapping with precision-bounded change detection, we are evaluating how nature-based shoreline protection performs under seasonal cycles and storm events. This work helps identify where these approaches succeed, where they face limits, and how results can guide future coastal resilience planning.
Publications & Data
- NEW! Pettyjohn, S., Sirianni, H., Sirianni, M.J. et al. Seasonally structured drone data for shoreline change around a hybrid living shoreline project. Scientific Data (2025). https://doi.org/10.1038/s41597-025-06310-z
- Drone Datasets: The full seasonal drone mapping dataset for Sugarloaf Island (2023–2025) is publicly available through Figshare with DOI-linked records.
https://doi.org/10.25452/figshare.plus.c.8101450 - Drone Metadata Template & Structure (Reusable Resource):
Pettyjohn, S., Sirianni, H., Sirianni, M.J., Burchi, B., & Gittman, R.K. (2025). Drone Mapping Dataset – Seasonal Structure & Metadata Template – RTK-GNSS & SfM – Sugarloaf Island, NC. Figshare+. Dataset.
https://doi.org/10.25452/figshare.plus.29649509.v1
Support & Acknowledgements
Our Sugarloaf Island monitoring is supported by the North Carolina Coastal Federation, in collaboration with the Town of Morehead City and the Sugarloaf Island technical team. Field operations relied on the NC Continuously Operating Reference Station (CORS) network for geospatial control and accuracy.
