Mapping Coastal Hazards
Mapping Coastal Hazards
Littoral zones of coastal waterways are dynamic environments that undergo frequent bathymetric change, induce movement of underwater objects, and scour underwater infrastructure. Furthermore, bathymetric change diverts and focuses wave energy in complex ways that effect beach and dune erosion. These changes represent hazards to navigation, beach ingress/egress, and underwater infrastructure.
The shallowness of the near-shore environment exacerbates these issues and creates difficult conditions for measuring and detecting change. Many sensor technologies require submergence in water, and shallow water creates unique challenges in performance, access, navigation, deployment, viewing, and sensor standoff distance. Risk to equipment and personnel are also a factor due to changing bottom topography, unknown obstructions, and dangerous shore conditions.
ASTRALiTe has demonstrated the ability to perform surveys of coastal areas with a high degree of accuracy, discerning navigation channels, identifying submerged objects of interest (rocks, sand bars, infrastructure, etc.), and providing accurate measurements of depth. ASTRALiTe personnel were able to scout the location, develop flight plans, perform UAV flights that simultaneously collected topographic and bathymetric data, and evaluate the resulting data in near real-time. Obtaining results while still deployed enables full data acquisition of the area of interest, and represents a huge improvement in providing access to these challenging waters.
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3m
7m
Submerged Jetty
Dune w/ Grass
Shoreline
Wake Break Jetty & Pole
Submerged Jetty
ASTRALiTe’s topographic / bathymetric LiDAR has been used to accurately measure shallow water depths, identify the extent, shape, and depth of coral formations, sand bars, and jetties. The ability to identify submerged rocks near the water surface of the Panama City Beach, FL jetty damaged in Hurricane Michael (Cat 5, Oct 2018) is a prime example of the hazards to shipping channel navigation and danger to people and boats.
Further, the LiDAR was able to locate underwater infrastructure, with centimeter-level accuracy and detail that allows objects to be identified by shape, and for infrastructure to be assessed for structural integrity / potential damage. This level of accuracy could also be used to identify suspended subsurface hazards in deeper waters like mines or debris.
