Presented at NOAA Coastal GeoTools 2011 - This paper describes the use of remote sensing data, GIS habitat mapping, and environmental sensitivity analysis methods to map selected coastal and seafloor features. These technologies are employed to develop an efficient means of determining and mapping nearshore and seafloor features warranting environmental protection. The application of remote sensing techniques to high-resolution aerial or satellite imagery may be utilized to identify and delineate near-shore and coastal features and perform habitat classifications. These data can be used to produce Environmental Sensitivity Index (ESI) maps, thematic maps, and statistical summaries (areal and linear dimensions) of habitat type which may support Environmental Impact Assessments (EIAs), Environmental Impact Studies (EISs), Baseline Environmental Baseline Surveys (EBSs), monitoring plans, and spill contingency planning. This rapid assessment and mapping approach gives a time-efficient and cost-effective means to identify and map environmentally sensitive features within a large and environmentally complex geographical area. This paper additionally presents the development and application of an environmental impact mitigation plan based on a combination of the ESI analysis and habitat mapping data. This combined technical approach is a practical means to minimize environmental impact while meeting the scientific, engineering and logistic constraints of coastal and marine development activities.

1. Imagery Interpretation for
Coastal and Marine Spatial Planning
Prepared for:
2011 NOAA GeoTools
Keith B. VanGraafeiland
Stephen T. Viada
M. John Thompson
Brian Balcom
George McLeod

2. Acknowledgments
Anadarko Petroleum Corporation (APC)
• John Peffer
• Mario Rassul
• Karina Pena

3. Purpose
• Remote Sensing Data
– Satellite imagery
– Side-scan sonar
• GIS Habitat Mapping
– Imagery classification
– Imagery interpretation
• Environmental Sensitivity Analysis Methods
– Identify features and areas of concern for
avoidance and to minimize environmental impacts

4. • Produce
– Environmental Sensitivity Index (ESI) maps
– Thematic maps
– Statistical summaries (areal and linear
dimensions) of habitat type
• Support
– Environmental Impact Assessments (EIAs)
– Environmental Impact Studies (EISs)
– Environmental Baseline Surveys (EBSs)
– Monitoring plans
– Spill contingency plans
Purpose (Cont.)

5. Case Study
Northern Mozambique, Africa
• A 2D and 3D geophysical
survey program proposed
within shallow waters of the
Quirimbas Archipelago,
Mozambique
Study purpose
• Locate seafloor features
warranting environmental
protection from seismic
operations
• Develop a mitigation plan to
minimize potential
environmental impacts

6. Study Objectives
1. Characterize and map marine habitats
2. Identify physical areas of concern
3. Develop a mitigation plan
4. Implement a field survey to delineate
areas of environmental concern
Deliverables
• EIA, with an approved environmental
impact mitigation plan
• Environmental Management Plan (EMP)

7. • Mangrove-dominated communities
• Submerged aquatic vegetation
• Bare sand and mud substrates
• Shallow and emergent hard substrates
• Shallow and emergent coral
communities
• Deepwater coral communities
Objective 1:
Characterization and Mapping of
Shallow Water Marine Habitats

8. • A set of high resolution remote sensing
(satellite imagery) tiles of the coastal and
nearshore waters of the project area were
used to create a georeferenced mosaic
• Habitat categories were identified and coded
as colored polygons, creating a
georeferenced habitat map
Objective 1 (Cont.)

9. • ESI methods were used to
determine the relative
sensitivity of each identified
habitat category
• Sources of environmental
impact
– Seismic sound pressure waves
– Physical contact with receiver
cables and autonomous
receivers
Objective 2:
Habitat Sensitivity Analysis

10. Potential Levels of Impact Severity
Impact Severity Consequence
Negligible
Negligible or little harm to sensitive resources, with reversible effects
Little or no environmental exposure
Minor
Low, minor environmental impact
Exposure limited to immediate site
Moderate
Medium, moderate environmental impact
Incident potentially contaminating local resources
Significant
Major environmental impact (see text below)
Environmental incident resulting in contamination of local resources
Catastrophic
Catastrophic disaster, major environmental impact
Major environmental incident causing significant regional damage to the environment
Scale of Environmental Sensitivity
1
Negligible
2
Minor
3
Moderate
4
Significant
5
Catastrophic
Severity of Impact
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11. Objective 3:
Develop a Mitigation Plan for the Protection
of the Identified Areas of Concern
• From the ESI results, an impact
mitigation strategy was designed
to avoid or minimize potential
impacts to sensitive marine
resources and habitats
• Mitigation measures consisted of
acoustic exclusion zones
(“buffer zones”), considering
proposed activity scenarios

12. Objective 4:
Field Survey
• A field survey was designed and implemented
to accurately and efficiently identify and
delineate areas that met sensitive habitat
criteria

13. Field Survey Methods
• Preliminary mapping survey of selected
segments with digital side-scan sonar
• Visual assessment (groundtruthing) of selected
seafloor features by divers

14. Survey Data Analysis
The processed sonar
data swath was
superimposed on the
satellite mosaic for
interpretation
Each proposed
seismic survey
trackline was
superimposed on
the corresponding
satellite mosaic

15. Survey Data Analysis (Cont.)
Results obtained
from
groundtruthing
selected targets
provided
supportive
information for
seafloor
interpretation
Selected
groundtruth targets
were plotted, and
areas meeting
selection criteria
were provided a
buffer of 75 m
The final product
comprised a
color-coded
overlay of the
surveyed trackline
segment

16. Survey Results
• 250 km were surveyed
• 90 km were in water depths <2 m
• 42 km were designated as sensitive habitat
• 118 km did not contain sensitive habitat or
were too deep to survey

17. Conclusions
• Sensitive shallow water habitats
were mapped within the project
area
• Acoustic exclusion areas
(buffers) for selected resources
were implemented
• The methods provide a practical
and efficient means to
characterize and map seafloor
habitats within large geographic
areas and may be applied to
other activity scenarios and
geographic areas