Flood Risk and Vulnerability Analysis Project - Atlantic Climate ...

source of flood vulnerabilities common to Newfoundland communities, three linked factors
emerge that are important for communities to understand in order to set priorities and establish
goals.
Watershed characteristics include those physical attributes of a watershed, both
natural and man-made that affects the flow of water through a stream system.
Characteristics include land use and associated impervious cover, topography, soil
characteristics, and stream system complexity.
Climate effects include the general trends of precipitation amounts, precipitation
frequency, snow-melt events, storm events, and tidal activity that helped shape stream
networks and impact coastal areas.
Socio-economic conditions are those factors such as population density, land
development patterns, infrastructure and property investments, and social equity issues,
which guide policies and become the basis for setting priorities.
6.1.1 Newfoundland Regions and Sub-regions
As shown in Figure 2-1, the Department of Environment and Conservation, Water Resources
Management Division divides Newfoundland into three regions. These three regions enable a
better understanding of the watershed characteristics and climatic effects across the island. As
described earlier in this report, the Eastern Region is the most susceptible to hurricanes and the
Western Region‟s stream network experiences higher volume runoff events, as a result of
spring snow-melt events.
The intent of this section is to offer high-level guidance for Newfoundland communities, related
to their decisions for adopting flood mitigation strategies that are intended to address the three
linked factors presented above. The three Regions were divided into 11 smaller Sub-regions,
based on their general physiographic composition (i.e., coastal and inland). To enable additional
analysis, Sub-regions surrounding the more intensely developed areas around Corner Brook
and the urbanized areas near St. John‟s were created. Sub-regions are presented inFigure 6-1.
The Digital Elevation Model of Newfoundland (seeFigure 6-2) that shows island topography was
also used to help define the Sub-regions. These Sub-regions were then utilized to assess
potential flood vulnerabilities.
Further subdivision could take into account additional details related to other factors that affect
flooding (e.g., soil types, forest age, impervious cover, storm surge); however, these eleven
Sub-regions provide an appropriate level of detail, based upon the scope of this evaluation and
available data, to initiate flood mitigation strategy discussions at both the Provincial and local
level. Appendix B Sub-region Communities presents a complete listing of the communities
included in each Sub-region.
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