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

such as number of flood events at a community or reported flood damages, are documented
evidence of flood risk. On the other hand, some parameters, such as watershed deforestation or
dominant soil hydrologic soil class, attempt to quantify the potential for community flood risk.
This concept is important to consider in applying the parameters in the prioritization process.
The application of this concept led to the distinction between parameters outlined in Table 4-7.
All seven first order parameters, as well as all of the second order parameters, were applied for
those communities where flood plain mapping is presently available. The first order parameters
were applied for sorting of communities in the order presented in Table 4-7. The summation of
the second order parameters was used for ranking.
First order parameters #2, #3, #4 and #6 and all of the second order parameters were applied
for prioritization of communities which do not presently have flood plain mapping. The First
order parameters noted above were applied for sorting of communities in the order presented in
Table 4-7. Similar to above, the summation of the second order parameters was used for
ranking.
The decision matrix was developed in such a way that allows for options assessment. That is,
varying the application of the parameters to yield alternate prioritization patterns.
The application of the prioritization data and methods described above yields the following
ranking of communities; for communities with flood plain mapping presently (see Table 4-8) and
for communities (the first twenty) without flood plain mapping presently (see Table 4-9). The
complete prioritization list of communities without flood plain mapping is provided in Appendix A
- Prioritization of Communities for New Flood Plain Mapping.
As can be seen in Table 4-9, St. John‟s is identified as a priority community for new flood plain
mapping. This is primarily due to the number of recorded flood events recorded for St. John‟s
LGP number in the Flood Events Inventory. It is clear that the municipality of St. John‟s covers a
large area and numerous smaller communities exist within St. John‟s, some of which already
have flood plain mapping. The prioritization data and methods employed for this study are not
suited to review of individual unique areas within a municipality, only the municipality as a
whole. In order to prioritize individual areas within the municipality of St. John‟s for new flood
plain mapping, a review of individual flood circumstances should be initiated by WRMD.
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