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<br />be inundated and surface wave action may occur. A structure located where it is subject to high
<br />velocity flow would be more appropriately moved than protected. Properly protected, a
<br />structure should not incur excessive damage if that protection level is exceeded.
<br />
<br />Some nonstructural measures require warning time to implement: for example, flood shields
<br />for doorways and windows, and gates for openings in walls or levees, or evacuation of people
<br />and property. The reliability of protection provided by measures which requ'ire warning is
<br />obviously less than for those which require no warning. in fact, it may mean the difference
<br />between protection and no protection. Once again the key to wise use of such measures is to
<br />use them where the risk of their not being in-place is minimized. This could be in situations
<br />where there is normally ample warning, where the damage incurred is small, or where the
<br />measure is the best alternative available.
<br />
<br />This discussion on degree of protection suggests that the traditional concept of providing a
<br />uniform, minimum protection for all structures is not appropriate with nonstructurai measures.
<br />Rather, protection performance should consider damage reduced, risk, consequences of the
<br />protection being exceeded, cost, and the most likely alternative. Movement away from the
<br />traditional concept would seem to enhance the ability to formuiate viable, implementable
<br />nonstructural plans.
<br />
<br />Implementation
<br />In different communities across the country there are examples where each of the
<br />nonstructural measures discussed in this report have been implemented. These measures are
<br />not new and untried. Most measures in fact have been used for decades; some for centuries. It
<br />is not that the measures themselves are new, nor that they haven't been used before, rather it's
<br />that, in the past, they have not been considered as a viable planning alternative or
<br />recommended for implementation by most planning bodies. Consequently they are "new" to
<br />most water resource planners. Also, their individual nature and low capital cost has not attracted
<br />the same attention as large scale, high capital cost projects. The amount of research has been
<br />small, the number of publications few, and our knowledge weak. However, many communities
<br />and individuals, sometimes acting out of wisdom and other times out of necessity, have used
<br />these measures to reduce the danger of flooding and the potential flood damage. It was not the
<br />purpose of this investigation to identify examples of implementation, however, during the
<br />investigation numerous examples were found. Some of these are mentioned below. Where
<br />possible a written reference is cited.
<br />
<br />Temporary and Permanent Closures for Openings in Existing Structures - Examples in LaGrange,
<br />Illinois, and Pittsburgh, Pennsylvania, are cited in Sheaffer's early work (3). Other examples are
<br />near Atlanta, Georgia, and in Prairie du Chien, Wisconsin, where an industrial building was
<br />flood proofed, although these have not been published.
<br />
<br />Raising Existing Struclures - A detailed example of one existing structure which was raised along
<br />Peach Tree Creek, Georgia, is described in Reference 5. Additional examples can be found in
<br />Wayne Township, New Jersey, and New Orleans (Southeast), Louisiana. Descriptions of these
<br />raisings have not been published.
<br />
<br />Small Walls or Levees Around New or Existing Structures - Examples of the implementation of
<br />this measure are described in Reference 4. These examples are in the Peach Tree Creek Basin
<br />near Atlanta, Georgia.
<br />
<br />9
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