Currently, levees in the United States have not been catalogued, nor is there a uniform method for assessing them. Why might this be? Solution Levees and floodwalls, hereafter referred to as levees, have been part of flood management in the United States since the late 1700s because they are relatively easy to build and a reasonable infrastructure investment. A levee is a “man-made structure, usually an earthen embankment, designed and constructed in accordance with sound engineering practices to contain, control, or divert the flow of water so as to provide protection from temporary flooding. A levee system is a “flood protection system which consists of a levee, or levees, and associated structures, such as closure and drainage devices, which are constructed and operated in accordance with sound engineering practices.” Under NFIP regulations, homes and commercial buildings located in the SFHA within a participating community may be exempted from the MPR and land-use regulations when located behind a levee system that has been recognized by FEMA as providing protection against the one percent annual chance flood. The National Inventory of Dams (NID) hazard classification system is broad, qualitative, and based on the potential threat to life and property in the event of dam failure. A dam is given a \"high\" hazard rating if its failure can result in fatalities, whether the dam is small or large and has the potential for a single or thousands of fatalities. The rating is also regardless of its condition (e.g., its likelihood of failure). Current emphasis is appropriately on high-hazard dams, but there can be a wide disparity in the consequences of failures of these structures. Other consequences of dam failure, such as economic and environmental losses, are qualitatively evaluated and defined in equally broad terms. The hazard classification process does not include an assessment of the sociological or other effects on a community, nor does it consider the broader local and regional effects (economic and other) of the loss of a critical infrastructure (power, water supply, flood protection). Hazard classification is assigned primarily by state or federal regulatory agencies. The Federal Emergency Management Agency guidance states that classifications \"should be based on the worst-case, probable scenario of failure or mis-operation of the dam, i.e., the assigned classification should be based on failure consequences that will result in the assignment of the highest hazard potential classification of all probable failure and mis-operation scenarios\" .

1. Currently, levees in the United States have not been catalogued, nor is there a uniform method
for assessing them. Why might this be?
Solution
Levees and floodwalls, hereafter referred to as levees, have been part of flood management in the
United States since the late 1700s because they are relatively easy to build and a reasonable
infrastructure investment. A levee is a “man-made structure, usually an earthen embankment,
designed and constructed in accordance with sound engineering practices to contain, control, or
divert the flow of water so as to provide protection from temporary flooding.
A levee system is a “flood protection system which consists of a levee, or levees, and
associated structures, such as closure and drainage devices, which are constructed and operated
in accordance with sound engineering practices.― Under NFIP regulations, homes and
commercial buildings located in the SFHA within a participating community may be exempted
from the MPR and land-use regulations when located behind a levee system that has been
recognized by FEMA as providing protection against the one percent annual chance flood.
The National Inventory of Dams (NID) hazard classification system is broad, qualitative, and
based on the potential threat to life and property in the event of dam failure. A dam is given a
"high" hazard rating if its failure can result in fatalities, whether the dam is small or large and
has the potential for a single or thousands of fatalities. The rating is also regardless of its
condition (e.g., its likelihood of failure). Current emphasis is appropriately on high-hazard dams,
but there can be a wide disparity in the consequences of failures of these structures. Other
consequences of dam failure, such as economic and environmental losses, are qualitatively
evaluated and defined in equally broad terms. The hazard classification process does not include
an assessment of the sociological or other effects on a community, nor does it consider the
broader local and regional effects (economic and other) of the loss of a critical infrastructure
(power, water supply, flood protection). Hazard classification is assigned primarily by state or
federal regulatory agencies. The Federal Emergency Management Agency guidance states that
classifications "should be based on the worst-case, probable scenario of failure or mis-operation
of the dam, i.e., the assigned classification should be based on failure consequences that will
result in the assignment of the highest hazard potential classification of all probable failure and
mis-operation scenarios"