FLOOD06680

• County: Statewide
• Basin: Statewide
• Title: Flood Damage in the United States, 1926-2000
• Date: 6/1/2000
• Prepared By: NOAA
• Floodplain - Doc Type: Flood Documentation Report

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Post-flood reports prepared by district offices of the U.S, Army Corps of Engineers
(USACE) often provide fairly detailed damage estimates that are more complete than NWS
estimates because they are compiled rnany months after the flood event. The Tennessee Valley
Authority (TV A) publishes post-flood reports, similar to US ACE reports, for areas of the
southeastern U,S, under its jurisdiction, Post-flood reports from USGS, NOAA, and the U.S.
Weather Bureau usually focus on hydrological and meteorological conditions preceding and
during the flood event, with only brief mention of damage, If damage estimates are provided,
often they are obtained from the NWS or the USACE.

FEMA has appointed special task forces to study particular major floods and recommend
mitigation measures (for example, Interagency Hazard Mitigation Teams for each state affected
by the 1993 Midwest flood), Their reports often contain damage estimates,

National Water Summary 1988-1989: Hydrologic Events and Floods and Droughts
(USGS 1991) provides historical flood information for all fifty states through 1989, In
particular, floods that are considered major historical events for each state are listed, including
some damage estimates for individual floods,

State Reports
State government agencies occasionally publish post-flood reports after particular flood
events, To obtain additional, perhaps unpublished, information, we wrote to emergency
management agencies in each state, asking them to provide information about historical flood
damage, Five states were able to provide long,term historical summaries of their damaging
floods, and these proved invaluable for analyzing the accuracy of the NWS estimates (see
Section 5), Other states sent shorter-term information which provided useful examples,

Unpublished NWS Damage Information
The NWS-IDC staff provided copies of their state and national flood damage data sets,
These data sets included unpublished estimates for 1976-1982; however, the state and national
estimates were found to be incompatible, as described in Section 3, Staff members also gave us
access to the historical archives at their office in Silver Spring, MD. Two sets of files proved
helpful in understanding how damage estimates were compiled in the past, and were used to
supplement estimates for 1976-1982,

Monthly files for 1971-1995 contain the original flood reports from field offices allover
the D,S" in no particular order. (These were discontinued when electronic submission of reports
began in 1996,) The reports often contain descriptions of damage, but only occasionally provide
damage estimates, They do not provide a basis for computing total damage by state or river
basin.

Yearly files contain notes made by the people who compiled damage estimates, as well as
news clippings and agency communications during the year, These are extremely helpful in
developing estimates for 1976-1979, as they contain preliminary annual damage estimates with
notes on when and where major floods occurred.

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