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<br />coast state has a hurricane preparedness plan completed or undenvay. Nlany
<br />localities also have emergency management plans, but relatively few have
<br />detailed plans specifically for floods, and even fewer have plans for mitigation
<br />after a flood. This is probably due to lack of expertise and funding to develop
<br />such plans, the hope that the flood problems will be taken care of through
<br />some structural measures, and the expectation of receiving federal disaster
<br />assistance when the flood does occur.
<br />
<br />Flood Forecasting, Warning, and Emergency Plans
<br />
<br />\-\farning systems and accompanying emergency response have long
<br />been recognized as effective \vays to save lives and reduce flood damages in
<br />both riverine and coastal floodprone areas. The joint hurricane evacuation
<br />study is a good example of this. As the cost of the required equipment con-
<br />tinues to decrease, more and more state and local governments are funding
<br />the development of flood warning systems and emergency plans.
<br />The National \-"'eather Service conducts research, provides specific
<br />flood forecast and warning services to over 3,100 communities, and works
<br />with many of the 900 communities that have local warning systems. The
<br />Corps, the Tennessee Valley Authority, and the Bureau of Reclamation collect
<br />hydrometeorological data and prepare operational forecasts, often in coopera-
<br />tion with the National ''''eather Service, for their flood control structures. The
<br />U.S. Geological Survey collects streamflow and other data that can be used
<br />for flood forecasting.
<br />About half of the states are involved in flood warning, including coop-
<br />eration in IFLOWS (the Integrated Flood Observing and \-\tarning System)
<br />in Appalachia and installation of automated data collection equipment. Some
<br />large urban communities have included forecasting and preparedness planning
<br />in their operations for years, participated in regional warning systems, or have
<br />developed their own systems.
<br />University and private research has contributed substantially to the
<br />knowledge about and design of warning systems, disaster response, and sys-
<br />tem effectiveness. The private sector is vital to the design, installation, opera-
<br />tion, maintenance, and modification of local flood warning systems. In many
<br />instances, industries have cooperated in the installation and operation of flood
<br />warning systems and reduced their own flood losses.
<br />
<br />Floodproofing and Elevation
<br />
<br />Floodproofing is the use of permanent, contingent, or emergency tech-
<br />niques to either prevent flood waters from entering buildings or to minimize
<br />the damages from water that does get in. Some of the techniques involve
<br />using water-tight seals, closures or barriers; using water-resistant materials;
<br />and temporarily relocating the contents of a building. Elevating a structure
<br />means raising it on fill, piers, or pilings so that it is above expected flood
<br />levels. I\.fost new floodplain structures are now designed to incorporate flood.
<br />proofing and/or elevation, primarily because it is required by the regulations
<br />of all National Flood Insurance Program communities. There are millions
<br />of existing flood prone homes to which flood proofing could be applied retro-
<br />actively ("retrofitted"), but this technique is not yet routinely used. One
<br />obstacle has been that flood insurance rates stay the same when a residence
<br />is retrofitted; the new Community Rating System of the National Flood
<br />Insurance Program should help remove that disincentive.
<br />Floodproofing is probably the tool most widely used by the private sector
<br />with only limited government assistance. Many of the early flood proofing tech-
<br />niques were developed by architects, engineers, and building contractors as
<br />they worked with individual property O\vners, especially on small commercial
<br />buildings and industrial facilities. The American Institute of Architects, the
<br />National Association of Homebuilders, university researchers, and private engi-
<br />neering firms have conducted considerable research on and developed techni-
<br />cal information about floodproofing. The private sector is also the source of
<br />many flood proofing products, such as vinyl sheathing, devices to prevent sewer
<br />backflow, substitutes for sand bags, equipment for filling sand bags, and flood
<br />shields to temporarily seal windows, doors, and other openings.
<br />
<br />LYCOMING COUNTY'S EARLY
<br />WARNING SYSTEM
<br />
<br />
<br />l~ycoming County. Pen'flS)'lvania, lies almost entire!;'
<br />within the drainage area of the Hist Braru:h f?f the
<br />Susquehanna River and conlf1i'flS close to 2,200 mws
<br />of streams. .-Host f?f the counry's people live 011 or
<br />near the river. ,ifter major flooding from Hurriranes
<br />Agnes in 1972 and Eloise in 1975, a self-help ear!;'
<br />warning s)'Stem was developed It)ith an initinl
<br />investment if $500. lVith the help of the National
<br />J-'J..eather Service, forecasting procedureJ were estab-
<br />lished jar each walfrshed within the county, and the
<br />s)'Stem was put into operation. within three month
<br />Over 100 volunteer observers were recruited and
<br />trained to obstTve and 17Wnitor stream gages and
<br />mala reports to a stream coordinator. The coordiTUl-
<br />tor assembles the dam for a watershed and conveys it
<br />to a system coordi1U1tor. With tlu help qf expert per-
<br />sonnel, the dam is waluated and a determination of
<br />expeckd flooding and appropriak response is made.
<br />
<br />Over the unt 10 )Jears imprm_'emmts t-O the spum
<br />hau. been mo.de. w assure adequate backup for data
<br />lransmission, the county proVIded National Oceanic
<br />and Atmospherit' Administration weather radios to
<br />the volunteer observers, and Nl"VS distributed base
<br />slnlion radios to thf stream coordirw.tors. In midi-
<br />lion, a spkm of 10 automated rain gages and 4
<br />automaud stream alarm devices was insto.lled to
<br />supplernent the mnnua/ dnto. collection.
<br />
<br />Examples of Retrofitting
<br />
<br />~~.
<br />, ,
<br />,
<br />
<br />Rclocation:Movingabuildingt<>highground,
<br />above flood 1e"c1s.
<br />
<br />(~
<br />1,-:/
<br />
<br />Elevalion:Raisingabuildingsotbatflood..atcrs
<br />will go undcril.
<br />
<br />c.
<br />.,J
<br />
<br />Floodwalh: Building a wall ofconcrelc orcanh
<br />10 kec:p flood watcrs from reaching a building
<br />
<br />=*'
<br />
<br />Dry Floodpmofing: Making building walls
<br />walcrtighl ilnd scaling openings 10 flood watcrs
<br />cannOlcnlcr.
<br />
<br />.'/-""..
<br />~
<br />
<br />Wet Floodproofing: A1tcring a build inK 10
<br />minimize d:am:agc whcn flood walers Cllter.
<br />
<br />Suum: Fwodpr(JOj &trojitling: Homt/J1Jft/lT Sdj-PrfJi<<llw &haWJr,
<br />Shirley Bradway Laska, 1991
<br />
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