FLOOD07354 - Laserfiche WebLink

Home Browse Search

Elevatin~ Structures on Piles or Columns. This method is frequently used where the dynamic forces of wave action or the velocity of flood"ater is severe, where the "ater surface can vary considerably, or where it is desired that floodwater pass beneath the structure so that flood plain obstruction does not occur. Structures built on piles are often found in coastal areas, along lake shores , or in designated floodways in riverine areas if allowed by State statute, One advantage to this method is t~at floodwater impediment and impacts on flood storage capacity are minimized, Also, open areas under the structure can be used for parking or storing materials that can easily be moved. Even though the best time to flood proof is obviously during initial construction. this method is ofcen the most practical for flood proofing existing structures on conventiQbal foundations. E1evatinE Structures on Fill. This method is a fairly common activity in subdivision development and in siting individual houses. This is often relatively easy ~o accomplish in new development. Many times site grading for drainage in combination with the use of a conventional foundation will raise the first-floor level above the design flood level. Significant amounts of material hauled into a flood plain for this purpose may obstruct the natural flow of water or resul~ in a loss of floodwater scorage capacity. Either condition can , . cause'higher and more frequent flooding, B<<fore a structure is: placed on fill, State and local land use regulations should be checked to determine if such accion is allowed. The materials used for fill vary widely from one region to the nexc, but generally the material must be grassed or otherwise protected against erosion. Constructin~ Local Levees and Floodwa1ls~ ... . The levees considered as nonstructural measures are around single homes, small subdivisions, or indiVidual , those built industrial 29