Effects Of Flood Plain Encroachments On Peak Flow

Author : L. A. Traille
Publisher :
ISBN 13 :
Total Pages : 157 pages
Book Rating : 4.:/5 (959 download)

DOWNLOAD NOW!

Download or read book Flow Modifications by Storage Loss Through Flood Plain Encroachment written by L. A. Traille and published by . This book was released on 1982 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: When highways and other developments encroach on natural stream valleys, they act to obstruct the flow and consequently modify natural flooding characteristics. The impact of a particular channel or flood plain encroachment on flooding is governed by the degree it alters natural valley properties, as well as orientation or alignment with respect to flow. Most encroachments can be classified as either lateral or transverse to the flow, although an embankment aligned with an acute skew angle could be considered both lateral and transverse. Alteration of the natural floodway through the loss of overbank storage and the resulting constriction of the flow will ultimately result in increased flood stages and peak discharges, as well as scouring of the main channel bed. Assessing impacts on flow of a design alternative is important in preliminary design stages. At present this can only be achieved through the use of complex models requiring considerable data collection and preparation. To avoid such lengthy procedures, there is urgent need for simpler techniques that would use minimum amounts of input data without seriously sacrificing accuracy. The objective of NCHRP Project 15-7 is to develop simple short-cut procedures for assessing changes in water surface profiles, peak discharges, and scour. As they are intended for use in preliminary estimates, the results of this study in no way substitute for the detailed procedures required in final design studies. These procedures emphasize predicting changes rather than developing absolute values.