flood routing - dr. iwan krida

FLOOD

ROUTINGIwan Kridasantausa

Flow Routing

Procedure to determine the flow hydrograph at a point on a watershed from a known hydrograph upstream

As the hydrograph travels, it attenuates gets delayed

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Why route flows?

Account for changes in flow hydrograph as a flood wave passes downstream

This helps in Accounting for storages Studying the attenuation of flood peaks

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EXAMPLE 1

Storage Computations

SOLUTION…

(a)

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EXAMPLE 2

River and Reservoir Routing Concepts

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HYDROLOGIC RIVER ROUTING

FIGURE 4.2 STORAGE IN A RIVER REACH

FIGURE 4.3 PRISM AND WEDGE STORAGE CONCEPT

(4.2)

MUSKINGUM METHOD

Where

(4.3)

(4.4)

(4.5)

(4.6)

(4.7)

(4.8)

(4.9)

(4.10)

EXAMPLE 3Muskingum Routing

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DETERMINATION OF STORAGE CONSTANT

Figure 4.4 Selection of Muskingum Coefficients

EXAMPLE 4

Determination of The Muskingum Routing Coefficients

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HYDROLOGIC RESERVOIR ROUTING

Storage Indication Method

(4.13)

EXAMPLE 5

Storage Indication Rounting