a. The streamflow from a 500-hectare catchment due to a storm of constant intensity of 27mm/h for four hours can be represented by a triangle in which the peak flow was 25 m3/s. The flow lasted six (6) hours and peaked at two (2) hours. The soil texture is uniform throughout the catchment and when the surface is ponded, its infiltration rate varies according to the Horton equation, with a decay constant, k, of 0.5 h1 and a maximum infiltration rate, fo, of 24 mm/h. Use the information to determine; i. the volume of infiltration (mm); ii. the infiltration rate at soil saturation (mm/h); and ii. the runoff coefficient of the catchment. iv. State your assumptions.

a. The streamflow from a 500-hectare catchment due to a storm of constant intensity of 27mm/h for four hours can be represented by a triangle in which the peak flow was 25 m3/s. The flow lasted six (6) hours and peaked at two (2) hours. The soil texture is uniform throughout the catchment and when the surface is ponded, its infiltration rate varies according to the Horton equation, with a decay constant, k, of 0.5 h1 and a maximum infiltration rate, fo, of 24 mm/h. Use the information to determine; i. the volume of infiltration (mm); ii. the infiltration rate at soil saturation (mm/h); and ii. the runoff coefficient of the catchment. iv. State your assumptions.

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter7: Permeability

Section: Chapter Questions

Problem 7.4P

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