Roughness Values for Overland Flow in Subcatchments

Liong, Shie‐Yui; Selvalingam, S.; Brady, D.K.

doi:10.1061/(asce)0733-9437(1989)115:2(203)

Cited by 13 publications

(4 citation statements)

References 5 publications

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“…As noted by several authors (Prosser and Slade, 1994;Prosser and Abernethy, 1996), the determination of erosion thresholds shows low sensitivity to the value of the flow resistance, n and differences of more than one order of magnitude are necessary to produce significant changes. Several studies have proposed values of n between 0.05 and 0.20 s m − 1/3 , depending on the type of vegetation or land use (Engman, 1986;United States Department of Agriculture, 1986;Liong et al, 1989;Jain and Singh, 2005). Based on existing information on vegetation cover and land use (Consejería de Medio Ambiente, 2007), distributed values of between 0.05 and 0.1 s m − 1/3 with an average of n = 0.07 s m − 1/3 were used in this work.…”

Section: Channel-head Location Modelmentioning

confidence: 99%

Scale effects on the estimation of erosion thresholds through a distributed and physically-based hydrological model

2012

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Section: Channel-head Location Modelmentioning

confidence: 99%

Scale effects on the estimation of erosion thresholds through a distributed and physically-based hydrological model

2012

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“…The three maps (two if vegetation is taken from the land use) are used to develop a combined land use/soil type/vegetation map, each combination having a unique set of parameters. Applicable literature values from a variety of sources (Rawls et al 1982(Rawls et al , 1983Pielke, 1984;Liong et al, 1989;Bras 1990) are then used to assign initial values of saturated hydraulic conductivity, capillary head, porosity, retention depth, overland flow roughness coefficient. If long-term simulations are being conducted then wilting point is assigned for the Deadroff method, and shortwave radiation albedo, vegetative resistance height, canopy-average stomatal resistance and canopy shortwave radiation transmission are assigned for the Penmann-Monteith method.…”

Section: Senerathmentioning

confidence: 99%

“…Literature values for a single parameter, from a single reference, for a single land use may have a range of values of overland Manning roughness coefficient of greater than (C/ ) 100% (Liong et al, 1989). Even larger ranges can be found for soil hydraulic properties estimated from crude soil textural classification (Rawls et al, 1982(Rawls et al, , 1983.…”

Section: Senerathmentioning

confidence: 99%

Theory, development, and applicability of the surface water hydrologic model CASC2D

Downer

Ogden

Martin

et al. 2002

Hydrological Processes

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Abstract:Numerical tests indicate that Hortonian runoff mechanisms benefit from scaling effects that non-Hortonian runoff mechanisms do not share. This potentially makes Hortonian watersheds more amenable to physically based modelling provided that the physically based model employed properly accounts for rainfall distribution and initial soil moisture conditions, to which these types of model are highly sensitive. The distributed Hortonian runoff model CASC2D has been developed and tested for the US Army over the past decade. The purpose of the model is to provide the Army with superior predictions of runoff and stream-flow compared with the standard lumped parameter model HEC-1. The model is also to be used to help minimize negative effects on the landscape caused by US armed forces training activities. Development of the CASC2D model is complete and the model has been tested and applied at several locations. These applications indicate that the model can realistically reproduce hydrographs when properly applied. These applications also indicate that there may be many situations where the model is inadequate. Because of this, the Army is pursuing development of a new model, GSSHA, that will provide improved numerical stability and incorporate additional stream-flow-producing mechanisms and improved hydraulics.

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“…117, No. 4, July/August, 1991 Liong et al (1989) developed a simple method for assigning Manning roughness coefficients to overland flow segments in kinematic wave models. The proposed method was found to work well on a gaged basin.…”

Section: Introductionmentioning

confidence: 99%

Roughness Coefficients for Selected Residue Materials

Gilley

Kottwitz

Wieman

1991

J. Irrig. Drain Eng.

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Analysis of surface runoff on upland areas requires identification of roughness coefficients. A laboratory study is conducted to measure Darcy-Weisbach and Manning roughness coefficients for corn, cotton, peanut, pine needles, sorghum, soybeans, sunflower, and wheat residue. Varying rates of flow are introduced into a flume in which selected amounts of residue are securely attached. Roughness coefficients are calculated from measurements of discharge rate and flow velocity. The laboratory data are used to derive regression equations for relating roughness coefficients to Reynolds number and either percent residue cover or residue rate. Separate equations are developed for Reynolds number values from 500 to 20,000, and from 20,000 to 110,000. Generalized equations are presented for estimating roughness coefficients for other residue materials not used in this investigation. Accurate prediction of roughness coefficients for residue materials will improve our ability to understand and properly model upland flow hydraulics.

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Roughness Values for Overland Flow in Subcatchments

Cited by 13 publications

References 5 publications

Scale effects on the estimation of erosion thresholds through a distributed and physically-based hydrological model

Scale effects on the estimation of erosion thresholds through a distributed and physically-based hydrological model

Theory, development, and applicability of the surface water hydrologic model CASC2D

Roughness Coefficients for Selected Residue Materials

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