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Irrigation and Drainage Systems

, Volume 11, Issue 2, pp 171–184 | Cite as

Flow resistance and hydraulic capacity of water courses with aquatic weed growth. Part 2

  • E.P. Querner
Article

Abstract

The flow resistance is generally derived from fieldmeasurements, using the total wetted area of the cross-section.Less attention has been paid to the aquatic weed growth stageand often different resistance have been derived. In this paperthe flow resistance required in the Manning formula wascalculated from laboratory experiments and field data. A goodsolution appeared to be using the unobstructed part of the cross-section only and excluding the part covered by weeds. Apractical solution was found using the relative weed obstructionin the water courses to represent the weed growth. Weedobstruction was measured throughout the growing season. Thedata were obtained from water courses without any weedcontrol and also in sections where weeds were cleared twiceduring the growing season.

flow resistance laboratory experiments unobstructed part weed growth hydraulic radius drainage canal 

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References

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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • E.P. Querner
    • 1
  1. 1.Soil and Water Research (SC-DLO)DLO Winand Staring Centre for Integrated LandWageningenThe Netherlands

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