Considerations for measuring pressure head and water content in inclined boreholes

A. C. Hinnell, Paul A Ferre

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Angled boreholes have been proposed to improve water content and pressure head monitoring in deep vadose zones by reducing the impact of the borehole on measurements by placing sensors below undisturbed soil. However, the borehole casing distorts the flow field, which may impact measurements made with sensors placed on or in the boreholes. We examined a wide range of soil types, background fluxes, and casing radii and angles of inclination to predict the error in water content and pressure head measurements that arise due to this flow disruption under unit gradient flow. We found that placing pressure head and water content sensors 110° and 120° from the top of the borehole, respectively, minimizes the effects of flow perturbation. Under some conditions, it may be possible to use the perturbation of the flow field caused by the casing to estimate hydraulic parameter values.

Original languageEnglish (US)
Article numberW12444
JournalWater Resources Research
Volume44
Issue number12
DOIs
StatePublished - Dec 2008

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borehole
water content
sensor
flow field
perturbation
vadose zone
soil type
measuring
hydraulics
monitoring
soil

ASJC Scopus subject areas

  • Water Science and Technology

Cite this

Considerations for measuring pressure head and water content in inclined boreholes. / Hinnell, A. C.; Ferre, Paul A.

In: Water Resources Research, Vol. 44, No. 12, W12444, 12.2008.

Research output: Contribution to journalArticle

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