Straight-Line Method Generalization for Aquifer Parameter Estimations

Sen Z.

JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING, vol.138, no.12, pp.1082-1087, 2012 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 138 Issue: 12
  • Publication Date: 2012
  • Doi Number: 10.1061/(asce)ir.1943-4774.0000521
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.1082-1087


Aquifer parameter determination in practical hydrogeological studies exposes one of the most significant steps in groundwater resources assessment and management. Successful parameter estimation necessitates both a reliable methodology and field data. Different analytical solutions in the forms of type curves depend on well and aquifer configuration such as porous or fractured media; confined, unconfined, and leaky conditions; and small-and large-diameter wells. Most often Cooper-Jacob (CJ) straight line is used for aquifer parameter estimations from late time-drawdown data in cases of confined and unconfined aquifers. This straight-line method is attractive because of its simplicity and straightforward calculations without tedious and dubious type-curve matching procedure. The warranty of the CJ method application depends on the fact that the late time-drawdown measurements fall along the final portion of the Theis type curve. The main purpose of this paper is to present a general type straight-line model to determine aquifer properties of a confined leaky (semiconfined) aquifer by using the pumping test results. The CJ method is applicable in cases in which the straight-line slope on dimensionless semilogarithmic paper is equal to 2.3 only. DOI: 10.1061/(ASCE)IR.1943-4774.0000521. (C) 2012 American Society of Civil Engineers.