THE DRAWDOWN NEAR AN ABSTRACTION WELL OF LARGE DIAMETER UNDER NON-STEADY CONDITIONS IN AN UNCONFINED AQUIFER

A new equation is derived for the drawdown in a uniform anisotropic aquifer under water-table conditions. The abstraction well, which is pumped at a constant rate, may be of any finite diameter and well storage is taken into account. The mathematical solution also allows for the following factors. The compressibility of the aquifer, the depth at which the drawdown in an observation well is measured and the partial penetration of the abstraction well. Tables of computed values of the drawdown equation are given. Using these and other published tables, a procedure is outlined for finding the coefficients of permeability and storage from pumping-test data. Curves plotted from the computed values show clearly the effect of the finite size of the abstraction well on the drawdown and, also, the effect of water table as compared with confined conditions. /Author/

• Corporate Authors:

  Elsevier

  Radarweg 29
  Amsterdam,   Netherlands  1043 NX
• Authors:
  • Boulton, N S
  • Streltsova, T D
• Publication Date: 1976-5

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 29-46
• Serial:
  • Journal of Hydrology
  • Volume: 30
  • Issue Number: 1/2

Subject/Index Terms

• TRT Terms: Anisotropy (Physics); Aquifers; Drawdown (Hydraulics); Equations; Flow; Mathematical analysis; Observation wells; Permeability coefficient; Pumping tests; Soil mechanics; Water storage; Water table; Wells
• Old TRIS Terms: Anisotropic flow; Drawdown
• Subject Areas: Bridges and other structures; Geotechnology; Highways; Hydraulics and Hydrology;

Filing Info

• Accession Number: 00158176
• Record Type: Publication
• Files: TRIS
• Created Date: Sep 28 1977 12:00AM