Evaluating temporal changes in hydraulic conductivities near karst-terrain dams: Dokan Dam (Kurdistan-Iraq)

Dafny, Elad and Tawfeeq, Kochar Jamal and Ghabraie, Kazem (2015) Evaluating temporal changes in hydraulic conductivities near karst-terrain dams: Dokan Dam (Kurdistan-Iraq). Journal of Hydrology, 529 (Part 1). pp. 265-275. ISSN 0022-1694

Abstract

Dam sites provide an outstanding opportunity to explore dynamic changes in the groundwater flow regime because of the high hydraulic gradient rapidly induced in their surroundings. This paper investigates the temporal changes of the hydraulic conductivities of the rocks and engineered structures via a thorough analysis of hydrological data collected at the Dokam Dam, Iraq, and a numerical model that simulates the Darcian component of the seepage. Analysis of the data indicates increased seepage with time and suggests that the hydraulic conductivity of the rocks increased as the conductivity of the grout curtain decreased. Conductivity changes on the order of 10-8 m/s, in a 20-yr period were quantified using the numerical analysis. It is postulated that the changes in hydraulic properties in the vicinity of Dokan Dam are due to suspension of fine materials, interbedded in small fissures in the rocks, and re-settlement of these materials along the curtain. Consequently, the importance of the grout curtain to minimize the downstream seepage, not only as a result of the conductivity contrast with the rocks, but also as a barrier to suspended clay sediments, is demonstrated. The numerical analysis also helped us to estimate the proportion
of the disconnected karstic conduit flow to the overall flow.


Statistics for USQ ePrint 27685
Statistics for this ePrint Item
Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Additional Information: Files associated with this item cannot be displayed due to copyright restrictions.
Faculty / Department / School: Current - Faculty of Health, Engineering and Sciences - School of Civil Engineering and Surveying
Date Deposited: 14 Jun 2016 02:48
Last Modified: 04 Apr 2017 23:23
Uncontrolled Keywords: hydraulic conductivity; dam; karst; temporal changes; seepage modeling
Fields of Research : 01 Mathematical Sciences > 0103 Numerical and Computational Mathematics > 010301 Numerical Analysis
04 Earth Sciences > 0406 Physical Geography and Environmental Geoscience > 040603 Hydrogeology
09 Engineering > 0905 Civil Engineering > 090509 Water Resources Engineering
Socio-Economic Objective: D Environment > 96 Environment > 9610 Natural Hazards > 961008 Natural Hazards in Mountain and High Country Environments
Identification Number or DOI: 10.1016/j.jhydrol.2015.07.048
URI: http://eprints.usq.edu.au/id/eprint/27685

Actions (login required)

View Item Archive Repository Staff Only