Detection of Buried Utilities Using Electrical Resistivity Imaging (ERI) Technique

Abstract

The main objective ofthis paper is to show the ability of resistivity technique for investigating the buried utilities (their location and depth) for characterizing the surrounding subsurfacesoils. This study deals with implementation of 2-D electrical resistivity imaging (ERI) to detect the location of buried utilities existing in the Al-Dhubat Interchange in Kut city, Wassit Governorate south of Baghdad. Interpretation results of the subsurface investigation of this site have been compared with those obtained from conventional methods.Generally, the site is characterized by its gradual decreases in resistivity with depth with range of resistivity values (<1-140 ohm.m) which is mostly consisting of silty clay to clayey silt with lenses or pockets of medium, stiff and very stiff silty clay with sand or gravel. Several utility pipes with different diameters of φ1200, φ1100, φ600 and φ 400 mm with low resistivity values (<1 ohm.m) have been identified in the 2-D resistivity sections.The results of 1-D VES agree with that of 2-D ERI as their resistivity values decrease with depth. Besides, IP values for this site agree with the resistivity data as it is an indicator of clay content and their uniform sections reflecting the high moisture content and the effect of salts in the subsurface soil and water.

Keywords

• delectrical resistivity imaging
• dves
• induced polarization
• buried utilities