Completion technologies and programs have had significant improvements throughout the last two decades. But water-production problems associated with channeling, cross flow, and coning still prevail in many areas. In addition to undesirable effects of the water on the surface and subsurface equipment, the cost of handling the water in producing wells can seriously reduce the profitability of the well. Diagnosing the causes of water-control problems has long been a major hurdle to operational economics.
In the past two decades, water-control technologies have also evolved and developed significantly. This paper is a review of those technologies. It covers the gamut of water-control-related problems that can arise during the life of a well. A decision-matrix chart depicting types of water-control problems with the appropriate water-control technology is given. Case-history references for each solution category are also presented. The paper classifies different types of water-production problems keyed by their onset mechanisms. It also presents a review of the methods and limitations of the current water-control processes. A special emphasis is placed on the description of solutions to the water-control problems that are linked to hydraulic-fracture stimulation of reservoirs. The paper discusses the water-control management issues in the following categories: (1) prediagnostic evaluation, (2) problem identification, (3) diagnostic evaluation, (4) treatment-design considerations, (5) chemical water-control technologies, and (6) case-history references for each problem-solution category.
Information presented in this paper will provide a completion engineer a good understanding of the range of water-control issues and give a methodical approach to selecting appropriate and optimum solutions that have evolved in the last two decades.