Well tracers are now available for installation in existing wells, not only in the initial completion. The tool has functionality to detect which part of the wellbore that produces water, without any logging necessary. The tool can be installed retrofit anywhere in the reservoir section, inside in the liner or screen. There are two available versions, the “RIT Zone Selective” is designed to detect if water is produced from the adjacent perforations at the installation depth, and the “RIT Upstream” which is designed to detect all upstream water production. Read more.