Usually, alcohol would stay within your system for around 24 hours after you have had a few drinks and this would be the time period during which it would be detectable in your urine. However, there are a few special tests which can detect its presence in urine for up to 48 hours.o, the question of how long alcohol is detectable in urine or how long does alcohol stay in your system depends on the rate at which your body would break it down. Usually, normal human beings metabolize wine at about the same rate which is around 0.015 BAC per 60 minutes.