Here's your answer -
"The amount of alcohol in the blood is called blood alcohol content or blood alcohol concentration
(BAC). Alcohol is metabolized at the rate of .015 of (BAC) every hour.
For instance, a person with a BAC of .15 (this BAC is almost twice the legal amount when driving) will have no measurable alcohol in the bloodstream ten hours after the last drink (.15 divided by .015 = 10).
With some urine alcohol tests, alcohol can be detected up to around 48 hours after a person has ingested alcohol. With the EtG Urine Alcohol Test, however the presence of EtG in the urine demonstrates that ethanol alcohol was ingested within the past 3 or 4 days, or roughly 80 hours after the ethanol alcohol has been metabolized by the body.
As a result, it can be determined that a urine alcohol test employing EtG is a more accurate indicator of the recent consumption of alcohol as opposed to simply measuring for the existence of ethanol alcohol (as is done many other urine alcohol tests).
With the EtG Urine Alcohol Test, however, the presence of EtG in the urine reveals that ethanol alcohol was consumed within the past 80 hours or so which could mean many hours after the ethanol alcohol has been metabolized by the body."
Drinking as much water as you possibly can in order to water down your urine shows up on an EtG test as just that - an attempt to water down your urine.
How Long Will Alcohol Stay In the System For Urine Tests