Will drinking large amount of water pass drug test?

Sometimes. This is known as purging; the principle is this: your body produces urine so fast that nothing is passed through the urine in detectable amounts. This is pretty risky, and really shouldn't be relied upon. A better strategy is to simply not do drugs.

Many swear by this strategy, and it seems to work fairly well. But in many cases, purging produces urine that is so dilute that validity tests can't even identify it as urine. That can be a tipoff to the tester that the testee has been purging. Often, when a test is inconclusive, an employer will ask for a repeat test, and won't hire someone with repeated inconclusive tests.