Yes it is, I tried it and I didn't die! *crickets* Neither did my stomach churn. But seriously, after I tried I read that it is really safe to drink water from the faucet here. Just avoid the hot water because it contains high levels of copper.
I did buy bottled water, but I want tap water for my coffee because coffee tastes better with it! I also want to be sulit (cost-effective, frugal, economical) at the same time, haha! Fine, kuripot na ko!
Maybe next time it is better to read first before trying it out for myself. Just a thought :)