Yes, you can safely drink the tap water at Mandalay Bay and throughout the Las Vegas Strip. The water is provided by the Southern Nevada Water Authority and meets or exceeds all federal Safe Drinking Water Act standards. However, many guests find the taste unappealing because the water is "hard," meaning it has a high mineral content (calcium and magnesium) and is heavily treated with chlorine. This can give it a slight chemical or "metallic" aftertaste. While it is perfectly safe for brushing your teeth or drinking in a pinch, most travelers prefer the taste of filtered or bottled water. If you want to avoid the high cost of hotel mini-bar water, you can bring a reusable bottle with a built-in filter, which will remove the chlorine taste while keeping you hydrated in the dry Nevada desert heat. The hotel also provides ice machines on every floor, which utilize the same municipal water but are often filtered at the machine level.