Box turtles are not aquatic, but they do require access to water to stay hydrated. A small bowl of water in their pen, tank, or enclosure will be sufficient, but the water should always be kept clean and fresh. Generally, their water dishes should be cleaned daily to avoid biofilm from forming and to maintain freshness, but they may require additional cleaning if soiled throughout the day.
Water dishes should remain low enough so the turtle has the ability to crawl in and out. The water level should also be kept low enough to avoid the threat of drowning.
Fast Fact
Box turtles enjoy a soak now and then. Consider adding a larger pool of water to their enclosures that they can climb into. Don't be surprised if your turtle decides to poop there.