Too much of anything is bad. This principle applies even when it comes to drinking water.
Undoubtedly drinking water helps the kidneys function properly, prevent the body from getting dehydrated and helps clear skin. However, drinking excess of water can be harmful. Two deaths were reported of high school students from U.S. Both were foot ball players and they died of exercise-associated hyponatremia (low sodium levels in blood). Hyponatremia may occur when you take in more fluids than the body requires. Having too many fluids causes the cells to swell. This leads to muscle cramps, nausea and vomiting. The shocking news is that hyponatremia has been the cause of death in more than a dozen runners in the recent years.
To know more on why too much water is bad read health24.