Add the cucumber slices and 8 cups of cold water to a large pitcher.
Refrigerate for at least 1 hour to allow the cucumber flavor to infuse the water.
Before serving, gently press the cucumber slices with a wooden spoon to release additional flavor.
Serve chilled.
Notes
Cucumber water is best served the same day but can be stored covered in the refrigerator for up to 3 days.For additional flavor, add fresh lemon slices or mint. Sparkling water can also be used in place of some or all of the still water.