In a saucepan, bring peaches, sugar, and 2 cups of the water to a boil. Simmer for 10 minutes.

Blend the mixture until smooth using an immersion or regular blender.

Strain the puree through a fine mesh strainer, pressing to extract juice. Discard solids.

Cool the mixture completely.

In a pitcher, mix the cooled peach base with lemon juice and remaining 3 cups of water.

Stir well. Serve chilled over ice with garnish if desired.