Rosemary Lemonade

From the Cafe Flora Cookbook by Catherine Geier and Carol Brown.
Ingredients:
1 bunch rosemary (8 sprigs)
4 cups water, plus more as needed
1 cup sugar
1 cup freshly squeezed lemon juice (about 6 lemons)

In a saucepan, cover the rosemary with the 4 cups water. Bring to a boil and simmer for 20 minutes. Strain the rosemary water into a 2 quart pitcher and dissolve the sugar in the hot rosemary water. Set aside to cool.
When the rosemary tea is cool, add the lemon juice and enough water to make 2 quarts. Serve chilled.