In large heatproof measure or bowl, steep tea in 8 cups boiling water for 5 minutes. Discard bags.
Meanwhile, in large saucepan, bring blueberries and 1 cup water to boil. Reduce heat and simmer, stirring often, until blueberries break down, about 5 minutes. Add to tea.
Add brown sugar and let cool to room temperature, about 30 minutes. Refrigerate for at least 2 hours.
Strain through cheesecloth-lined sieve into pitcher, pressing solids gently so beverage stays clear. Stir in lemon juice. Serve over ice cubes. Garnish with lemon wedges.