In a medium saucepan set over medium high heat, combine the blueberries, sugar and 1 cup water. Stir until the sugar dissolves. Continue cooking until the mixture turns purple and blueberries are soft, about 10 minutes. Allow to cool to room temperature.
In a pitcher, combine together the blueberries/sugar mixture, lemon juice and remaining 4 cups water. Stir well.
Fill glasses with ice and then pour the blueberry lemonade into the glasses, scooping some of the soften blueberries.