Preheat oven to 375°F. On a lightly floured surface, roll pastry into a 12-inch round. Fold pastry circle into fourths and transfer it to a 9-inch pie pan. Unfold and ease pastry into pie pan without stretching.
Trim pastry to ½ inch beyond edge of pie pan. Fold under extra pastry even with the pie pan edge. Crimp edge as desired. Prick bottom and sides of pastry with a fork. Bake 15 minutes or until golden. Cool on a wire rack.
Meanwhile for filling, in a large saucepan, stir together granulated sugar, cornstarch and orange zest. Stir in orange juice and water until smooth. Add 5 cups blueberries. Cook and stir over medium heat until thickened and bubbly; cook and stir for 1 minute more. Remove from heat. Stir in 5 more cups blueberries. Spoon filling into pie crust, then top evenly with remaining 2 cups blueberries. Refrigerate for 4 to 24 hours. Before serving, sprinkle with coarse sugar, if desired.