Stir in the flour, salt, baking powder. Fold in the blueberries.
Spread the blueberry batter evenly in two greased loaf pans. Set aside.
For The Topping
Melt the butter in the microwave or on the stove top. Let the butter cool for a short while until it is cool enough to touch and you can mix it into the streusel mix with your hands.
Mix the flour, sugar brown sugar and cinnamon together in a small bowl.
Pour the butter in the streusel mixture and mix with either a fork or your hands until it is all mixed together and crumby.
Sprinkle over the blueberry batter.
Bake in a 375* oven for 50-60 minutes or until toothpick inserted into the center comes out clean.
Remove from oven and turn out onto a cutting board after 15 minutes.