Preheat oven to 350°F. Grease a 9 x 9 inch baking pan. (If you use an 8 x 8 inch pan, it will take longer to cook, in the middle.)
In a large mixing bowl, beat together butter and sugars; add eggs, one at a time, and beat, until mixture is light and fluffy. Stir in peanut butter, vanilla, and water.
In a separate mixing bowl, mix together flours with salt, baking powder, and baking soda. Stir into peanut butter mixture, and blend well. Fold in peanut butter chips. Spread batter into the prepared pan.
Bake for 30 to 35 minutes, or until the top springs back, when touched. Cool, and cut, into 16 squares.