Place a rack in the middle of your oven and preheat it to 350°F. Grease 2 loaf pans with butter. In a medium bowl, mix the sifted flour, baking powder, baking soda, salt, and pumpkin spice.
In a large bowl, mix the pumpkin puree, sugar, oil, eggs, vanilla, and water.
Add the dry ingredients on top of the wet ingredients.
Mix the dry ingredients lightly into the wet, just until a batter forms. Small lumps are ok.
Split the batter between the two greased loaf pans and smooth the top.
Bake for about an hour, or until a knife inserted into the crack in the loaf's top crust hits the bottom of the pan and comes out clean.
*While sugar is technically a dry ingredient, in some types of batters (like cake and quick bread batters), it is treated as a wet ingredient. Dissolving the sugar in the wet ingredients helps to weaken gluten-forming proteins, so you don't get chewy pumpkin bread.