Preheat oven to 350°F. Place flour, sugar, baking soda, spices, and salt in a mixing bowl and stir to combine. In a second bowl, beat eggs, pumpkin, oil, and water with a hand mixer until fully combined.
Make a well in dry ingredients. Pour in wet ingredients and mix with a wooden spoon until just combined (be careful not to overmix) and then fold in walnuts. Pour batter into greased and/or lined loaf pan.
Bake for 65-70 minutes or until a toothpick inserted in the center comes out clean. Remove from heat and let cool in the pan for 15 minutes, then turn out onto a rack to cool completely.