Homemade Watermelon Lemonade

14 to 16 small lemons or 10 to 12 medium lemons1 cup sugar (or equivalent in artificial sweetener, or a 50/50 mix of the two)3 cups watermelon chunks, seeds removed and pureed in a blender or food processor3 cups cold bottled waterPinch of saltScrub lemons well under cold running water and blot dry with paper towels. Slice lemons in half from tip-to-tip, then cut crosswise into thin slices and place in a large, high-sided stainless steel saucepan or glass bowl. Sprinkle with sugar.Using a potato masher or large spoon mash lemons with sugar until they give up their liquid and sugar dissolves, about 3 to 4 minutes.Using either a stainless steel colander or wire mesh strainer, place half lemon mixture in a strainer and strain, pressing on the solids, into a large glass bowl. Discard what remains in the strainer and repeat with remaining lemon mixture.To the bowl, add pureed watermelon, water, and stir together until combined. Refrigerate until well chilled.Serves six to eight.Nutrition values per cup (made with sugar): 145 calories (2 percent from fat), 0.3 g fat (0 saturated), 39 g carbohydrates, 0.5 g fiber, 0.4 g protein, 0 cholesterol, 45 mg sodium.Leannote: Substituting artificial sweetener for all the sugar reduces calories per cup to 40 and carbohydrates to 10.8 g.