Instructions

  1. Combine half the watermelon, half the water and half the sugar in a blender; puree.
  2. Pour through a coarse strainer into a large container.
  3. Repeat with the remaining watermelon, water and sugar.
  4. Stir in lime juice.
  5. Refrigerate until well chilled, about 4 hours.
  6. To serve, stir in club soda (or seltzer) and garnish with lime.
  7. MAKE AHEAD TIP: Prepare through Step 1, cover and refrigerate for up to 2 days.