Mix all the ingredients for the cucumber water in a pitcher. Refrigerate for 1 hour or longer if desired.
In a small saucepan, over medium heat, add the balsamic vinegar and crushed garlic and bring to a simmer. Let simmer for 5-10 minutes, until the sauce thickens. The texture should be thick syrup-like. Remove from the heat immediately.
Let cool slightly and then pour into a jar along with the olive oil, salt, and pepper, and shake well to combine.
In a large bowl, combine the arugula, watermelon, red onion, feta, mint, pistachios, and olives. Refrigerate until ready to serve.
Pat chicken cubes dry with a paper towel and season with garlic powder, salt, and pepper.
In a large nonstick skillet, heat olive oil over medium-high heat. Saute the chicken until no longer pink in the middle.
Remove chicken from heat and place into a mixing bowl. Add in buffalo sauce and toss to coat well.
Lay tortillas on a clean flat surface and divide chicken evenly into each. Layer with lettuce, tomatoes, shredded carrot, celery, and avocado. Drizzle with dressing and extra buffalo sauce if desired.
Fold in the ends and roll up tightly. Cut in half.
Drizzle the watermelon salad with the reduced balsamic vinaigrette and toss gently.
Serve the wrap with watermelon salad and cucumber mint water.