In a large pot, bring water to a boil and add salt. Cook the rotini pasta according to package instructions until al dente. Drain and rinse under cold water to cool.

In a large mixing bowl, combine the cooled rotini with cucumber, carrot, onion, bell pepper, olives, and parsley. Toss until evenly mixed.

In a mason jar or bowl, blend Greek yogurt, red wine vinegar, lemon juice, garlic, onion powder, oregano, and dill. Shake or whisk until smooth. Adjust consistency with water if necessary.

Pour the tzatziki dressing over the pasta mixture and gently toss to coat evenly.

Cover and refrigerate the salad for at least one hour to let flavors meld before serving.