In a saucepan, combine quinoa and water. Bring to a boil, then reduce to simmer and cook quinoa for 12-15 minutes. Fluff with a spoon and cover with a tea towel. Let rest.
Dice onion, and chop celery and tomatoes into small chunks. Finely chop parsley and dill. Drain and rinse chickpeas.
In a large mixing bowl, combine quinoa with the vegetables, herbs, chickpeas, and pumpkin seeds.
Prepare the vinaigrette in a small mixing bowl by whisking together all the dressing ingredients. Pour dressing over quinoa salad and toss to combine.