Bring water to a boil in a medium saucepan. Add onion, fennel seed, garlic, salt, turmeric, pepper, bay leaf and potatoes. Bring to a boil; reduce heat and simmer, covered, about 15 minutes. Add carrots; simmer 3 minutes. Add zucchini; simmer another 5 minutes, until vegetables are tender.
Remove 1 cup of the vegetables and broth and puree in a blender. Return puree to thicken soup; Add fish and wine. Simmer, covered just until fish is opaque, about 1 minute.
Remove bay leaf and serve with Italian or sourdough bread.