Set a 6-qt stock pot on stove, add bacon and brown over medium heat. If substituting a low fat bacon like Canadian bacon, add 1 tablespoon canola oil. Add diced onions and cook until tender and golden. Stir in flour and cook 2 minutes. Gradually add preheated water and clam juice, including reserved clam juice. Stir in potatoes and add thyme, bay leaf, pepper, and celery seed. Cover, bring to a boil, reduce heat and simmer about 20 - 25 minutes until potatoes are tender.
Meanwhile, in a separate 1 quart pot heat 2 tablespoons canola oil over medium heat. Stir in 1/4 cup flour and cook about 2 minutes, do not allow flour to brown. Gradually add preheated milk. Use a whisk to eliminate any lumps, continue heating until mixture begins to boil and thickens.
To the broth and potato mixture in the stock pot, stir in the minced clams. Cook for 3 minutes. Add milk mixture and stir until uniformly mixed. Remove from heat, add chopped parsley, and serve.