Combine chicken, water, celery, bay leaf and salt in 3 quart saucepan. Bring top boiling; reduce heat and simmer, covered, until chicken is tender, about 25 minutes. Remove chicken from broth; cool, discard bones. Dice chicken; set aside. Strain broth; add enough milk to make 3 cups; set aside. Melt margarine in 3 quart saucepan; saute onion and celery until soft but not brown. Blend in flour; gradually stir in milk mixture. Add potatoes; simmer until tender (15-20 minutes). Stir in chicken, corn, salt and pepper; heat through. Garnish with chives.