Place chicken and water in a large kettle or Dutch oven; bring to a boil. Reduce heat; add onion, celery, bouillon, parsley sprigs, garlic and salt if desired. Cover and simmer until the chicken is tender, about 1 hour. Remove chicken; allow to cool. Strain and reserve broth; discard vegetables. Add carrots to broth and simmer until tender, about 15 minutes. Debone chicken; cut into cubes. Add chicken and chopped parsley to broth; heat through. Ladle into bowls; add rice to each bowl.