in medium sauce pan drain slam juice and st the clams aside

combine clam juice with onion, celery and potatos

add enough water to barley cover and simmer, covered, over medium heat until potatos are tender (about 20 min)

in large saucepan melt butter

add flour and stir with butter

slowly whisk in the warm half and half

cook and whisk until smooth and thick, 5 minutes

add the vegetables with there cooking liquid , clams, salt, pepper and sugar