Synonyms for Sluice (same or very similar meaning)
WordNet sense 1 (conduit that carries a rapid flow of water controlled by a sluicegate):
penstock, sluiceway
WordNet sense 2 (pour as if from a sluice):
sluice down
WordNet sense 3 (irrigate with water from a sluice):
flush
From the ODE community, based on WordNet
add/edit