THESAURUS
spillway
aqueduct, arroyo, bed, canal, creek bed, culvert, donga, dry bed, flume, gulch, gully, gullyhole, headrace, irrigation ditch, nullah, race, river bed, riverway, runnel, sluice, spillbox, stream bed, streamway, swash, swash channel, tailrace, wadi, water carrier, water channel, water furrow, water gap, water gate, watercourse, waterway, waterworks