Water eductor

It consists of a large bore straight tube to which is attached a hose pipe through which clean water is pumped.

Using a water dredge or airlift, the underwater archaeologist has an advantage over terrestrial counterparts, as the spoil is removed without effort and without needing to be transported across other parts of the archaeological site.

Where there is a possibility of small artifacts being missed because of poor visibility, a trap may be used at the outlet so that the lifted sediment can be filtered.

Using the water dredge to directly suck sediments means that archaeological information on context and stratigraphy is not recorded.

An eductor can also form part of a wet scrubber system which are designed to remove soluble gases and particulate by inducing a gas flow using high pressure liquid focused into a venturi throat.