Bailer

A bailer is a device used for removing water which has entered a boat. In the simplest case it is simply a container which can be filled manually and tipped over the side.

By extension a bailer is also a hollow plastic tube used for obtaining water samples. Although widely used due to their ease of use and low cost, they have several disadvantages. In groundwater monitoring applications, bailers may cause aeration of both the sample water and the water within the well casing. Bailer usage may also increase the turbidity of a sample. Large amounts of suspended solids in the sample water can prevent the check valve from operating correctly, sometimes resulting in sample loss.

Bailers are tied to a piece of rope(usually made from nylon or polypropylene) or a piece of wire (composed of Teflon or stainless steel) and lowered into the water column.

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