These two videos demonstrate a phenomenon called the “Floating Water Bridge”.

See also: High Voltage Water bridges

The bridge can stretch up to about an inch.

To create the bridge you start with two containers of deionized water. You add electrodes (visible in the second video) and apply 10,000 to 15,000 volts DC between the two containers. The water has to be deionized. If you add a little salt (and hence ions) to the water, the bridge doesn’t work.

The water in the bridge does heat up, and shown by a themographic camera:

According to This article the bridge forms because of a microstructure inside the charged water:

The group’s analyses have shown that the explanation may lie within the nature of the water’s structure. Initially, the bridge forms due to electrostatic charges on the surface of the water. The electric field then concentrates inside the water, arranging the water molecules to form a highly ordered microstructure. This microstructure remains stable, keeping the bridge intact.