Hydrant paint schemes are unlimited. In some water systems, paint colors show water flow capacity of the individual hydrants. In others the color is chosen to aid visibility of hydrants, or to fit into the local landscape, or even to salute the local sports team.

In modern dry barrel hydrants, an automatic drain valve opens briefly as the main valve opens using main pressure to force flush any debris from the drain channels, and to establish water flow into the surrounding soil, or drain field. Once the hydrant opens fully, the drain closes to prevent water escaping while the hydrant is in operation. When the hydrant is closing, the drain opens again and remains open to allow water drainage from the top of the hydrant. Not all dry barrel hydrants have drains, however, as soil or high ground water conditions may dictate they be plugged or not installed. As part of the annual inspection of such hydrants, a portable pump is used to remove any remaining water before winter.

In warm climates where freezing does not occur, the