Hydrant Hygiene

Firefighters and municipal water departments routinely perform hydrant flushing and flow testing to keep fire hydrants operational, protect water quality, and verify adequate fire-flow capacity across a city’s distribution network.

During these tests, crews open hydrants in a controlled sequence to scour sediment, rust, and biofilm from water mains, while calibrated pitot gauges and diffusion cones are used to safely direct high-velocity water and measure pressure and flow rates.

Static, residual, and flow pressures are recorded to calculate available gallons per minute and to identify partially closed valves, pipe obstructions, or weak pressure zones that could compromise firefighting operations.

The process also includes lubricating valve stems, inspecting caps and threads, checking barrel drainage to prevent freeze damage, and color-coding hydrants based on verified flow capacity, making hydrant release and testing a critical element of municipal fire protection and infrastructure safety.