The affected fire and rescue service will need to liaise with the local water authority to identify suitable hydrants, taking into account the water flow and size of main. Hydrant information may be available from fire and rescue service water managers and on fire appliance mobile data terminals (MDTs). If possible, ensure the hydrant main selected is not already being used for firefighting activity, or that by connecting into it the HVP it doesn’t affect the water supply to properties in the area.

The methods of setting up high volume pump (HVP) equipment from a pressure-fed water supply are detailed in National Resilience procedural information and include:

• Submersible pump at the hydrant
• No submersible pump
• Submersible in the hose line

A non-return valve will always be used next to the hydrant, to protect the water main. Where HVPs are pumping from open water and pressure-fed supplies at the same incident, water circuits should remain separate to avoid the possibility of cross contamination of mains water supplies. Hydrant pits and standpipes should be coned off and lit, particularly during the hours of darkness.

The distance from the hydrant to the incident should be measured, and a suitable hose deployment route identified. Each HVP hose set holds 3 kilometres of 150mm hose in 50m lengths. One length of HVP hose holds approximately 1,000 litres of water when charged, and weighs approximately one tonne.

The HVP equipment, including the HydroSub if required, should be located in an area that has been made as safe as practicable.