How Can I Manage Fire Water Run-Off?

Following on from our previous blog on the importance of managing fire water run-off (click here for a reminder), this blog will focus on management strategies.

Risk Assess

Contaminated fire water can cause environmental pollution and could potentially lead to prosecution or fines, so it is essential that you have a strategy to manage the risk and include it in your emergency plans and procedures.  When considering your strategy, you should carry out a risk assessment that should be comprehensive and include factors like:

  • The volume of water that might be used to tackle a fire
  • The substances you store on site and what the fire water could become contaminated with
  • Pathways of how fire water could enter the environment e.g. surface water drains, foul drains, direct run-off into watercourses or absorption through the ground
  • The sensitivity of the environment that would be affected by contaminated fire water
  • Current site arrangements that could deal with fire water run-off

After these assessing these considerations, it is important to determine whether additional measures are required to sufficiently manage fire water run-off.

Fire Water Containment

To prevent fire water from causing pollution, containment is the best method.  There are various methods of containment, permanent or temporary, including:

  • Containment lagoons e.g. earth banked containment basins
  • Purpose built or portable tanks, overdrums and tankers, where contaminated water can be contained
  • Shut-off valves and penstocks where the whole or part of the drainage network can be isolated to contain contaminated water (read our next blog for more information on this)
  • Sacrificial area that can be used for other purposes like a car park or sports ground when there is not an emergency
  • Bunding of vehicle car parks and other hard standing areas
  • Pits and trenches, where no other option is available around the site

In all cases, fire water must be fully contained.  This may mean installing an impermeable membrane or a method of isolating the drainage network in a particular area.  In addition, some of these methods may allow the recycling of fire water if a risk assessment determines it is possible.

Other methods of fire water management

It is not always possible to provide containment for fire water, but the options should always be assessed and considered.  The main concern is ensuring that fire water does not enter drains.  This can be avoided by using suitable spill kits or drainage covers to protect them.  If this method is used, be sure to dispose of the waste correctly.

As part of your emergency procedure preparation, you must consider fire water management.  When you have a suitable strategy, you should ensure this is included in your PIRP and other procedures.  You should make sure the necessary equipment is available and that everyone is aware of your procedures.  You should ensure any waste and contaminated water is disposed of legally and that you fully check all drains and interceptors for contamination before opening drainage systems after the event.