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Outdoor sewage spills pose a serious threat to people and the environment because of the harmful pathogens they contain.  In the event of an outdoor sewage spill:

  • Take immediate action to minimize the damage.
  • Keep pets and children away.
  • Protect yourself and others to avoid contact with the sewage.
  • Before dealing with the sewage, wear protective clothing to protect yourself against harmful bacteria, viruses and parasites.

It is never a convenient time to experience an outdoor sewage spill, but what matters the most is how you act. This clean-up guide covers how to:

  • Practice proper hygiene
  • Clean up the spillage
  • Restore contaminated materials
An outdoor sewage spill. Photo by Public Health - Seattle & King County
An outdoor sewage spill.
Photo by Public Health — Seattle & King County.

Practice proper hygiene

The ideal way to protect yourself from contamination is to wear rubber gloves, rubber boots, a waterproof bodysuit, goggles and a mask. Chances are you might not have all these protective items on hand. So, do your best to cover yourself with what you have. Things like sunglasses, jeans, a long-sleeved jacket or a rain jacket, gardening gloves and waterproof hiking boots offer some protection. For extra protection, cut head and armholes in a large plastic trash bag and wear the bag over your clothing.

Once the clean-up is complete, it is best to throw away the clothes you were wearing. If you are keeping them, make sure you wash them separately on a hot wash setting (60°C). Other things you should bear in mind when you are in close contact to raw sewage are:

Dress for proper hygiene when managing a sewage spill clean-up.
  • Avoid eating or drinking when in the same location as the contaminated area. Sewage has very harmful microorganisms that can enter the body if the necessary precautions are not followed.
  • Wash your hands after every encounter with the sewage.
  • Cover up any cuts or grazes to prevent them from coming into direct contact with the sewage.

Clean up outdoor sewage spills

Secure and prepare the area

  • Isolate the entire affected area. Keep children and pets away! To avoid any illness or further contamination, it is important not to let your children and your pets near the affected areas.  This may be difficult, especially if you have young children who want to go outside and play and/or you have pets that need to go outside regularly.  
  • Turn off the water supply as soon as possible to reduce sewage from being pumped out.
  • Immediately remove all movable items or objects that can be disinfected at a later date, such as garden furniture, toys, washing line props, pegs, etc.

Clean up small spills

Clean small sewage spills – less than 10 gallons – using garden lime or a wet/dry shop vac or by calling an environmental waste clean-up company.

Most garden shops sell garden or agricultural lime. This is an excellent and recommended substance that reduces the sewage odour and encourages the breakdown of organic matter.

If the sewage spill is minor:

  • Liberally sprinkle garden lime over the spill to absorb the sewage until the affected area is covered in a white dust.
  • If the sewage is thicker in certain areas, mix the lime in to help it work better. Use a rake or spade to do this.
  • Let the lime covered areas stand for 24 hours.
  • Once the lime is dry, shovel the sewage-contaminated lime into doubled heavy-duty trash bags.
  • Wash the remnants of dried lime away from the ground with a garden hose.
  • Use a hose, sprinkler or watering can to water over the area (depending on how large it is).
  • Let the area dry out in the sun for a day. Sunlight helps kill bacteria so don’t rake the affected area straight away as this can slow down the process.
  • If you still see white dusting of the lime, water over it again until it disappears.

If the sewage spill is major (or there is a lack of sun, perhaps in the winter months):

  • Contact an approved pumper truck or a sewage clean up company that can collect the liquid sewage. Huge amounts of liquid can be extracted from the ground using a vacuum tanker. 
  • Solid waste and debris that is left behind needs to be removed by hand and placed into bin bags and then into the garbage.

*Reminder: Children and pets must be kept away from the contaminated area throughout the whole clean-up process as lime and bleach can be as harmful as the raw sewage itself.

Contaminated areas, materials and objects

After sewage clean-up, the contaminated items need to be disinfected. Act as quickly as possible, as the longer objects are contaminated, the higher the risk of further contamination.

  • Driveways, patios, decking, ornaments, tables, benches and other garden furniture or hard surfaces should be scrubbed clean with hard bristle brush, using hot water, bleach and soap. Water needs to be as hot as it can be (use gloves to help withstand the heat)
  • Anything that has encountered the sewage in a small amount can be washed on a hot wash or can be taken to the dry cleaners. Do not mix items with non-affected clothes). Do not use bleach on grass, dirt or other natural surfaces. Call an environmental waste clean-up company, a Septic Tank Company and have them come out and disinfect the area.

Finally, if you were using the land to grow crops, you will need to stop growing anything on the land for the following 12 months.