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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
  • Keep children and pets away
  • Avoid direct contact with sewage
  • Wear protective clothing

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

It is important to avoid any direct contact with sewage since sewage contains very harmful microorganisms that can enter the body if precautions are not followed.

Protect yourself from contamination by wearing rubber gloves, rubber boots, a waterproof bodysuit, goggles and a mask. If you do not have all of these items on hand, use items such as sunglasses, jeans, a long-sleeved jacket or a raincoat, gardening gloves, or waterproof hiking boots for protection. For additional protection, wear a large garbage bag over your clothing. After clean-up, throw away protective items and clothing or, if you choose to keep them, wash separately on a hot wash setting (60°C).

Other things to keep in mind when in close contact with raw sewage are:

Dress for proper hygiene when managing a sewage spill clean-up.
  • Avoid eating or drinking when in or around the contaminated area.
  • Wash your hands after every encounter with sewage.
  • Cover any cuts or grazes.

Clean up outdoor sewage spills

Secure and prepare the area

  • Isolate the affected area to prevent further contamination.
  • Keep children and pets away from affected areas.
  • Turn off your water supply as soon as possible to reduce sewage pumped out.
  • Immediately remove all items or objects that can be disinfected later, such as garden furniture, toys, washing line props, pegs, etc.

Clean up small spills: less than 10 gallons

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

You can purchase garden, or agricultural, lime at most garden shops. Garden Lime reduces sewage odor and encourages the breakdown of organic matter.

If the sewage spill is minor:

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

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

  • Contact an approved pumper truck or a sewage clean up company. Large amounts of liquid can be extracted from the ground using a vacuum tanker.
  • Solid waste and debris 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 clean-up process as lime and bleach can be as harmful as raw sewage.

Contaminated areas, materials and objects

After clean-up, contaminated items must be disinfected. The longer objects stay contaminated, the higher the risk of further contamination, so act quickly.

  • Driveways, patios, decking, ornaments, tables, benches and other garden furniture or hard surfaces should be scrubbed clean with hot water (as hot as possible), bleach, and soap using a hard bristle brush. Use gloves to protect from heat.
  • Wash anything that has encountered small amounts of sewage in a hot wash or take to the dry cleaners. Do not mix affected items with non-affected clothes.
  • Do not use bleach on grass, dirt, or other natural surfaces. Call an environmental waste clean-up company or a septic tank company to disinfect the area.

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