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Please read the criteria below before filing a complaint about rat problems. To file a complaint about rat infestations, rats in toilets or rats associated with illegal dumping of garbage and solid waste you can call us at 206-263-9566 or write us through Environmental Health's online services portal.

  • Rats in toilets:
    Public Health investigates complaints about rats in toilets. Investigators may follow up on your complaint by inspecting sewers near your residence, and baiting them if evidence of rats are seen. Learn more about the Seattle Sewer Baiting Program.

  • Rodent complaints:
    In the City of Seattle, Public Health responds to complaints about rodent (rats and mice) infestations and neighborhood rodent issues. We can provide information to the property owner about rodent control and enforcement of the King County Board of Health Title 8 requirements for rodent control. City of Seattle residents can report illegal dumping of garbage and solid waste on private property where rats have not been sighted to the Seattle Department of Planning and Development online or by calling 206-615-0808.

  • Homeowners and general questions about rats and rodent control:
    If you are a homeowner and are having a rat problem please read our website for information about rodent prevention and control for homeowners and tenants below. Public health cannot come to your home to eliminate rats.

King County residents outside the City of Seattle

  • Public Health does not respond to complaints about rat infestations outside the City of Seattle limits where there the complaint is not directly associated with illegal dumping or accumulations of garbage and solid waste. This includes rat complaints where the problems are due to wildlife feeding, overgrown vegetation, unmaintained property, or rat infestations inside buildings. For other cities and towns in King County, please contact your local Code Enforcement office. See list of links to cities and towns in King County then conduct a search for Code Enforcement on their websites.

  • When there is an accumulation of garbage, solid waste or illegal dumping on a property a complaint can be filed with public health. Public Health will investigate the illegal dumping or garbage storage based on the implementation of our solid waste regulations. Visit our illegal dumping page for more information about accumulations of garbage, solid waste and illegal dumping.

  • If you are a homeowner and are having a rat problem please read our website for information about rodent prevention and control for homeowners and tenants below. If you are a tenant you may want to call your city or county code enforcement office.
  • Under wood piles or lumber that is not being used often
  • Under bushes, vines and in tall grasses that are not trimmed or cut back
  • Under rocks in the garden
  • In cars, appliances and furniture that has been put outside and is no longer being used
  • In and around trash and garbage that has been left on the ground
  • In holes under buildings
  • In the insulation of walls or ceilings
  • Inside the crawl spaces
  • Behind or under cupboards, counters, bathtubs and shower stalls
  • Near hot water heaters and furnaces
  • In basements, attics and wherever things are stored in boxes, paper or cloth
  • Garbage that rats can get into, like garbage cans with loose lids, plastic or paper bags, and litter.
  • Food for pets and birds that has not been eaten. Birdseed on the ground, pet food in pet dishes, bread crumbs, etc.
  • Fruits and berries that have fallen to the ground.
  • Compost pile or worm bin that isn't taken care of the right way (do not put meat, fish, poultry, or dairy in the compost)
  • Dog droppings

Do not give food and shelter to these most unwanted guests!

  • The time to act is before the signs (droppings) of a rat or mouse.
  • Stack fire wood 18 inches off the ground and away from all buildings.
  • Birdhouses and seed should be on poles and in trays rats can't get.
  • Keep garbage can lids closed tightly.
  • Plant bushes so they will stay at least 3 feet from your house.
  • Keep yards and alleys clean. Take junk to the dump!
  • If you feed them, they will stay. Pick up fruit and vegetables in your yard.
  • Do not compost any animal products (fish, meat, chicken, cheese, butter). Keep lids tight.
  • Use only rodent resistant composters.
  • In basements keep any food in closed containers that rats can't chew through.
  • Cover all openings to your house. Rats can get into very small places.
  • Do not leave your pet food outside. If your pet doesn't eat it, the rats will.
  • Roof rats get into your house from tree branches that hang over the roof. Keep trees cut back and cover any openings in the eves.

Rats live in sewers and can follow the food in pipes up to your toilet.

  • Keep your kitchen sink rinsed clean and use garbage disposals as little as possible.
    • Rinse out your kitchen sink once or twice a month.
    • Use 1 cup of bleach (an alternative to using bleach, 1 cup of baking soda followed by 1 cup of vinegar) and rinse with boiling water.
  • Never throw grease down the drain.
  • Keep your toilet lid down when not in use.
  • If you find a rat in your toilet, flush it! (hint: squirt a little dishwashing liquid under the lid into the bowl, wait a couple of minutes then flush.)
  • Learn more about the Seattle Sewer Baiting Program.

The best trap is the large, simple, cheap wooden "snap trap." They are sold in hardware stores.

To use the trap:

  • BAIT IT with pieces of apple, potato, raw bacon or with peanut butter spread on a cotton ball. Make sure the bait is attached to trap.
  • ATTACH IT firmly to the ground or solid place to keep the rat from dragging the trap away.
  • PLACE THE TRAP near where you have found the droppings. Make sure the trap is safe from people, children, pets or animals who could get hurt from it.

Poisons are not recommended for rat control inside buildings, since poisoned rats can die in hard to reach places causing a very bad smell. When poisons are used, they must be secured (such as in a bait station) so that they are not available to children, pets or non-target animals. They must also be used in accordance with the directions on the label. For additional information, see also the WA Pesticide Control Act (Chapter 15.58 RCW), the WA Pesticide Act (Chapter 17.21 RCW) and the Rules Relating to General Pesticide Use (Chapter 16-228 WAC.)

DEAD RATS must first be wrapped in newspaper, or placed in a plastic bag before putting it in a tightly covered garbage can. Injured or sick rats must be killed, then wrapped and put in the garbage can. Try not to touch the dead rat. Use gloves if possible.


If you are cleaning out a building that has been closed up, such as a cabin, shed, or garage, or areas where rodent nesting material have been found, follow these steps.

  1. Air out the building for at least 30 minutes by opening windows and doors. Leave the building while it is airing out.
  2. Wear rubber, plastic, or latex gloves. A dust mask may provide some protection against dust, molds, and insulation fibers, but does not protect against viruses.
  3. Mix a solution of 1 cup bleach to 10 cups water or use a household disinfectant
  4. Don't vacuum, sweep or dry dust areas when cleaning. This disturbs dried rodent urine and feces that may contain harmful bacteria and viruses.
  5. Wet down all contaminated areas, dead rodents, droppings and nesting areas with a disinfectant before cleaning. Allow the disinfectant to set for 10 minutes.
  6. Disinfect counter tops, cabinets and drawers, floors and baseboards.
  7. Steam clean carpets, rugs, and upholstered furniture.
  8. Dispose of dead rodents and contaminated items by double bagging in plastic bags and placing in your garbage can outside.
  9. Wash clothes and bedding in hot water and detergent. Set the dryer on high.
  10. When you are done, disinfect or throw away the gloves you used. Wash your hands or shower with soap and hot water.


Rodents, including squirrels, mice, and rats, may construct their nests in cars, trucks, campers, and other vehicles, especially if such vehicles are used infrequently. Rodent nesting materials can be found in many areas of a vehicle:

  • the engine compartment, including in engine compartment insulation;
  • the ducting and air filtration components of a vehicle’s heating and air conditioning system;
  • the trunk of a car, including the spare tire compartment;
  • the passenger compartment, including the headliner, glovebox, and in or under the seats;
  • tool compartments; and,
  • taillight and headlight access areas and enclosures.

Some rodents, such as deer mice, can carry hantavirus, and their nesting materials, droppings, and urine may contain hantavirus. People cleaning or riding in the car may be in contact with these infected materials. Infectious virus particles blowing onto passengers through the air vents may pose a risk to people who use the vehicle.

Rodents can enter vehicles through:

  • rust holes,
  • wire chases,
  • side vents,
  • rocker panels, and,
  • ducting

An accumulation of nesting materials in the air intake system of a vehicle can also contribute to odors inside the passenger compartment, and could potentially impair engine performance, preventing the vehicle from starting, or causing it to run poorly. (These problems may also be caused by electrical wires and cables that the rodents have chewed on.)

Preparing to inspect, detect, disinfect and remove potentially infectious nesting materials from a vehicle

Engine compartment

While the car is in open air, open the hood to allow the engine compartment to air out for 20 minutes. Also, open vehicle doors and the trunk to facilitate airing out. Wearing plastic gloves and a long-sleeve shirt, inspect the engine compartment for evidence of nest building. Accumulations of nesting materials could occur anywhere but frequently occur between the battery and vehicle frame, in the area near the windshield wiper motors, or underneath air intake ducting or within the air filter.

Areas of the vehicle with evidence of rodent activity (e.g., presence of dead rodents, droppings, or nesting materials) should be thoroughly disinfected and cleaned to reduce the likelihood of exposure to hantavirus-infected materials.

To avoid generating potentially infectious aerosols, do not use a vacuum cleaner or sweep rodent urine, droppings, or contaminated surfaces until they have been disinfected. Also, do not use ‘power wash’ high-pressure sprayers to soak or dislodge nests or droppings.

First, remove the cables from the battery, to reduce the likelihood of getting shocked while cleaning out the nesting material. Then, using either a commercially labeled disinfectant or a mixture of 1 part bleach to 9 parts water, spray the materials until fully soaked and let sit 5 minutes, or follow the manufacturer’s instructions for dilution and disinfection time. Then, use a paper towel to pick up the materials, and dispose of the waste in the garbage. After the rodent droppings and nesting materials have been removed, clean the rest of the area with additional disinfectant. When the recently-sprayed area is dry, reconnect the battery.

Nesting materials within automotive air intake systems

Rodents may travel through the vehicle’s air intake system, building nests on top of accordion-style air filters or in hoses and ducting leading directly to the passenger compartment. For engine compartment air filters, open the unit to reveal the filter. If you see evidence of rodent activity, spray as above using either a commercially labeled disinfectant or a mixture of 1 part bleach to 9 parts water. Spray the materials until fully soaked and let sit 5 minutes, or follow the manufacturer’s instructions for dilution and disinfection time. Then, remove both the nesting materials and the air filter, and discard in the garbage. Insert the new replacement filter, and close the unit.

Inspection, disinfection, and possible replacement of hoses, ductwork, other filters, fans, or other components of the system may be necessary if the rodent infestation is extensive, and should be carried out by qualified mechanics or automotive professionals, using appropriate precautions. Advise the mechanic of the potential for hantavirus.

Passenger compartment

Rodents can enter the passenger compartment through ducting, through rusted areas, through areas where cabling passes, and from the trunk. A variety of approaches can be used to seal out holes and cracks where rodents can enter, depending upon the materials available. Do not leave any kind of food anywhere in the car, as it can attract rodents.


Rodents can enter the trunk from holes in the body, through cable conduits, and from the back seats in certain vehicles. A variety of approaches can be used to seal out holes and cracks where rodents can enter, depending upon the materials available. Do not leave any kind of food anywhere in the car, as it can attract rodents.

After inspection and cleaning

Before removing your gloves, rinse your gloved hands with disinfectant, empty the remaining disinfectant in the garbage bag containing the disposed material and seal the bag. Rinse your gloved hands with water, removed your gloves and terminate the process by washing your hands with soap and water.

Prevention of colonization of vehicles

Regular exterior and interior inspection of a vehicle, whether in regular use, abandoned, or garaged for the season or otherwise stationary, will help prevent colonization or infestation of a vehicle. Snap traps and poison baits are effective in stopping rodent access into vehicles. When starting a vehicle that has been idle for an extended period, air it out first, and inspect the air intake and filters before starting the engine.

For more information on cleaning up after rodents, see:

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For heavy rodent infestations (piles of feces, numerous nests or dead rodents), Public Health recommends consulting a professional pest company.

Watch a video on how to prevent rats from getting into your home and what to do if you find rat droppings.

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