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Cleanups and wastewater controls alone are not enough to protect the Duwamish in the future – we all have a responsibility to do our part to prevent harmful chemicals from getting into our waterways.

The Duwamish Waterway has historical sediment contamination from past development practices. Once it is contaminated, it is hard and expensive to clean up. Collectively, utility rate payers and tax payers (all of us) will need to invest millions of dollars in a plan to clean it up.

Preventing pollution takes effort but it is cheap and effective. You decide...

Fish advisory sign

In the Duwamish, the greatest risks to people today come from eating flatfish, perch, crabs and clams. Lower risks are linked to direct contact with sediments (river mud) – from clamming, tribal net fishing and public breach play. There are also risks for animals such as river otters, and worms and invertebrates in the mud. Fish advisories are posted, advising no consumption of resident local fish, with exceptions (see below).

According to the Washington State Department of Health the main pathway for exposure to contaminants in the Lower Duwamish Waterway is through seafood consumption.

How to reduce exposure to contaminants in Duwamish seafood
  1. Do not eat any crab, shellfish, or fish (the exception is salmon) from the Lower Duwamish Waterway.
  2. Salmon from the Lower Duwamish Waterway are safe to eat
    View the Washington State Department of Health Fish Consumption Advisories for Duwamish River.
Recommendations to reduce exposure to contaminants in Duwamish sediments

Although according to the Washington State Department of Health the main pathway for exposure to contaminants in the Lower Duwamish Waterway is through seafood consumption (above), soils and sediments at public access areas along the river may also contain PCBs and other toxic contaminants.

Recommendations to lower your exposure at Lower Duwamish Waterway beaches

Although health risks from recreational activities on the Lower Duwamish Waterway beaches are relatively low, common sense approaches can reduce exposure to contaminants.

  • Keep clean:
    • If you go to the beach, wash your hands and face with soap afterwards, especially before eating.
    • Clean dirt from under your nails.
    • Wash soiled clothing separately.
    • Young children are especially sensitive to contaminants. Remember to wash your children's hands, toys, and pacifiers.
    • Keep pets clean.
  • Avoid bringing contaminants home
  • Stay in public use areas
  • Swimming in the Lower Duwamish Waterway:
    • You can swim in the river, but be aware there are several combined sewer overflows (also known as CSOs) that can discharge waste water into the waterway during periods of heavy rain. King County has CSOs in the LDW. The agency Public Health-Seattle & King County recommends against swimming near combined sewer overflows for a period of 48 hours (two days) after the last heavy rain in case CSO has discharged.... If you wish to know if a CSO has discharged, King County provides service to learn if a CSO has discharged...
For more information
Keep cars maintained; fix leaks

WHY? Vehicles can account for a lot of air and water pollution, but less so if they are well-maintained.

HOW? Maintain with regular tune-ups and fix fluid leaks. Recycle used oil and dispose of oil filters and antifreeze properly. Never pour anything but clean water down a storm drain, since most drains go straight to streams or rivers. Get vehicle-emission checks in designated areas. Close the loop by using re-refined oil. Wash your car at an approved commercial car wash. If you do wash it at home, park it on gravel or grass and use a shut-off hose nozzle and phosphate-free soap. Keep litter bags in the car and use them. Learn more about how to protect Washington Waters .

Better yet, take the train, plane or bus.

Related information 

Car Maintenance Toolkit , Washington State Department of Ecology

Put trash in a trash can, not the toilet
Put trash in a trash can, not the toilet

Why put trash in a trash can, not the toilet? Trash, hair and grease in the sewer pipes create overflows which can harm human health and the Puget Sound. Wastewater treatment plants use natural processes to turn dirty water into clean water and fertilizer before it is returned to the environment. Not all chemicals found in medicines, cleaners and personal products can be removed during treatment.

How to dispose of trash properly:

  • Don't put grease, fats, or oil of any type down your drain or garbage disposal.
  • Think trash not toilets. Flushing the wrong thing down the toilet damages your household plumbing, your environment and the wastewater treatment system. If it isn't biodegradable, put it in the trash instead of the toilet.
  • Choose natural, simple, biodegradable products and help keep chemicals out of our environment. Nothing disappears – drains and toilets are the first step to a clean Puget Sound.
Pick up pet waste and throw in trashcan

Pick up pet waste and throw it in a trashcan.

Why properly dispose of pet waste? Pet waste can be a health risk to pets and people, especially children. Pet waste is full of bacteria that can make people sick. Unless properly taken care of, pet waste and its bacteria is washed by rain into our storm drains, and is carried into our waterways without treatment. This waste can get into shellfish, potentially making people who eat shellfish sick.

How you can get rid of pet waste and help keep our waters clean: Scoop it up, seal the waste in a plastic bag and throw it in the garbage. (Be sure that this is legal in your area.) You may also bury small quantities in your yard where it will decompose slowly.

Choose natural, simple products. Avoid fragrances, phosphorous and chemicals.
Choose natural, simple products

Choose natural simple products. Avoid fragrances, phosphorus and chemicals.

Why? Choosing environmentally friendly, biodegradable household cleaning and personal care products minimizes the entry of harmful chemicals into the wastewater stream and the environment.

Tips on finding the safest household products
  • Look at the warning words on the label. The warning words "Caution" and "Warning" indicate a moderate hazard. The words "Danger" and "Poison" on the label indicate highest hazard. Avoid products marked "Danger" or "Poison" and look for products with no warning words. Note that particular warning words don’t always refer to the same kind of hazard.
  • Chose a product with no scent or a mild scent. Scented products can add chemicals to the indoor air environment and may be disruptive to children and to people with respiratory ailments or sensitive skin.
  • Check the product’s ingredients. Finding out what’s in a product can sometimes be difficult because manufacturers aren’t required to list all the ingredients (except for food products).
  • Follow the instructions for product use. Information on the product label tells how to properly use the product, how to store it and clean it up, and how to avoid water pollution and environmental harm.
Use or Make Safer Alternatives

Safer alternatives can be substituted for many products that contain hazardous ingredients, particularly for products used to clean drains, toilet bowls, ovens, bathtubs and tiles. Learn more by visiting the Local Hazardous Waste Program in King County.

Reduce fertilizers and pesticides: choose natural yard care.

Reduce fertilizers and pesticides; choose natural yard care.

Why reduce fertilizers? Fertilizer isn't a problem - if it's used carefully. If you use too much fertilizer or apply it at the wrong time, it can easily wash off your lawn or garden into storm drains and then flow untreated into waterways.

How can you fertilize and help keep our waters clean? Use fertilizers sparingly. Many plants do not need as much fertilizer or need it as often as you might think. Don't fertilize before a rain storm. And consider using organic fertilizers; they release nutrients more slowly.

For more information on fertilizing alternatives: Contact the Washington State University Extension King County Master Gardener Program

From your house to the river - how the Duwamish gets "dirty" From your house to the river - how the Duwamish gets "dirty" , August 2009

Our DuwamishThe Lower Duwamish Waterway is an economic engine, cultural icon, and vital regional transportation corridor. No matter where we live in King County, no matter how we use the river, we all have a stake in protecting it -- it’s Our Duwamish.