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Stormwater Pollution

What is stormwater pollution?

Stormwater runoff is rain that falls on streets, parking areas, sports fields, gravel lots, rooftops or other developed land and flows directly into nearby creeks, rivers, lakes, and the Puget Sound. The rain picks up whatever's on the ground — including oil, grease, metals, coolants, fertilizers, pesticides, bacteria, soap, sediments, cigarettes, and small pieces of plastic. 

Although much of this pollution is not visible to the naked eye, stormwater is the leading contributor to water pollution in urban waterways in Washington state. Construction sites, industrial facilities, parking lots, and densely populated areas are responsible for flushing sediment and pollutants into our waterways.  

On any rainy day, the rain that falls on streets, parking lots, rooftops and impervious surfaces in downtown Bellingham flows into nearby Squalicum and Whatcom creeks, and into Bellingham Bay. Because stormwater is almost always untreated, it can harm or kill fish and wildlife and can degrade water quality. Stormwater carries pollutants into Puget Sound, but they don’t go away — they wash up on the beaches where our kids and pets swim and play, and contaminate our food chain.

How to prevent stormwater pollution

We all contribute to stormwater through our daily activities. 

Driving to town can contribute zinc, copper, and grease to the roadways, which is washed into streams when it rains. Fertilizers applied to our lawns and gardens can end up in the nearest storm drain after a hard rain. 

All of us have a role to play in protecting our waterways. The plants and animals of the Puget Sound need your help to prevent stormwater pollution. Here are some suggestions:

  • Wash your car at a commercial car wash, and check frequently to see it’s not leaking any fluids. 
  • Carefully follow application instructions for lawn chemicals, or research alternative methods. 
  • Compost fall leaves instead of allowing them to reach the street, where they block storm drains.
  • Watch over the storm drains near your house, and talk to your kids and neighbors about why only rain is allowed down the storm drain. 
  • Replace your lawn with native vegetation and stop using fertilizer.
  • Consider removing impermeable surfaces and replace them with a rain garden.
  • Always pick up your dog's poop immediately, and also pick up trash on your street. 
  • Contact City of Bellingham Storm and Surface Water Utility, or Whatcom County Stormwater Division, before you do an outdoor job that might impact stormwater. 
  • Look around next time it’s raining. When you follow the water, you’ll know where stormwater goes. 

Pollution Definitions

The contamination of soil, water, or air by materials harmful to the health of living beings. In the United States, pollution by businesses is regulated under a permit system. 

Natural Materials
Waste excreted by animals and people is a natural material, and isn’t generally a problem until it is concentrated in one place and not treated properly. Think about a sewage spill into a lake or a place where dog walkers don’t scoop the poop. Food processing plants use mostly natural material, but the processing of foods generates waste, too. There will be discarded food that doesn’t meet specifications or organic material in rinse water used to process fish, vegetables, and berries. Natural materials can contribute disease-causing bacteria to our waters and increase carbon loading, which decreases oxygen and makes it difficult for aquatic animals to survive.

Toxic Chemicals
Manufacturing facilities use materials and energy to make the items we use everyday, but most manufacturing processes are not closed loops and there may be water and air emissions. In Whatcom and Skagit counties, there are 4 oil refineries and an aluminum smelter. The discharges from these large industrial facilities contain complex hydrocarbons and greenhouse gases. Other manufacturing plants also contribute toxic loads to the air and water, albeit at a lesser scale.

Pollution discharges have decreased since the days of the Clean Water Act (1972) and the Clean Air Act (1970), because those laws put limits on how much pollution could be discharged by industrial facilities. 

Toxin Definitions

A volatile component of petroleum and coal tar, and a known carcinogen.

Can refer to one specific type of dioxin — 2,3,7,8-tetrachlorodibenzo-para-dioxin, the most potent carcinogen known — or a group of like chemicals with similar structures with similar properties. In addition to being carcinogenic, dioxins can also cause immune impairment, developmental abnormalities, and skin disorders. Some dioxins are classed as persistent bioaccumulative toxins.

Dioxins and Furans
A group of chemicals with similar structures, one of which is the most potent carcinogen known. These also cause skin disorders, immune impairment, and cancer. Some are classed as persistent bioaccumulative toxins.

Heavy Metals
Metals such as lead, mercury, arsenic and cadmium. These can have adverse effects on different organ systems, such as the liver and the brain. Some are classed as persistent bioaccumulative toxins.

A metal which acts as a poison at low levels on the central nervous system and brain. Mercury is most harmful as the organic complex of methylmercury. It can affect cognition and fine motor skills in developing babies. In adults, impairments will generally be seen in peripheral vision; disturbances in sensations, lack of coordination of movements; impairment of speech, hearing, walking; and muscle weakness. As inorganic mercury, it can cause damage to the gastrointestinal tract, the nervous system, and the kidneys. Mercury is classed as a persistent bioaccumulative toxin.

Petroleum Hydrocarbons
A mixture of chemicals including the polyaromatic hydrocarbons (PAHs). Some hydrocarbons and PAHs can cause cancer, cataracts, and skin irritation; damage kidneys, lungs, and liver; and impact reproductive, nervous, and immune systems. Some are classed as persistent bioaccumulative toxins.

Polychlorinated Biphenyls (PCBs)
Outlawed since the 1970s, they still persist in the environment and build up in fatty tissues. PCBs can cause skin, liver, and endocrine impacts, as well as neural and other health defects in children when exposed as fetuses.

Corrosive to eyes, skin, and respiratory tract. Higher exposures can lead to liver damage, muscle tremors, and loss of coordination.

Endocrine disruptors that can cause birth defects at low levels, especially to the developing male reproductive system.

Harms the reproductive and immune system, and causes birth defects. Extremely toxic to marine invertebrates at low levels, killing some species. In other marine invertebrates it can cause females to display male characteristics and become sterile.

Wood Debris
A byproduct of lumber and milling. During decomposition, oxygen is consumed by the microorganisms, which degrades the wood. This reduces the amount of dissolved oxygen in water and harms aquatic organisms.