Home Repair & Remodeling

What You Should Know About Urban Runoff Pollution

In the City of Poway, storm drains flow directly into local creeks, rivers, lakes and eventually the ocean without treatment.

Storm water pollution is a serious problem for our natural environment and affects water quality. Each day polluted urban runoff enters our creeks, lakes, and ocean untreated, leaving toxic chemicals in our waterways and trash on our beaches. Storm water pollution comes from a variety of sources including oil, fuel and fluids from vehicles and heavy equipment, and from materials such as concrete and mortar from construction activities.

The City of Poway is committed to improving water quality and reducing the amount of urban pollutants that enter our precious waterways.

Concrete & Masonry

Fresh concrete and mortar application materials can wash or blow into the street, gutter, or storm drain, posing a hazard to fish, wildlife and people. To avoid polluting:

  • Never dispose of cement washout or concrete dust onto driveways, streets, gutters, or storm drains.
  • Never wash excess material from bricklaying, patio, driveway or sidewalk construction into a street or storm drain. Sweep up and dispose of small amounts of excess dry concrete, grout and mortar in the trash.
  • Wash concrete or brick areas only when the wash water can flow onto a dirt area without further runoff, or drain onto a surface which has been bermed so that the water and solids can be pumped off or vacuumed for disposal. Don't mix up more fresh concrete or mortar than you will need for a project.
  • Protect dry materials from wind. Secure bags of concrete mix and mortar after they are open.
  • Set up and operate small mixers on tarps or heavy plastic drop cloths.
  • Protect applications of fresh concrete and mortar from rainfall until the material has dried.

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  • All paints and solvents contain chemicals that are harmful to fish and wildlife. It is especially important to prevent these chemicals from entering storm drains.
  • Keep all liquid paint products away from the street, gutter, and storm drains. Liquid residues from paints, thinners, solvents, glues, and cleaning fluids are hazardous wastes and should be disposed of properly. When thoroughly dry, used brushes, rags, drop cloths and empty paint cans (lids off) may be disposed of as trash.
  • Reuse paint thinner. Set used thinner aside in a closed jar to settle out paint particles. Then pour off clear liquid for future use.
  • To dispose of the remaining paint sludge, and any unusable thinner, call the Small Quantity Business Generator Hazardous Waste Disposal Program at 800-714-1195 for an appointment. For residential waste, please call 858-668-4702.
  • Never put flammable products such as oil-based paint or thinner down any drain or into the garbage!

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Paint Cleanup

  • Never clean brushes or rinse paint containers into a street, gutter or storm drain.
  • For oil-based paints, paint out brushes as much as possible. Clean with thinner, and filter and reuse the thinner.
  • For water-based paints, paint out brushes as much as possible, then rinse in sink.

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Paint Removal

  • Chemical paint stripping residue, including saturated rags, is hazardous waste. Please call 800-714-1195 for disposal.
  • Chips and dust from paints containing lead or tributyl tin are also hazardous wastes, and should be disposed of properly.
  • When stripping or cleaning building exteriors with high-pressure water, use sandbags or berms or seal the storm drain with plugs or rubber mats.

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Sediment from excavation and other construction projects is the most common pollutant washed from work sites. Sediment entering the ocean through storm drains harms fish and other wildlife.

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General Practices

  • Always store both dry and wet materials under cover, protected from rainfall and runoff and away from storm drains or waterways.
  • Keep all construction debris away from the street, gutter, and storm drain.
  • Look for and clean-up material that may have traveled away from your property after each day's work.
  • If you (or your contractor) keep a dumpster on your site, be sure it is securely covered with a lid or tarp when not in use.

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Erosion Control

  • Schedule grading and excavation projects for dry weather.
  • Cover excavated material and stockpiles of asphalt, sand, etc., with plastic tarps.
  • Prevent erosion by planting annual and perennial grasses. These will bind the soil, preventing erosion.

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Cover chemically-treated wood during rain events. This will prevent the chemicals from washing into storm drains.

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Hazardous Waste

Household toxins, such as common household cleaners, paint products, and motor oil can pollute the ocean and poison groundwater if not disposed of as hazardous waste.

Rather than dumping them in the sink or into a storm drain, take your toxics to Small Quantity Business Generator Hazardous Waste Disposal, by appointment only, 800-714-1195. Call 858-668-4702 for questions.

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A Word About "Biodegradable" Soaps

"Biodegradable" is a popular marketing term that can be misleading. Just because a product is labeled as biodegradable does not mean that it is non-toxic. Some products are more toxic than others, but none are harmless to aquatic life. Soapy water entering the storm drain system can have a negative impact on fish and other wildlife within hours.

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