Guest Blogger: preventing stormwater pollution during a remodel

Lastormwater_3Today's Guest Blogger is Veronica Britton on behalf of the city of Los Angeles Stormwater Program:

Did you know this: In Los Angeles County, about 100 million gallons of water and debris flow through the storm drain system each dry day. One hundred million gallons would fill the Rose Bowl 1.2 times! On rainy days, this daily flow can increase to 10 billion gallons.

So what does this have to do with you and your remodeling projects? Of course, completing DIY home projects certainly brings a sense of accomplishment and pride in your hard work. However, while you are working to improve the appearance and efficiency of your home, you may also be unintentionally contributing to environmental damage.

It is important to remember that when you undertake any home project, you can potentially allow toxic chemicals to flow into the storm drain system and eventually into the ocean (see photos). On a large scale, this pollution affects public health, closes beaches and harms aquatic life and their habitats.

The pollutants — including paint, motor oil, pesticides and fertilizers — are picked up as water from rainstorms, hoses and sprinklers drains from streets and lawns into 34,000 curb inlets, or catch basins, throughout the city of Los Angeles. From there, this "toxic soup" flows through a massive system of pipes and open channels straight to the beaches and ocean untreated.

It is the responsibility of every homeowner and avid DIYer to follow these best management practices in order to control and further prevent toxic substances from polluting communities, beaches and water bodies.

Click here to see tips for preventing stormwater pollution during: light construction, painting, paint removal and landcaping and gardening.

Light Construction

Fresh concrete and mortar application materials can wash down or blow into the street, gutter or storm drain, posing a hazard to sea life and humans. Here are some tips:

• Do not mix up more fresh concrete or cement than you will use.
• Store bags of cement and plaster under cover. Protect these materials from rainfall, runoff and wind, away from gutters and storm drains.
• Never dispose of cement washout or concrete dust onto driveways, streets, gutters or storm drains.


Paints and solvents contain chemicals that are harmful to sea life. Toxic chemicals can come from liquid or solid products or from cleaning residues on rags. Consider these tips:

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

Paint Removal

• Chemical paint stripping residue, including saturated rags, is a hazardous waste and should be taken to a household hazardous waste collection center.
• Chips and dust from marine paints or paints containing lead or tributyl tin are also hazardous wastes. Sweep them up and save them for proper disposal at a S.A.F.E. center.

The City of Los Angeles provides S.A.F.E Centers (Solvents, Automotive, Flammables and Electronics), collection facilities that accept residential hazardous waste. These six permanent locations are a free and easy way to properly dispose of unsafe materials. Call (888) CLEAN-LA or visit for addresses and business hours.

Landscaping and Gardening

Intensive gardening and landscaping increase the likelihood that garden chemicals and soil will wash into storm drains. Pesticides and herbicides not only kill garden invaders, they also harm insects, poison fish and contaminate ground and ocean water. Here are some tips:

• Use organic or non-toxic fertilizers and pesticides. Do not fertilize or use pesticides near ditches, gutters or storm drains.
• Store pesticides, fertilizers and chemicals in a covered area to prevent runoff.
• Do not blow, sweep, hose or rake leaves into the street, gutter or storm drain.
• Do not apply pesticides or fertilizers when you think it might rain soon.
• Conserve water by using drip irrigation, soaker hoses or micro-spray system; overwatering your lawn allows for excess water to travel through the street and carry debris and toxins into the catch basins.