Safe Environmental Habits and Procedures for Gardeners, Homeowners and Landscapers

The City of Torrance has two drainage systems – the sewers and the storm drains. The storm drain system was designed to prevent flooding by carrying excess rainwater away from city streets out to the ocean.

During storms in urban areas, rainwater may mix with pollutants in industrial and household runoff, creating storm water pollution.

Most runoff from the streets of Torrance discharges directly to the Pacific Ocean via the storm drain system. Activities from landscaping, gardening and pest control can be major sources of storm water pollution, including pollutants that are of primary concur. These include trash from improper waste disposal, nutrients and bacteria from food wastes and landscape maintenance, and oil from vehicle fluids leaked on parking lots.

Look for curbside catch basins and other storm drain inlets in and near the workplace. These should be labeled with stencils that say “NO DUMPING: DRAINS TO OCEAN.” All of us need to make sure that only clean storm drain water runoff is allowed to enter these inlets.

PROBLEMS: Landscaping and garden maintenance activities can be major contributors to ocean pollution. Soils, yard wastes, overwatering and garden chemicals become part of the urban runoff mix that winds its way through streets, gutters and storm drains before entering the ocean.

Poorly functioning sprinklers and overwatering, for example, waste water and increase the number of pollutants flowing into storm drains.

Fertilizers, pesticides and herbicides are washed off lawns and landscaped areas. These chemicals not only kill garden invaders. They also harm useful insects, poison fish and contaminate ground and ocean water.

Leaves, grass clippings and tree trimmings that are swept or blown into the street and gutter are also ocean polluters. These wastes clog catch basins, increasing the risk of flooding on your street, and carry garden chemicals into the ocean. As they decompose, they also absorb oxygen fish need to survive.

SOLUTIONS: Best Management Practices that include the proper handling, storage and disposal of materials can prevent pollutants from entering the ocean through the storm drain system.


  • Protect stockpiles and materials from wind and rain by string them under traps and secured plastic sheeting.
  • Schedule grading and excavation projects for dry weather.
  • Sweep up dry spills immediately and dispose of the materials in the trash.
  • Prevent erosion by planting fast-growing annual and perennial grasses. These will shield and bind the soil.


  • Do not overeater. Conserve water by using irrigation practices such as drip irrigation, soaker hoses and micro-spray systems.
  • Place all landscaping waste in approved green waste containers for pickup and composting.
  • Do not blow or rake leaves into the street, gutter, parkways, or storm drains.
  • Use organic or non-toxic fertilizers.
  • Do not over fertilize and do not fertilize near storm drain inlets or near paved areas that may carry runoff to storm drain inlets.
  • Store pesticides, fertilizers and other chemicals in a covered area to prevent runoff.


The “chemicals-only” approach to pest control is only a temporary fix.

A more common-sense approach is needed for a long-term solution. It is called Integrated Pest Management (IPM).

Plan your IPM strategy in this order:

A) Physical Controls

  • Caulking holes
  • Traps
  • Barriers
  • Hand picking

B) Insect Controls
  • Predatory insects (e.g. green lacewings eat aphids)
  • Bacterial insecticides (e.g. bacillus thuringiensis kills caterpillars)

C) Chemical Controls – Your Last Resort

Use these least-toxic products:

  • Dehydrating dusts (e.g. silica gel)
  • Insecticidal soaps
  • Boric acid powder
  • Pyrethrin-based insecticides
  • Horticultural oils


Garden Aphids & Mites – Mix 1 tablespoon of liquid soap and 1 cup vegetable oil. Add 1 teaspoon of this mixture to a cup of water and spray.

Caterpillars – Products containing Bacillus thuringiensis.

Ants – Boric acid powder or hydramethynon baits.

Roaches – Boric acid powder

  • Use a pesticide that is specifically designed to control your pest. The insect should be listed on the label. Approximately 90% of the insects on your lawn and garden are not harmful.
  • Read Labels! Use only as directed. In their zeal to control the problem, many gardeners use pesticides at over 20 times the rate that farmers do.


  • Household toxics – such as pesticides, cleansers, and motor oil, can pollute the ocean and poison groundwater if disposed of in storm drains or gutters.
  • Rinse empty pesticide containers and use rise water as you would the product. Empty rinsed containers may be recycled depending on their type or may be thrown in the trash.
  • City of Torrance residents can dispose of unused household toxics at Hazardous Waste Round Ups.

Call 1-888-CleanLA or log onto for more information.
Dumping toxics into the street, gutter or storm drain is illegal!