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      Department of Public Works Bureau of Sanitation

Did you know that horse waste can pollute our waterways?

The fact is, even though manure is natural and organic—when it washes into streams or to the ocean through the storm drain system, its harmful bacteria can cause problems for swimmers, and its fertilizing action can harm sea life by decreasing the oxygen levels in the water.

There are 1,500 horses licensed to City of Los Angeles residents and collectively, they generate over 9.4 tons of manure daily in the City.

Animal waste contributes to ocean pollution when it is improperly stored or left uncovered near small streams and storm drains. During rainfall, it is washed into storm drains and flows untreated, directly into the ocean. Equine facilities generate manure and horse waste that runoff into the soil (left) or into storm drain channels (below).

Sediment is also a common pollutant washed from pastures and livestock facilities. It creates multiple problems once it enters the ocean. It harms sea life by clogging the gills of fish, blocking light transmission and increasing ocean water temperature.

Facilities Design

  • Site barns, corrals and other high-use areas on the portion of property that drains away from the nearest creek or stream.
  • Install gutters that will divert runoff away from livestock area.
  • Design diversion terraces which drain into areas with sufficient vegetation to filter the flow.
  • Protect manure storage facilities from rainfall and surface runoff.

Pasture Management

  • Confine animals in properly fenced areas except for exercise and grazing time.
  • Corrals, stables and barns should be located on higher ground when possible and surrounded by pasture to act as a natural filtration system.
  • Utilize fencing to keep horses away from environmentally sensitive areas and protect stream banks from contamination.
  • Use manure and soiled bedding sparingly to fertilize pastures and croplands.

Grazing Management

  • Establish healthy and vigorous pastures with at least 3 inches of leafy material present.
  • Subdivide grazing areas into three or more units of equal size.
  • Clip tall weeds and old grass to control weeds and stimulate grass regrowth.
  • Rotate animals to clean pasture when grass is grazed down to 3-4 inches.
  • Let pasture regrow to 8-10 inches before allowing regrazing.
  • Keep animals away from wet fields when possible.
  • During heavy rainfall, consider indoor feeding, a practice which keeps more manure under roof and away from runoff.

Collection and Storage

Collect soiled bedding and manure on a daily basis from stalls and paddocks and place in temporary or long-term storage units. Store in sturdy, insect resistant and seepage free units such as:

  • Plastic garbage cans with lids.
  • Fly-tight wooden or concrete storage sheds.
  • Composters.
  • Pits or trenches lined with an impermeable layer.

Use and Disposal

  • Compost soiled bedding and manure for your own use.
  • Give away composted material to local greenhouses, nurseries and botanical parks.
  • Transport manure to topsoil companies or composting centers.
  • Fertilize pastures, cropland and lawns with manure and soiled bedding. Do not apply fertilizer just before or during rainstorms.

Collect soiled bedding and manure daily and store in sturdy units such as a garbage can.

Protect manure storage facilities from rainfall.

Pesticides Alternatives

The "chemicals only" approach to pest control is only a temporary fix. Integrated Pest Management is a more common sense approach for a long-term solution. Plan your "IPM" strategy in this order:

Physical Controls

  • Pheromone Traps
  • Tarps
  • Bug Zappers
  • Fly-Tight Storage Sheds

Biological Controls—"Nature’s Way"

Encourage the use of swallows, bats and other insect eating animals on your residence over the use of pesticides.
For more information, call: 1 (800) 974-9794

Chemical Controls – Your Last Resort

Use these least-toxic products:

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

Horse manure is a valuable resource and can be composted. Donate composted material to local green-houses, nurseries and botanical parks.


Transport manure to topsoil
companies or composting centers.

Fertilize pastures, cropland and lawns with manure and soiled bedding.

Call (800) 773-CITY or click here to arrange horse manure pickup from the City of Los Angeles. A nominal collection fee is charged monthly for a 30-gallon container.

You can also download the following guides,
Water Pollution Solutions For Horse Owners

Best Management Practices for the Equine Industry