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      Department of Public Works Bureau of Sanitation

The City of Los Angeles wants you to know …

Discharges of water to the street gutter flow untreated through storm drains to our arroyos, creeks, river; and ultimately, the ocean. Any pollutants present in the water are not removed prior to reaching the ocean.
It is therefore very important that the water contain no pollutants.

The City of Los Angeles allows the periodic draining of swimming pools, spas, and decorative fountains to the street gutter, storm drain, or sanitary sewer, provided that certain Best Management Practices are followed.

Proper Disposal of Water from Swimming Pools, Spas, & Fountains

  1. Water from swimming pools, spas, or decorative fountains must be dechlorinated or debrominated prior to discharge to the street, storm drain, or sanitary sewer. Suggested methods are:
    • Allow the pool water to sit in the pool without adding chlorine. Chlorine levels will drop naturally over several days.
    • Add a dechlorinizing agent to the pool water. A common chemical used for this purpose is sodium thiosulphate. Different products are available in the market to accomplish this action.
    • Using a pool test kit, check the residual chlorine level prior to discharging. Discharge water when residual chlorine measures zero.
  2. The dechlorinated or debrominated pool water may be drained to the storm drain or sanitary sewer. If draining to the sanitary sewer, a P-trap (3 -inch minimum) shall be required with adequate trap seal protection as per section 310.3 of the Uniform Swimming Pool, Spa and Hot Tube Code [L.A.M.C. Section 94.1007.0]. No trap or vent is required for connections to the storm drain system.
  3. In order to prevent hydraulic overload of the sanitary sewer, pool water may not be discharged to the sanitary sewer within one to two days after the cessation of a rain event.
  4. Pool, spa or fountain water containing copper-based algaecides may not be discharged to the storm drain or sanitary sewer.
  5. Fountain water containing a dye may not be discharged to the storm drain. Discharges of dyed water to the sanitary sewer are conditional pursuant to L.A.M.C. 64.30.
  6. Maintenance discharges from swimming pools, fountains and spas such as filter backwash, acid wash, and plaster wastes shall never be discharged to the public right-of-way or storm drain system.
  7. Do not drain swimming pool, spa or fountain water in such a manner that the water encroaches on an abutting property or floods the public right-of-way.
  8. Do not drain, or cause to be drained, pool, spa or fountain water into any private sewage disposal system (e.g. septic tanks, cesspools, etc.).
  9. When discharging to a storm drain, exam the catch basin. If the catch basin contains trash, debris, oil, chemicals, and other waste, notify the Wastewater Collections Division of the Bureau of Sanitation regarding the planned discharge, in order to ensure the affected storm drain catch basin is clean of any debris or trash.
    Clogged catch basins may cause the discharged water to flood surface streets. The Wastewater Collections Division phone numbers are as follows:
    i. Valley/West Los Angeles areas: 1-818-345-2107
    ii. All other areas: 1-213-485-5392

    The notification should be at least 72 hours in advance of the planned discharge.

  10. Ensure your service personnel and others drain the pool, spa, or fountain according to the mandated Best Management Practices.
  11. Discharges to the storm drain shall be between the hours of 8 pm to 8 am.

Pool Deck and Area Drains

These drains should not be connected to the sanitary sewer, but may be connected to a dry well or the storm drain system.

Backwash of Pool Filters

Pool filter back wash may not he drained to the storm drain system or public right-of-way. Pool filter back wash may be drained to the sanitary sewer provided:

  1. the water passes through a separation tank prior to discharge;
  2. the connection is in compliance with all applicable plumbing regulations,
  3. Provided there are no harmful chemicals present, the diatomaceous earth filter waste may be dried and deposited in the trash or used in the garden as a soil amendment.
Other BMPs

Automotive Industry & Repair

Heavy Equipment Operators

Horse Owners & Equine Industry

Home Repair & Remodeling

Land or Air Transportation Facility

Landscape, Gardening & Pest Control

Manufacturing Facilities


Restaurant Industry

Sewage Systems

Water-based Cleaners

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