Drain and Backwash Pools Legally & Safely
When you need to backwash your pool filter or drain the pool, try to use the water to
irrigate landscaping. Do not drain water into the street, alleyway or other right-of-way.
Take care when using pool water on landscaping since it contains more salt and chlorine
than tap water. Bermuda grass and Oleanders can be watered without much problem, but
avoid using this water on citrus, hibiscus, or other salt-sensitive plants. Also, avoid
spraying the water directly onto leaves or watering the same area repeatedly.
If you have to drain a large amount of water - such as emptying the whole pool - put it
down the home's sewer clean-out. The clean-out usually is located next to the house at
the point closest to the city sewer line and usually outside a bathroom or the kitchen. On
some older homes, the clean-out is located in the wall. On other homes, it is at ground
level, but may be hidden by landscaping. Older homes usually have only one opening,
while new ones have two clean-out pipes leading to the sewer line. A threaded cap,
usually black and 3 to 4 inches in diameter, covers the opening. If your neighborhood has
alleys, your clean-out probably is in your back yard. If there is no alley, it may be in the
front or side yard. If you cannot locate it, or a sidewalk or a patio has covered it, consult a
plumber about installing one.
Caution: Using a clean-out in the wall is risky and the potential for water backing up into
the home is great.
The maximum recommended discharge rate is 12 gallons per minute. The safe flow
rate may be less, depending on the size of the drain line, distance to the sewer main, and
the condition of the pipe. Most pool filter pumps will discharge too much water too fast
and may cause water to backup into the yard or the house. The safest approach is to rent a
submersible pump, connect it to a garden hose and slowly empty the pool. A pump that
operates at 700 gallons per hour is about the right size.
Note: Do not install the pool drain line as a permanent fixture. This may violate the city
plumbing code or county health regulations and could contaminate the water when you
refill the pool.
Procedure for using the sewer clean-out:
Locate the clean-out. If there are two, use the one closest to the home.
- Remove the cap and insert the drain hose a few inches into the pipe.
- Secure the drain hose so it won't pop out.
- Tum on the pump.
- Immediately check to make sure no water is backing up into the house. Drains for
showers and tubs are the first places to check.
- If the water backs up, turn off the pump immediately. You may have a blockage,
or the flow rate is too high.
- If you have a blockage, you will need to contact a drain cleaning service.
This chart shows how long the draining process will take, using the volumes noted.
HOURS REQUIRED TO DRAIN A POOL
Pool Volume (Gallons)
For questions regarding this process, please contact Neighborhood Services at
(623) 773-7099 or seek professional assistance from a qualified individual
specializing in pool drainage. Download a PDF copy of this information