Safely Discharging Pool Water

Labor Day weekend is the time many homeowners choose to winterize their swimming pools. In doing so, many will drain their pools completely while others will drain to just below the inlets for the pump. Whatever the situation, pool owners are advised to follow a few practical guidelines to insure that the water being discharged will not cause problems to the environment. Guidelines are as follows:

  • Contact you local sanitary sewer operators before discharging pool water to the sanitary sewer system.
  • Do not discharge chlorinated water directly to a storm drain or to a water body.
  • To discharge directly into the environment, discharge over the land surface following water quality criteria.
  • Dechlorinate water before discharging.  Water should sit for at least 2 days after the addition of chlorine or bromine until levels are below 0.1 mg/l.
  • The pH of the water should be between 6.5 and 8.5 before it is discharged.
  • Allow suspended particles to settle out of the water before discharging. Suspended solids should be below 60 mg/l.
  • If suspended particles are present, discharge should be directed over land surface so that some level of filtration by soil particles can occur.\
  • Residential pools should discharge backwash water to the sanitary sewer.
  • Algaecides such as copper or silver can interrupt normal algal and plant growth and should not be used.
  • When discharging over the land surface, remember you neighbors and don’t discharge at a rate causing erosion.

Why is it so important to keep chlorinated water out of local water bodies?  Chlorinated water discharged to surface waters has an adverse impact on local water quality.  Swimming pools are a major source of chlorinated water discharged into sanitary and storm drain systems.  An average swimming pool holds 19,000 gallons of chlorinated water.  Pools have high concentrations of chlorine, which is toxic to wildlife and fish.  Handling pool water responsibly can insure a healthier environment.

Information provided by US Environmental Protection Agency fact sheet and Southeast District Office of the Ohio Environmental Protection Agency.