Handling Water from Swimming Pools and Hot Tubs

Water from swimming pools and hot tubs often contain high levels of chlorine. Discharging chlorinated pool or hot tub water into streams (or drainage ways, ponds, etc.) is harmful to fish and other aquatic life. Hamilton County Public Health developed this fact sheet to provide you with management practices that will minimize the impact of chlorinated water discharged from swimming pools and hot tubs. The following ‘Best Handling Practices’ apply to water discharged from swimming pools, hot tubs or other chlorinated waters.


Pools and hot tubs have two types of water

Backwash water is the waste product produced by cleaning a filter through a method of reversing the flow of water inside the filtration system.

Pool/hot tub water is the water in your pool or hot tub that is normally treated with chlorine.


What do I do with backwash water?

Filter backwash water contains pollutants and must be discharged to the sanitary sewer, not a storm drain. Sanitary sewers are specifically designed to transport wastewater to an appropriate treatment facility. In unsewered regions, backwash water must be discharged to a subsurface absorption trench. Backwash water can never be discharged into a storm sewer system or septic system.


Can pool/hot tub water be directed to a storm drain or sanitary sewer?

Do not discharge chlorinated water from your pool or hot tub into a storm drain. Discharging chlorinated water into the sanitary sewer is also generally not an option in Hamilton County, Ohio. If necessary, the Metropolitan Sewer District (513-352-4900) or applicable local sewer utility can be contacted for special permitting.


Can pool water be released on the owner’s land?

Chlorinated water from pools and hot tubs may be disposed of on the ground or irrigated on your property under the following circumstances:

  • Prior to disposing or irrigating the water, either shut off the chlorination system or stop adding chlorine, depending on your situation.
  • Hold the water in the pool or hot tub for at least two days to allow the chlorine to dissipate. Up to two full weeks may be necessary for the complete dissipation of the chlorine.
  • The pH (measure of acidity) of the dechlorinated water must be at least 6.5, but not greater than 8.5. The pH must be measured with a standard swimming pool water pH test kit.
  • Discharge or irrigate the water in an area where the water will not flow into a stream, drainageway or storm sewer.
  • Discharge or irrigate the water on your property and ensure that it does not flow off of your property
  • Discharge or irrigate the water in a manner that will prevent nuisance conditions (such as creation of odors, and fly and mosquito breeding conditions). Nuisance conditions often occur when water is ponded for a prolonged period.
  • If draining the water cannot be contained onsite, contact the Water Quality Division at (513) 946-7966 for other potential options.



For more information, or if you would like to report an improper pool and/or hot tub discharge, contact the Water Quality Division at (513) 946-7966.

To ensure all storm water rules and regulation are being followed, click on the following link: (see Article III and Article V)


Download a printable version of this fact sheet here.


250 William Howard Taft Road
2nd Floor, Cincinnati, OH 45219
Phone 513.946.7800 Fax 513.946.7890