Draining your pool without killing your lake

I don’t want to alarm anyone by talking about the end of summer, but I recently took a good hard look at the calendar and realized the end is near. A friend of mine recently posted a photo on Facebook of Halloween candy already on display at her local convenience store. I was shocked, because I assumed that they would have moved on to candy canes by now. Yes, it is still August, but if I were you, I would avoid taking any long naps in case you accidentally miss the last few days of flip flops, convertibles and swimsuits.

Chlorine is good for pools, not lakes. Pictured – Charlie Hong and his mom

Growing up in California, everyone had a swimming pool (except for us, of course.) Here, they are much less common, although many people do have hot tubs (except for us, of course.) If you are one of the lucky people who own a pool or hot tub, enjoy it now before the reindeer start flying. Also, be sure to use a little caution when you drain your water for the year to ensure that chlorine and other pool chemicals don’t end up in a nearby wetland, lake or stream.

The easiest and most common way to drain a pool or hot tub is to let the water drain out into the yard or the street. However, streets connect to wetlands, streams and lakes through underground storm sewer pipes and above ground ditches.  Water from swimming pools and hot tubs often contains high levels of chlorine, bromine, and copper. It is also very corrosive due to low pH levels and may contain organic matter. If you discharge untreated pool water into your yard or the street, you can damage vegetation and kill fish and aquatic life. For this reason, it is illegal to discharge chlorinated water to a municipal storm sewer system. Don’t end up in the police blotter in your local paper. Don’t dump chlorinated water into the street or your local lake!

Happily, there is an easy solution. Before draining your pool or hot tub for the season, stop adding chlorine and leave the water exposed to the air for three to five days until it becomes naturally de-chlorinated. You can also use de-chlorinating chemicals from a pool or spa supplier to remove the chlorine more quickly. Before dumping the water, use a test kit to ensure that it has been de-chlorinated to less than 0.1 mg/L of chlorine, has a pH range of 7-8, consists only of water, and is discharged in a way that does not cause nuisance conditions or erosion problems. Direct the water onto a vegetated surface so that as much water as possible soaks into the ground and don’t flood your neighbor’s yard.

If your house is connected to a municipal sewer system and you can easily discharge your pool water into a utility sink or floor drain inside the house, then that is an option as well. Chlorine, in small amounts, is typically not a problem for municipal water plants, but don’t do this if you have a septic system. Wastes from pool filters and back wash systems are not allowed in the storm sewer system and should be directed to an indoor drain, while pool filters can be disposed of with your regular garbage.

As summer wanes to fall, it is important to remember that I do not and have not ever owned a pool or spa. If you do, invite me over to enjoy the good life soon before the weather turns. Then, be sure to treat and dispose of your water properly to avoid poisoning local wetlands, lakes and streams.