GRAND RAPIDS, Mich. (WOOD) — Whether you like it or not, summer is about over in West Michigan. Soon, the temperatures will dip lower, the leaves will turn color and the Halloween decorations will take over.

For pool owners, that means it’s time to winterize, and the state Department of Environment, Great Lakes and Energy wants people to know that there’s an environmentally friendly way to drain your swimming pool.

According to Chris Veldkamp, an environmental quality specialist with EGLE’s Water Resources Division, the primary concern is chlorine.

“Chlorine, while it’s something that we drink every day in our portable water, can be toxic at certain concentrations in rivers, creeks and streams,; actually very, very low concentrations,” Veldkamp told News 8.

The most effective thing pool owners can do is to let the pool sit for at least two weeks without adding any chlorine before starting the draining process.

“We ask homeowners to let the pool sit,” Veldkamp said. “Chlorine will dissipate with wind, with sun, just basically open exposure to air, and it will lower those concentrations on their own just in that short period of time.”

While it is a lesser concern in communities with municipal water systems — which treats wastewater before it gets recycled back into the city supply — it can be dangerous for people who rely on well water and the surrounding environment.

“If it goes into our waterways, it’s toxic to the aquatic environment,” Veldkamp said. “Fish could very well be killed. Important insects and whatnot that live in the water can also die from it, again, even at very low concentrations.”

For people on municipal waters, EGLE also asks people to make sure they aren’t carrying more debris into storm sewers during the draining process.

“No leaves, no dirt. There should be no filter backwash that’s included in there. All we want is just plain pool water,” Veldkamp said. “And if you’re going to discharge it through a hose, try to do it in a way that doesn’t pick up anything as it goes down the driveway or goes down into the gutter or wherever else it goes. Be conscientious about what’s there. Maybe you want to sweep up that area.”

She continued: “If you’re going to (drain pool water) on your land … you have to be conscientious about how fast you discharge it. It should soak into the ground. We don’t want it to erode property and we certainly don’t want to impact neighboring properties.”