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Does Flushing Your Toilet Protect Our Lake?

If you live in the City of Coeur d’Alene, you bet it does! In ways that might not be immediately obvious. Wastewater from your house, that is the water that goes down your drain from your shower, your washing machine, your dishwasher, your sinks, and yes, your toilets, eventually ends up at the Coeur d’Alene Advanced Wastewater Treatment Facility. It is here where all the solids are removed from the wastewater.

But what happens to those solids? I remember learning in my Environmental Science class that when you throw something away, really “there is no away”. That truism applies here as well and the solids must go somewhere. At the treatment facility, the solids undergo a series of thickening and anaerobic digestion processes where microscopic bacteria almost magically transform them from a literal waste into a “Class B” biosolid. Almost every day of the year, approximately 20 yards of these biosolids are hauled from the Treatment Facility to the City’s Coeur d’Green Compost Facility where the product spends an additional 60 days composting before it is available as a “Class A, Exceptional Quality” product made available to the public through various neighborhood resellers.

While this sounds like a great story, the true magic is the second half of the story and what Coeur d’Green Compost does for our soil and in turn, Our Gem, Lake Coeur d’Alene. Coeur d’Green and all biosolids are full of both organic matter and nutrients. Beyond the standard nitrogen, phosphorous and potassium you might find in fertilizers it also contains micro-nutrients and “good” microbes. Exactly what poor soils often found in our area need. Lastly and just as important, Coeur d’Green like all composts, improve the physical characteristics of the soil. Dense and heavy clay soils are broken up with the addition of compost making them drain more effectively while sandy soils benefit from the organic matter and are better able to retain water.

Let’s take a quick dive into what Coeur d’Green Compost is and what it isn’t. It reacts very differently than chemical fertilizers. While it does have nitrogen, phosphorous and potassium they are in much lower quantities than the bag of 16, 16, 16 found at your local big box store. Compost is more like 3, 3, 0.3 but it offers these nutrients at a slow release rate so that the nutrients are available to the plant for longer rather than leaching into the ground. Compost is also providing the micro nutrients and biology to keep your soil “alive”. A healthy plant starts with a healthy root and compost helps to develop root growth by improve soil porosity and providing the micro-nutrients and microbes that chemical fertilizers likely won’t have. These more robust root structures not only make for healthier plants but improve soil retention, protecting our waterways from runoff and its associated consequences.

So yes, flushing your toilet in Coeur d’Alene really does make a difference. To learn more, you can visit

University of Idaho

Physical Address:
1031 N. Academic Way,
Suite 242
Coeur d'Alene, ID 83814

Phone: 208-667-2588

Fax: 208-664-1272



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