The vibrant colors of fall leaves are a beauty to behold every year in our region. The stunning display marks the end of summer and transition into winter. The leaves of fall provide more than just aesthetics, however. They also bring carbon, nitrogen, phosphorus, and potassium, along with other nutrients that can be used to feed gardens, and adding them to your compost pile is a great way to harness this nutrition. On the other hand, if leaves are left to make their way into local waterways, such as Coeur d’Alene Lake, this same nutrition can pose a threat to the health of our aquatic ecosystems.

Phosphorus and nitrogen are essential nutrients for growth. When leaves and pine needles shed in cool fall weather, they decompose and release nutrients. When it rains, fallen leaves may wash into lakes and rivers through storm drains and direct overland runoff. Excess nutrients that reach aquatic ecosystems can feed future algae and aquatic plant growth. Subsequent decomposition of this excess organic material consumes dissolved oxygen in the water column, posing a threat to organisms that depend on it for life. In Coeur d’Alene Lake, depletion of dissolved oxygen can also promote geochemical reactions that release mining-related heavy metal contaminates, such as lead, arsenic, zinc, and cadmium from lakebed sediments.

Nutrient inputs to waterbodies are a concern throughout the year but especially in autumn when leaves fall and wash into our lakes and rivers. A 2016 United States Geological Survey study in Madison, Wisconsin found that stormwater nutrient levels peak during fall months when large amounts of organic detritus (decaying organic material) littered streets. This nutrient load spike can be managed, however. The study found leaves contributed 56% of annual total phosphorus load in urban stormwater compared to 16% when streets were cleared of leaves prior to rain events.

Enter the City of Coeur d’Alene’s annual leaf pickup program, or “Leaf Fest,” as the city refers to it. This program not only provides a valuable service to city residents, it also protects water quality in Coeur d’Alene Lake and the Spokane River and provides organic matter and nutrients to land in need of it. City trucks pick up about 700 loads of leaves per year, equating to about 2,000 tons of leaves that would otherwise wash through the stormwater system into Coeur d’Alene Lake and the Spokane River, or would be bagged and sent to the landfill. The leaves are ground up into mulch, and then through a partnership with Kootenai County, they are hauled to the Coeur d’Alene Airport, where they are worked into ground that was stripped of its topsoil many years ago for use in yard remediation projects in the Bunker Hill Superfund Site in the Silver Valley.

Join Leaf Fest 2023!

Residents are encouraged to rake their leaves and needles into the street for the city to remove, making sure to leave space (1 foot at a minimum) between the leaf piles and the curb for stormwater to drain freely and prevent those nutrients from reaching the storm drains. This year the City will begin picking up leaves that are piled in the streets Nov. 13 at 7 a.m. They will begin south of Sherman Ave and move north.

Unfortunately, weather doesn’t always cooperate. You may recall last year’s strange fall. It was wet, and then temperatures dropped quickly. Some leaves didn’t even get a chance to fall off the trees! Many piles of leaves actually froze to the ground. Todd Feusier, Director of the City of Coeur d’Alene’s Street and Engineering Department explained, “That was all Mother Nature. The weather was just not conducive for leaf pick up last year.” He’s hoping this year will run smoothly.

Here are some tips for Coeur d’Alene residents to participate:

• Move vehicles, trailers, basketball hoops, etc. off the street.

• Keep leaves one foot from the curb to allow for stormwater flow.

• Keep leaves away from storm drains.

• Do not mix branches, debris or other trash in with the leaves.

• Stay clear of machinery picking up the leaves (they move quickly).

• There is only enough time for one pass through each neighborhood, so rake your leaves into the street now. 

The Our Gem Coeur d’Alene Lake Collaborative is a team of committed and passionate professionals working to preserve lake health and protect water quality by promoting community awareness of local water resources through education, outreach and stewardship. Our Gem includes local experts from the University of Idaho Community Water Resource Center, Coeur d’Alene Tribe, Idaho Department of Environmental Quality, the Basin Environmental Improvement Project Commission, Kootenai Environmental Alliance, Coeur d’Alene Regional Chamber of Commerce and Connect Kootenai.