Compost

Composting is an important component of "closed loop" recycling. We set regulatory standards for composting facilities, compost quality and provide technical assistance to local governments. By composting yard debris, food scraps, manure and crop residues, we can reduce the production of greenhouse gases and produce a valuable resource for farmers, orchardists, gardeners and muncipalities.

Washington has committed to reducing landfill-disposed organic material by 75% by 2030. By 2025, amount of edible food disposed of in the landfill must be reduced by 20%. Composting is a key tool to move organic waste out of the landfill.

See more benefits of composting in our publication “Why Compost?” (also en Español).

I want to...

List of Washington compost facilities.

See compost facilities that qualify for Washington State Department of Agriculture’s reimbursement program.

Composting is key to keeping organic waste out of the landfill

Composting at home

Several composting systems can help you manage food waste at your home, including outdoor yard bins, in-vessel systems and countertop grinding devices. Often, your municipal solid waste department will also offer tools for home composting. Be sure to contact them before purchasing any composting tools. They may have free or subsidized options.

At-home composting resources

For more technical training toward optimizing your compost:

Washington State University’s Master Composter Trainings

Vermicomposting is a great way to manage food waste at home. Vermicomposting is a process for converting food waste into a soil amendment by feeding food waste to red wiggler (eisenia fetida) worms. The worms live in a box or in a multi-level unit where they eat food scraps. This process results in “castings,” and in some cases, liquid “worm tea,” that act as soil enhancers when added directly to gardens, potted plants, or mixed into a soil-compost blend.

Depending on what materials you use and how much effort you put into it, you can develop hot compost, which composts quickly, or a cooler pile that can take months to compost. The more attention you pay to preparing the materials, generally, the better the compost.

A low touch, but slow backyard composting option is piling. Piling includes combining your yard waste in addition to some food scraps and letting the pile slowly decompose. While this doesn’t require significant management, it’s not guaranteed to create high-quality compost and may attract pests. Meat, oils, and dairy are not successfully managed with piling.

For more information, see Ecology’s Natural Yard Care Guide and Why Compost? (also en Español).

Some municipalities in Washington offer curbside collection for organic waste. For a fee, residents can contract to have organic waste regularly picked up.

If you are looking to identify your organic waste hauler in your area, start by asking your solid waste hauler.

Based on RCW 70A.205.540, beginning in Jan. 1, 2027, each jurisdiction that implements a local solid waste plan under RCW 70A.205.040 will be required to provide source-separated organic solid waste collection at least every other week or 26 weeks per year.

A map that outlines qualifying areas that are required to provide residential services will be available no later than Summer 2024.

If your municipality does not currently provide curbside service or you’re looking for an alternative, community composters can support you in managing your organic waste. Community composters are local composters that provide residential pickups or community drop sites for organic waste. They typically manage the waste to create compost that is used locally throughout the community.

You can use the Institute for Local Self-Reliance’s Composting for Community Map to find if one operates near you.

For more information, refer to your local government’s solid waste webpage or WSU Master Gardner resources. Or see the EPA's webpage on community composting.

Composting at my business

Many businesses produce organic waste from food services and production businesses, as well as from businesses that merely have food consumed at their workplace.

Similar to residential handling of organic waste, a business may contract for curbside pickup. If you are seeking to identify the organic waste hauler in your area, start by contacting your solid waste hauler.

If your business is located in a Business Organics Management Area (BOMA), it is presumed to have a viable organic waste hauler to provide curbside pickup service. BOMA maps will be updated each July.

Beginning Jan. 1, 2024, many businesses are required to arrange for organic material management. For more information, see our Organics management for businesses webpage.

Compost and agriculture

Composting often goes hand-in-hand with agricultural practices. Much of this compost activity is exempt from the Solid Waste Handling Permit process. See the agricultural exemptions within the composting regulations.

The primary agencies that provide assistance and oversight to agricultural operations are U.S. Department of Agriculture’s Natural Resources Conservation Service and Washington State Department of Agriculture.

Compost reimbursement for agriculture producers

Washington farmers are eligible for up to $20,000 in annual reimbursement costs for obtaining, transporting, and spreading compost produced by Washington compost facilities.

See WSDA’s map of compost facilities
See more WSDA information on reimbursement

Note to WA Compost Facilities: If you start or stop accepting food waste as a compost feedstock, or if you are not on WSDA's map and think you should be, please contact Michelle Andrews at: michelle.andrews@ecy.wa.gov or our Organics Team at organics@ecy.wa.gov.

Contact information

Organics management team
organics@ecy.wa.gov
509-960-1290