Your trash deserves better. These three cases show what’s possible.

How an ‘All-In’ approach can slash planet-warming methane emissions from the waste sector

Landfills are the third largest source of methane in the United States with annual emissions equivalent to driving 66 million cars or operating 79 coal-fired power plants. Methane is generated when organic materials — such as food waste, yard waste, and paper — decompose in landfills without oxygen. In the United States, we send more than 145 million tons of waste to municipal landfills each year. Food waste is the single most landfilled material, causing nearly 60 percent of landfill methane emissions, according to recent EPA analysis.

Cutting methane is the strongest lever we have to slow the rate of near-term warming and limit the risk of dangerous climate tipping points. In the waste sector, strategies to cut methane emissions fall into two broad categories: upstream prevention and downstream mitigation.

Upstream strategies center around the Environmental Protection Agency’s (EPA) Wasted Food Scale and prioritize waste prevention, food donation, and recycling to turn residual organics into animal feed, compost, or biogas. Downstream strategies focus on improving landfill design, operations, and monitoring practices to increase methane capture and reduce methane leaks. Upstream strategies avoid locking in future landfill methane emissions and ensure organic materials are put to their highest and best use, while downstream strategies are critical to cut methane quickly from all the organic waste already sitting in our landfills today.

The Center for Global Sustainability (CGS) at the University of Maryland estimates an “All-In” approach that combines upstream and downstream efforts could slash waste methane emissions by 15 percent by 2030. These emission reductions would help the United States deliver on the North American Leaders’ Summit commitments, the Global Methane Pledge, and its broader nationally determined contribution (NDCs).

Beyond the climate benefits, cutting methane emissions from the waste sector can help to address food insecurity, reduce health risks, improve quality of life for landfill-adjacent communities, create circular economy jobs, and produce value-added products, like compost.

Three success stories in waste methane mitigation

State of Maryland

Landfills are the largest source of methane emissions in Maryland, making up about 40 percent of the state’s methane emissions and about 6 percent of total greenhouse gas emissions.

Maryland methane emissions
Exhibit 1: Maryland’s greenhouse gas emissions in 2020.
Source: COMAR 26.11.42 –Control of Methane Emissions from Municipal Solid Waste (MSW) Landfills

Maryland has successfully implemented upstream and downstream waste management policies to address these harmful emissions. Maryland’s organics recycling law requires businesses, organizations, and schools that generate at least two tons of food residuals per week (one ton per week beginning in 2024) and are located within 30 miles of an organics recycling facility, to separate and divert food residuals from landfills or incinerators. Acceptable alternatives include source reduction, donation, conversion to animal feed, composting, or anaerobic digestion. Maryland is now home to one of the largest municipal composting facilities on the East Coast (Prince George’s County), and the Baltimore Compost Collective in South Baltimore is working to recycle food waste, improve soil health, and develop youth leaders in a community that was once slated to host the country’s largest toxic trash-burning incinerator.

Downstream, Maryland recently finalized a new rule to guard against methane pollution. The rule makes several improvements to landfill design and operations that will meaningfully increase methane capture and reduce the risk of large leaks. When fully implemented, the Maryland rule will reduce greenhouse gas emissions from landfills by an estimated 25-50 percent. Maryland is now the third state after California and Oregon to set stronger landfill standards than the EPA’s.

UMD’s CGS estimates that these policies can deliver 39 percent gross emission reductions in Maryland’s Climate Pathways scenario by 2031, or roughly 4 percent of the state’s 60 percent reduction target, while delivering co-benefits to Marylanders through improved environmental health.

City of Austin, Texas

Austin is a national leader in sustainable resource recovery with an ambitious goal to reduce the amount of trash sent to landfills by 90 percent by 2040. The city has made significant progress on its zero-waste goals, achieving a 42 percent diversion rate in 2021.

Austin Resource Recovery (ARR), the city’s solid waste utility, has implemented several programs over the past decade to reduce organic waste disposal in landfills and promote sustainable materials management throughout the city. ARR provides weekly curbside composting collection to more than 220,000 residential customers, converting food scraps, yard trimmings, food-soiled paper, and natural fibers into nutrient-rich compost. Austin offers free composting guides and zero-waste classes for K-12 students to expand uptake and awareness.

Private haulers manage the waste streams of commercial and multi-family properties, but the city of Austin has enacted policies and programs to increase organics diversion among these generators. For example, Austin passed a universal recycling ordinance (URO) that requires food-permitted businesses to ensure convenient access to diversion methods that keep organic materials out of landfills, encouraging waste prevention, edible food recovery, and composting. Austin City Council recently approved an amendment to the URO that will expand composting services to multi-family properties.

Austin also provides incentives and resources to advance organic waste reduction, donation, and recycling efforts. The city offers a Zero Waste Business Rebate to encourage and support food rescue infrastructure, with up to $3,000 available to businesses for expenses related to improving food storage or equipment for the transport of recovered food. In 2015, the city launched the ReVerse Pitch Program an annual competition with a $10,000 prize and small business support for start-up circular businesses that aim to turn waste into new products.

ARR’s Assistant Director, Gena McKinley, cited several benefits to the city’s waste management strategy, beyond emissions reductions. For one, the curbside composting program is beneficial to ratepayers, as the cost to compost organic materials is lower than the cost to landfill them, and the city passes along these savings to residents. Second, the incentives and programs focused on increasing edible food recovery can help to address food insecurity, which impacts about 15 percent of residents (see the Austin Climate Equity Plan and Austin’s State of Food Systems Report). Finally, circular economy programs can create new workforce training and job opportunities, and ARR has partnered with the city’s economic development department to help grow the local circular economy.

Sierra Nevada Brewing Company

Sierra Nevada Brewing kettle

Sierra Nevada Brewing Company is the third largest craft brewery in America and the first TRUE Platinum Zero Waste certified business with an over 99 percent diversion rate of solid waste from the landfill.

Spent grain and spent yeast are the largest volume of waste generated by breweries. Sierra Nevada generates about 250,000 pounds per day of spent grain across its operations. Through farm partnerships, the spent grain is then used as cattle feed for dairy cows and is a revenue stream for the company. The company sends part of its spent yeast (~40,000 lbs/day at its California facility) to farms as animal feed for dairy cows, and the remainder (~30,000 lbs/day at its North Carolina facility) is anaerobically digested at an on-site wastewater treatment plant along with the brewing effluent. The biogas produced at Sierra Nevada’s North Carolina digester is used in boilers and microturbines, covering about 8 percent of total electricity needs.

At its California restaurant and taproom, Sierra Nevada has installed an industrial on-site composter to process food waste, landscaping debris, and small amounts of hops and spent grain. The in-vessel composter can process over 2 tons of organic material per day, and Sierra Nevada estimates it has prevented over 6 million pounds of organic material from reaching landfills, which in turn has avoided almost 2,000 metric tons of CO2e over its lifetime. Sierra Nevada utilizes much of the compost for agricultural purposes on-site, growing produce, herbs, hops, and barley. At the North Carolina taproom, Sierra Nevada diverts food waste to a regional composting facility.

Sierra Nevada also prevents waste at its California location by donating edible food from its taproom and estate garden to shelters, food banks, and youth organizations. To help facilitate the donations, the brewery has partnered with 530 Food Rescue, a non-profit organization that connects food-rescue volunteers to retailers using a mobile app.

Opportunities to Scale Impact

These three case studies illustrate some of the many policies and programs that can reduce methane emissions while delivering powerful co-benefits.

Historic funding from the Bipartisan Infrastructure Law (BIL) and the Inflation Reduction Act (IRA) can help support and scale subnational efforts to cut waste methane. For example, the Solid Waste Infrastructure for Recycling (SWIFR) Grant Program from the BIL recently invested more than $100 million in local waste infrastructure, including support for organics collection and composting facilities.   The IRA’s Climate Pollution Reduction Grant Program (CPRG) provides $5 billion in climate planning and implementation grants to states, local governments, tribes, and territories to develop strong, local greenhouse gas reduction strategies. Applicants must submit a priority climate action plan (PCAP) by March-April 2024 to compete for implementation funding, and we encourage entities to include food waste reduction, organics diversion, and landfill mitigation programs in their PCAPs.

The EPA can also help scale efforts to reduce landfill emissions by strengthening the Clean Air Act regulations for landfills to slash planet-warming methane, protect landfill-adjacent communities across the country, and make progress on broader climate and environmental justice goals. The 2023 United Nations Climate Change Conference (COP28) at the end of this year is an exciting opportunity for the United States to highlight subnational progress and announce action to further cut landfill methane.

RMI’s Waste Methane Resource List compiles additional funding opportunities, sector-specific toolkits, and model programs and policies to help states, local governments, and organizations take action to reduce food waste and landfill methane emissions. Our trash is a major contributor to climate change, but with an ‘All-In’ approach, we can change that.

This article highlights success stories discussed in Tackling Food Waste & Landfill Methane Emissions an event hosted by the America Is All In Coalition and RMI to explain the link between trash and climate change and present solutions for subnational actors.

America is All In is an expansive coalition of over 5,000 state, tribal, and local governments, higher ed institutions, businesses, health care organizations, faith groups, and cultural institutions in support of US climate action at the federal and subnational level.