The moderator’s question was simple: If local programs want to move beyond weight-based recycling rates, what single metric should be used instead?

“I have prepared my answer for this,” said city of Seattle economist Jenny Bagby before emphatically holding up a sheet of paper and taking a pause. “I don’t know.”

The exchange drew laughs from the room full of Pacific Northwest recycling leaders who were gathered earlier this month in Seattle for a recycling metrics event called the SPU Measurement Symposium.

But beneath the chuckling was a solemn fact: The recycling industry is lacking a definitive answer on how to track progress as it aims to better align itself with society’s larger environmental, equity and resource-use objectives.

The full-day Seattle discussion, which was organized by Seattle Public Utilities (SPU) and Cascadia Consulting Group, laid bare the complicated nature of moving away from current measurement strategies that sit at the heart of most municipal programs. It also shed light on some ideas that could reshape how we frame materials diversion success going forward.

Recently, major waste diversion stakeholders including the U.S. EPA, hauling giant Waste Management and the state of Oregon have strongly urged municipalities, residents and others to start thinking in terms of sustainable materials management (SMM), a concept in which complete material life cycles are taken into account when designing programs and policy.

One key element in the wider SMM discussion has been de-emphasizing the practice of assessing programs solely through weight-based recycling rate calculations.

Recycling rates in their simplest form show the weight of recovered material as a percentage of the total weight of waste generated in a given community or program. Such calculations have long been disparaged by some in the industry because different jurisdictions include different materials and disposition methods in their calculations. This all leads to rate comparisons that many deem to be unfair.

But as more industry leaders try to assess how programs can help on issues such as climate change and environmental justice, recycling rates are encountering a new level of criticism.

“Recycling primarily helps the environment because it conserves resources and reduces pollution,” David Allaway of the Oregon Department of Environmental Quality (DEQ) said at the Seattle symposium. “So shouldn’t we want to know how recycling is helping us move toward this? We need something better than an abstract recovery rate.”

Research from Allaway’s department has shown, for example, that in certain circumstances, it makes environmental sense to choose packaging such as multi-layered pouches over widely recyclable options like steel cans or plastic jugs because using the hard-to-recycle stuff can do more to reduce overall greenhouse gas emissions, even if they end up in a landfill (see the table below).

However, if a jurisdiction only judges environmental success by whether the recycling rate is increasing, officials would be apt to promote only the recyclable packaging forms, possibly neglecting the results of the broader scientific analysis.

Allaway added that by putting so much stock in diverting as much as possible from the landfill, recycling systems have done more than just failed to look holistically at environmental impacts; they’ve also inadvertently paved the path to low-quality bales.

“If we weren’t so focused on weight-based recovery, contamination never would have been such a problem,” he said. “We wouldn’t be caught up in [China’s] National Sword.”

But while the subtleties and science underpinning SMM thinking have compelled more industry entities to try to bring the concept into their decision-making, the best steps to put such thinking into action on a broader scale are hardly clear. This is especially true when it comes to benchmarking progress and articulating the role of waste diversion programs to residents and government officials.

Seattle is a perfect case study in why pivoting away from weight-based program assessment is easier said than done.

In a presentation at the symposium, SPU’s Bagby outlined the evolution of a municipal recycling program that most industry members would characterize as remarkably successful.

After Seattle closed a pair of landfills in 1987, city planners and economists, including Bagby, carried out waste characterization studies and pondered a number of options that could help the municipality move the needle on trash.

Bagby said the team ultimately determined the most cost-effective scenario would be one in which the city recovered 60 percent of its materials and sent the rest to landfill. After being presented with that analysis, the Seattle City Council chose to adopt a goal of recycling 60 percent of municipal solid waste by 2012.

In the ensuing decades, the city’s waste plan has been regularly updated. For example, in 2004, the city added a life-cycle analysis component to determine how waste diversion actions were having an impact in areas such as global warming and toxicity. Bagby said that with each new report, “we reevaluated everything” and kept cost-effectiveness central in the conversation.

Weight-based recycling rate goals remained an important focus for the city, however.

Seattle’s goal is now to hit 70 percent diversion by 2022. According to Seattle’s most recent recycling rate report, in 2016 the city reached 58.8 percent, a number that includes the single-family, multi-family, self-haul and commercial realms.

The city’s current rate, which is far above the national average of 34.6 percent, is the product of a slew of program additions and outreach efforts that have come on-line over the years. But Bagby believes the goal itself has been an important part of the equation.

“One of the reasons why we picked the recycling goal is we’re trying to reach the public,” she said, adding that growth in the recycling rate is something residents can clearly understand and have supported.

“And recycling rates tend to be immune to the economic cycle,” Bagby noted. “Recovery tons might go down but so will generation. [The metric] needs to be something stable – if there are huge swings, you’ll lose public support.”

Recycling rates, in other words, serve as a straightforward statistical hook that can nab the attention of residents and elected officials. And it’s that engaging element that seems to be lacking as programs try to evolve metrics and account for complexities of the materials stream, such as total carbon emissions associated with a specific type of packaging or the environmental impact of adding truck routes to collect organics.

Cheryl Coleman is the division director of Resource Conservation and Sustainability at the U.S. EPA and has been one of the leaders in transitioning the agency toward an SMM mode of thinking. She acknowledged, though, that it’s a challenge getting other realms of government to fully grasp the SMM concept. She indicated, for instance, she’s had issues communicating the idea to White House officials, both under President Trump and President Obama.

“Eyes glaze over when you’re describing SMM,” she said at the symposium. “I got that from both administrations.”

Nevertheless, a number of stakeholders are trying to find ways to create a harmonious relationship between program measurement and SMM.

Publicly traded Waste Management has developed a project called Spectrum to try to calculate how much bang for their buck municipalities and others can get through different waste diversion considerations.

At the symposium, the company’s senior public affairs director, Susan Robinson, gave the example of a hotel client that was looking for strategies to reduce food waste sent to landfill. Waste Management came back to the company with calculations showing that by focusing only on the “end of the pipe” and setting up an organics collection program with no upstream alterations, greenhouse gas benefits would be low but costs would be high.

Waste Management planners were using a form of SMM thinking, but they were expressing it in black and white financial terms.

“That was enough for them to get it,” noted Robinson, who is also part of an industry partnership called the Sustainable Materials Management Coalition. “They went off and found ways to reduce.”

Robinson and several symposium speakers also suggested that communities could potentially put greater emphasis on their per capita generation rate. That number shows the total waste output for each resident of a jurisdiction, and it could be a good marker of how efforts in product design, policy and consumer choice work together to affect the waste stream.

“A generation goal at least lets you move upstream,” Allaway said.

Allaway noted the Oregon DEQ considered completely eliminating weight-based recovery goals. “Our partners weren’t ready for it,” he said. “That’s OK.”

However, in 2015, Oregon passed Senate Bill 263, which requires DEQ to develop a method of setting recovery rate goals for local jurisdictions in terms of energy savings and allows DEQ to also set goals in terms of other environmental impacts. Such targets would exist in parallel with current weight-based targets.

“Impacts matter more than weight,” said DEQ analyst Martin Brown, “so we are evaluating materials in terms of impacts.”

Brown is behind a DEQ project designed to do that. IMFO (Impacts of Materials Flows in Oregon) is a calculator that aims to let local leaders project the outcomes of diverse materials management strategies.

Brown gave the example of assessing strategies around food waste to find out what the best course of action would be to lower freshwater consumption. A user could use IMFO to determine through data whether it would be more impactful to divert all food waste to compost or to reduce food waste in the first place.

IMFO is a few years away from implementation, Brown and Allaway said. When it does come into use, it will be an alternative to WARM, the U.S. EPA’s own impact calculator. Among other things, IMFO will give users a novel option: estimating the impacts of materials that don’t immediately hit the waste stream.

“For example, the impacts of aluminum include impacts from both soda cans and screen doors, but there aren’t many screen doors in the waste stream,” Brown said. “They get put on houses and stay there. The doors still have production impacts, though, and a true SMM view includes them.”

Impact-based measurements are DEQ’s priority. But for managers who insist on weight-based metrics, Brown suggested replacing recycling rates with what he called “mass circularity.” A mass circularity rate would show the amount of a material recycled divided by the total demand for that material, and the demand number would take into account all uses for a material in a given jurisdiction.

“I acknowledge it’s more work to do this stuff,” said Brown. “But it’s also liberating. When you widen your perspective, you can think of more things you can do to help the world, instead of just increasing recycling.”

The old adage tells us that “you can’t manage what you don’t measure.” That reminder gets particularly interesting, however, when the very thing you are trying to manage is measurement itself.

Recycling rates are built into the DNA of the vast majority of waste programs nationwide. And industry inertia has long pushed recycling professionals to consider recycling rate growth to be the ultimate end game. So for many, the very concept of moving away from weight-based diversion is unsettling.

“Change is hard,” said Susan Fife-Ferris, Seattle’s director of solid waste planning, in closing remarks at the symposium. “You need to be aware that change even needs to happen.”

As the tenets of SMM continue to proliferate, wider-scale shifts will invariably be part of the process. At this point in the game, the industry is in conversation mode, trying to share perspectives and understand the needs of different stakeholders on the measurement front.

Once recycling program managers fully wrap their heads around the issue, then it will be time to more effectively get the wider public thinking in terms of SMM as well.

“Invariably, I hear [SMM] is too complicated,” said Waste Management’s Robinson. “I hear that we can’t talk to public officials about it. But I think we’re on the cusp.”

This story will appear in early 2018 in the print edition of Resource Recycling as part of a package of features on the evolution of sustainable materials management. Make sure you have the earliest possible access to all the analysis delivered by our print edition. Sign up for a trial subscription today.