Does Your Diversion Rate Really Reflect Your Recycling Efforts?

Originally published in Environmental Leader, March 14, 2011

Are you being held hostage by your recycling diversion rate? As more and more companies begin to measure their recycling efforts, this figure is often used as the only performance indicator for recycling. A high diversion rate is seen as an indicator of success, while a low diversion rate assumes an inefficient recycling program.

This reliance on the diversion rate has led to an increasingly skewed understanding of the real impact of recycling programs. By focusing on diversion rates, corporate green teams may be missing the full picture.

Diversion Rate Formula

First, we have to understand how the diversion rate is calculated. The diversion rate or ratio (often used interchangeably with recycling rate/ratio) is calculated as the total recyclables collected over the total waste generated (trash + recyclables), giving you the proportion of a building’s total waste that is recycled.

Depending on a number of factors, diversion rates can vary considerably regardless of actual recycling compliance levels.

Weight Matters

One of the main factors affecting diversion rate is weight. Here’s an example:

Take two buildings of the same size with the same number of floors and the same number of employees. They have the exact same recycling program and compliance levels. But building A has a low diversion rate and building B has a high diversion rate. Why? The only difference is that building A has a cafeteria and building B does not. Because cafeteria waste is heavy, Building A’s waste stream weighs more than Building B’s waste stream. So even though both buildings are recycling the same amount and generating the same amount of waste, building A has a lower diversion rate because it generates heavier waste.

Now if building A wants to improve their diversion rate, they would need to reduce the weight (not amount) of their trash and/or increase the weight (not amount) of their recyclables. This is because waste and recycling information is typically reported in tons, rather than volume.

Here’s another example. Let’s say you have:

– five bags of recyclables: two bags of paper (2 x 20 lbs = 40 lbs) and three bags of plastic bottles (3 x 5 lbs = 15 lbs)

– five bags of trash (5 x 10 lbs = 50 lbs).

Your diversion rate would be 52% (40 + 15 = 55 lbs of recyclables over 105 lbs of total trash and recyclables).

If you replaced one bag of plastic bottles (5 lbs) with one bag of heavier glass bottles (25 lbs), your diversion rate would jump up to 60%. Swap out all three bags of plastic bottles for glass bottles and your diversion rate jumps to 70%. In both cases, you still have five bags of trash and five bags of recyclables. The volume of recyclables has not changed, just the weight, which has increased because of the change in material type, driving up your diversion rate. Now we are not suggesting you switch from plastic to glass but this shows the effect of weight on the diversion rate.

Now let’s say your green team has put in place a paper reduction program so you are generating one bag of paper for recycling each night instead of two, and you continue to generate the same amount of trash (5 bags). Returning to the first example, this means that you now have:

– four bags of recyclables (instead of five): one bag of paper (20 lbs) and three bags of plastic bottles (3 x 5 lbs = 15 lbs)

– five bags of trash (5 x 10 lbs = 50 lbs).

Now your diversion rate will drop from 52% (40 + 15 lbs = 55 lbs of recyclables over 105 lbs of total trash and recyclables) to 41%. (20 lbs + 15 lbs of recyclables over 85 lbs total trash and recyclables).

Your paper reduction program is successful, but it has negatively impacted your diversion rate because you have reduced the amount of recyclables generated. If your sole goal is a higher diversion rate, in this scenario, you may as well tell everyone to go crazy with printing so more paper is generated for recycling!

In short, weight matters. If your waste stream is heavy, you are likely to have a low diversion rate even if you have high recycling compliance levels. If your recyclable stream is heavy, you might have a high diversion rate even if your recycling program isn’t being fully utilized.

Looking Beyond the Diversion Rate

The thing to remember is that the diversion rate is merely an indicator of your building’s recycling performance. It does not give you the full picture. The diversion rate does not tell you how much of your waste stream is recyclable, whether or not you are recycling everything possible, or if you are generating less waste overall.

So don’t be too disappointed if you have a low recycling rate. Instead, figure out why it is low and set realistic goals. Here’s what you can do:

· Perform a waste audit. This will give you a detailed look at what you are throwing out to see what can be moved to the recycling stream.

· Find out if shredded paper is being recycled or thrown away as waste. Often buildings and offices have separate systems dealing with shredded documents and regular paper. Make sure shredded paper is being recycled and included in your recycling data.

· Improve Recycling. Explore ways to reduce waste and increase recycling through efforts like composting. Make sure your tenants and/or employees know about, understand and fully utilize your recycling program.

· Benchmark. Use sustainability metrics to track your waste and recycling so you can set benchmarks and note improvements from year to year. Recording and tracking your waste and recycling data will reveal far more of your recycling story than your diversion rate ever will.

Doing the Right Thing

Finally, having the full picture will help you make right decisions. At a recent waste audit, Great Forest discovered that a client’s waste stream contained a lot of lightweight plastics and Styrofoam. Moving these materials from the waste stream into the recycling stream would not do much to lighten the waste stream, and so would not do much to increase the client’s diversion ratio. Despite this, the client decided to make the effort to move the lightweight plastics and Styrofoam into the recycling stream because they could see the full picture. They realized that their recycling success went beyond the diversion rate to doing the right thing.

And doing the right thing will show stakeholders your commitment to sustainability every time.

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